Merge branch 'master' into feat/text-macro

40 files changed, 2693 insertions, 1317 deletions

diff --git a/widget/Cargo.toml b/widget/Cargo.toml
index 3c9ffddb..3c9f6a54 100644
--- a/widget/Cargo.toml
+++ b/widget/Cargo.toml
@@ -10,6 +10,9 @@ homepage.workspace = true
 categories.workspace = true
 keywords.workspace = true
 
+[lints]
+workspace = true
+
 [package.metadata.docs.rs]
 rustdoc-args = ["--cfg", "docsrs"]
 all-features = true
@@ -21,12 +24,14 @@ svg = ["iced_renderer/svg"]
 canvas = ["iced_renderer/geometry"]
 qr_code = ["canvas", "qrcode"]
 wgpu = ["iced_renderer/wgpu"]
+advanced = []
 
 [dependencies]
 iced_renderer.workspace = true
 iced_runtime.workspace = true
 
 num-traits.workspace = true
+rustc-hash.workspace = true
 thiserror.workspace = true
 unicode-segmentation.workspace = true
 
diff --git a/widget/src/button.rs b/widget/src/button.rs
index 5790f811..dc949671 100644
--- a/widget/src/button.rs
+++ b/widget/src/button.rs
@@ -49,6 +49,7 @@ use crate::core::{
 pub struct Button<'a, Message, Theme = crate::Theme, Renderer = crate::Renderer>
 where
     Renderer: crate::core::Renderer,
+    Theme: Catalog,
 {
     content: Element<'a, Message, Theme, Renderer>,
     on_press: Option<Message>,
@@ -56,20 +57,18 @@ where
     height: Length,
     padding: Padding,
     clip: bool,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Button<'a, Message, Theme, Renderer>
 where
     Renderer: crate::core::Renderer,
+    Theme: Catalog,
 {
     /// Creates a new [`Button`] with the given content.
     pub fn new(
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    ) -> Self {
         let content = content.into();
         let size = content.as_widget().size_hint();
 
@@ -80,7 +79,7 @@ where
             height: size.height.fluid(),
             padding: DEFAULT_PADDING,
             clip: false,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -119,21 +118,30 @@ where
         self
     }
 
-    /// Sets the style variant of this [`Button`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
-        self
-    }
-
     /// Sets whether the contents of the [`Button`] should be clipped on
     /// overflow.
     pub fn clip(mut self, clip: bool) -> Self {
         self.clip = clip;
         self
     }
+
+    /// Sets the style of the [`Button`].
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Button`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
@@ -146,6 +154,7 @@ impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
 where
     Message: 'a + Clone,
     Renderer: 'a + crate::core::Renderer,
+    Theme: Catalog,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<State>()
@@ -304,19 +313,19 @@ where
             Status::Active
         };
 
-        let styling = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
-        if styling.background.is_some()
-            || styling.border.width > 0.0
-            || styling.shadow.color.a > 0.0
+        if style.background.is_some()
+            || style.border.width > 0.0
+            || style.shadow.color.a > 0.0
         {
             renderer.fill_quad(
                 renderer::Quad {
                     bounds,
-                    border: styling.border,
-                    shadow: styling.shadow,
+                    border: style.border,
+                    shadow: style.shadow,
                 },
-                styling
+                style
                     .background
                     .unwrap_or(Background::Color(Color::TRANSPARENT)),
             );
@@ -333,7 +342,7 @@ where
             renderer,
             theme,
             &renderer::Style {
-                text_color: styling.text_color,
+                text_color: style.text_color,
             },
             content_layout,
             cursor,
@@ -378,7 +387,7 @@ impl<'a, Message, Theme, Renderer> From<Button<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: Clone + 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: crate::core::Renderer + 'a,
 {
     fn from(button: Button<'a, Message, Theme, Renderer>) -> Self {
@@ -407,9 +416,9 @@ pub enum Status {
     Disabled,
 }
 
-/// The appearance of a button.
+/// The style of a button.
 #[derive(Debug, Clone, Copy, PartialEq)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the button.
     pub background: Option<Background>,
     /// The text [`Color`] of the button.
@@ -420,8 +429,8 @@ pub struct Appearance {
     pub shadow: Shadow,
 }
 
-impl Appearance {
-    /// Updates the [`Appearance`] with the given [`Background`].
+impl Style {
+    /// Updates the [`Style`] with the given [`Background`].
     pub fn with_background(self, background: impl Into<Background>) -> Self {
         Self {
             background: Some(background.into()),
@@ -430,7 +439,7 @@ impl Appearance {
     }
 }
 
-impl std::default::Default for Appearance {
+impl Default for Style {
     fn default() -> Self {
         Self {
             background: None,
@@ -441,41 +450,41 @@ impl std::default::Default for Appearance {
     }
 }
 
-/// The style of a [`Button`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Button`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Button`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Button`].
-    fn default_style(&self, status: Status) -> Appearance;
-}
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        primary(self, status)
-    }
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+/// A styling function for a [`Button`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(primary)
     }
-}
 
-impl DefaultStyle for Color {
-    fn default_style(&self, _status: Status) -> Appearance {
-        Appearance::default().with_background(*self)
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// A primary button; denoting a main action.
-pub fn primary(theme: &Theme, status: Status) -> Appearance {
+pub fn primary(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
     let base = styled(palette.primary.strong);
 
     match status {
         Status::Active | Status::Pressed => base,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             background: Some(Background::Color(palette.primary.base.color)),
             ..base
         },
@@ -484,13 +493,13 @@ pub fn primary(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A secondary button; denoting a complementary action.
-pub fn secondary(theme: &Theme, status: Status) -> Appearance {
+pub fn secondary(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
     let base = styled(palette.secondary.base);
 
     match status {
         Status::Active | Status::Pressed => base,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             background: Some(Background::Color(palette.secondary.strong.color)),
             ..base
         },
@@ -499,13 +508,13 @@ pub fn secondary(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A success button; denoting a good outcome.
-pub fn success(theme: &Theme, status: Status) -> Appearance {
+pub fn success(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
     let base = styled(palette.success.base);
 
     match status {
         Status::Active | Status::Pressed => base,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             background: Some(Background::Color(palette.success.strong.color)),
             ..base
         },
@@ -514,13 +523,13 @@ pub fn success(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A danger button; denoting a destructive action.
-pub fn danger(theme: &Theme, status: Status) -> Appearance {
+pub fn danger(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
     let base = styled(palette.danger.base);
 
     match status {
         Status::Active | Status::Pressed => base,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             background: Some(Background::Color(palette.danger.strong.color)),
             ..base
         },
@@ -529,17 +538,17 @@ pub fn danger(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A text button; useful for links.
-pub fn text(theme: &Theme, status: Status) -> Appearance {
+pub fn text(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
-    let base = Appearance {
+    let base = Style {
         text_color: palette.background.base.text,
-        ..Appearance::default()
+        ..Style::default()
     };
 
     match status {
         Status::Active | Status::Pressed => base,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             text_color: palette.background.base.text.scale_alpha(0.8),
             ..base
         },
@@ -547,21 +556,21 @@ pub fn text(theme: &Theme, status: Status) -> Appearance {
     }
 }
 
-fn styled(pair: palette::Pair) -> Appearance {
-    Appearance {
+fn styled(pair: palette::Pair) -> Style {
+    Style {
         background: Some(Background::Color(pair.color)),
         text_color: pair.text,
         border: Border::rounded(2),
-        ..Appearance::default()
+        ..Style::default()
     }
 }
 
-fn disabled(appearance: Appearance) -> Appearance {
-    Appearance {
-        background: appearance
+fn disabled(style: Style) -> Style {
+    Style {
+        background: style
             .background
             .map(|background| background.scale_alpha(0.5)),
-        text_color: appearance.text_color.scale_alpha(0.5),
-        ..appearance
+        text_color: style.text_color.scale_alpha(0.5),
+        ..style
     }
 }
diff --git a/widget/src/canvas.rs b/widget/src/canvas.rs
index 0eda0191..be09f163 100644
--- a/widget/src/canvas.rs
+++ b/widget/src/canvas.rs
@@ -6,8 +6,11 @@ mod program;
 pub use event::Event;
 pub use program::Program;
 
-pub use crate::graphics::geometry::*;
-pub use crate::renderer::geometry::*;
+pub use crate::graphics::cache::Group;
+pub use crate::graphics::geometry::{
+    fill, gradient, path, stroke, Fill, Gradient, LineCap, LineDash, LineJoin,
+    Path, Stroke, Style, Text,
+};
 
 use crate::core;
 use crate::core::layout::{self, Layout};
@@ -15,12 +18,25 @@ use crate::core::mouse;
 use crate::core::renderer;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Clipboard, Element, Length, Rectangle, Shell, Size, Transformation, Widget,
+    Clipboard, Element, Length, Rectangle, Shell, Size, Vector, Widget,
 };
 use crate::graphics::geometry;
 
 use std::marker::PhantomData;
 
+/// A simple cache that stores generated [`Geometry`] to avoid recomputation.
+///
+/// A [`Cache`] will not redraw its geometry unless the dimensions of its layer
+/// change or it is explicitly cleared.
+pub type Cache<Renderer = crate::Renderer> = geometry::Cache<Renderer>;
+
+/// The geometry supported by a renderer.
+pub type Geometry<Renderer = crate::Renderer> =
+    <Renderer as geometry::Renderer>::Geometry;
+
+/// The frame supported by a renderer.
+pub type Frame<Renderer = crate::Renderer> = geometry::Frame<Renderer>;
+
 /// A widget capable of drawing 2D graphics.
 ///
 /// ## Drawing a simple circle
@@ -42,7 +58,7 @@ use std::marker::PhantomData;
 /// impl Program<()> for Circle {
 ///     type State = ();
 ///
-///     fn draw(&self, _state: &(), renderer: &Renderer, _theme: &Theme, bounds: Rectangle, _cursor: mouse::Cursor) -> Vec<Geometry>{
+///     fn draw(&self, _state: &(), renderer: &Renderer, _theme: &Theme, bounds: Rectangle, _cursor: mouse::Cursor) -> Vec<Geometry> {
 ///         // We prepare a new `Frame`
 ///         let mut frame = Frame::new(renderer, bounds.size());
 ///
@@ -207,12 +223,15 @@ where
 
         let state = tree.state.downcast_ref::<P::State>();
 
-        renderer.with_transformation(
-            Transformation::translate(bounds.x, bounds.y),
+        renderer.with_translation(
+            Vector::new(bounds.x, bounds.y),
             |renderer| {
-                renderer.draw(
-                    self.program.draw(state, renderer, theme, bounds, cursor),
-                );
+                let layers =
+                    self.program.draw(state, renderer, theme, bounds, cursor);
+
+                for layer in layers {
+                    renderer.draw_geometry(layer);
+                }
             },
         );
     }
diff --git a/widget/src/canvas/program.rs b/widget/src/canvas/program.rs
index 0bff4bda..a7ded0f4 100644
--- a/widget/src/canvas/program.rs
+++ b/widget/src/canvas/program.rs
@@ -1,5 +1,6 @@
 use crate::canvas::event::{self, Event};
 use crate::canvas::mouse;
+use crate::canvas::Geometry;
 use crate::core::Rectangle;
 use crate::graphics::geometry;
 
@@ -52,7 +53,7 @@ where
         theme: &Theme,
         bounds: Rectangle,
         cursor: mouse::Cursor,
-    ) -> Vec<Renderer::Geometry>;
+    ) -> Vec<Geometry<Renderer>>;
 
     /// Returns the current mouse interaction of the [`Program`].
     ///
@@ -94,7 +95,7 @@ where
         theme: &Theme,
         bounds: Rectangle,
         cursor: mouse::Cursor,
-    ) -> Vec<Renderer::Geometry> {
+    ) -> Vec<Geometry<Renderer>> {
         T::draw(self, state, renderer, theme, bounds, cursor)
     }
 
diff --git a/widget/src/checkbox.rs b/widget/src/checkbox.rs
index 15fb8f58..225c316d 100644
--- a/widget/src/checkbox.rs
+++ b/widget/src/checkbox.rs
@@ -39,6 +39,7 @@ pub struct Checkbox<
     Renderer = crate::Renderer,
 > where
     Renderer: text::Renderer,
+    Theme: Catalog,
 {
     is_checked: bool,
     on_toggle: Option<Box<dyn Fn(bool) -> Message + 'a>>,
@@ -51,12 +52,13 @@ pub struct Checkbox<
     text_shaping: text::Shaping,
     font: Option<Renderer::Font>,
     icon: Icon<Renderer::Font>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Checkbox<'a, Message, Theme, Renderer>
 where
     Renderer: text::Renderer,
+    Theme: Catalog,
 {
     /// The default size of a [`Checkbox`].
     const DEFAULT_SIZE: f32 = 16.0;
@@ -69,10 +71,7 @@ where
     /// It expects:
     ///   * the label of the [`Checkbox`]
     ///   * a boolean describing whether the [`Checkbox`] is checked or not
-    pub fn new(label: impl Into<String>, is_checked: bool) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn new(label: impl Into<String>, is_checked: bool) -> Self {
         Checkbox {
             is_checked,
             on_toggle: None,
@@ -91,7 +90,7 @@ where
                 line_height: text::LineHeight::default(),
                 shaping: text::Shaping::Basic,
             },
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -174,11 +173,20 @@ where
     }
 
     /// Sets the style of the [`Checkbox`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Checkbox`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -187,6 +195,7 @@ impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Checkbox<'a, Message, Theme, Renderer>
 where
     Renderer: text::Renderer,
+    Theme: Catalog,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<widget::text::State<Renderer::Paragraph>>()
@@ -285,7 +294,7 @@ where
         tree: &Tree,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         viewport: &Rectangle,
@@ -304,7 +313,7 @@ where
             Status::Active { is_checked }
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
         {
             let layout = children.next().unwrap();
@@ -313,10 +322,10 @@ where
             renderer.fill_quad(
                 renderer::Quad {
                     bounds,
-                    border: appearance.border,
+                    border: style.border,
                     ..renderer::Quad::default()
                 },
-                appearance.background,
+                style.background,
             );
 
             let Icon {
@@ -331,7 +340,7 @@ where
             if self.is_checked {
                 renderer.fill_text(
                     text::Text {
-                        content: &code_point.to_string(),
+                        content: code_point.to_string(),
                         font: *font,
                         size,
                         line_height: *line_height,
@@ -341,7 +350,7 @@ where
                         shaping: *shaping,
                     },
                     bounds.center(),
-                    appearance.icon_color,
+                    style.icon_color,
                     *viewport,
                 );
             }
@@ -352,11 +361,11 @@ where
 
             crate::text::draw(
                 renderer,
-                style,
+                defaults,
                 label_layout,
                 tree.state.downcast_ref(),
-                crate::text::Appearance {
-                    color: appearance.text_color,
+                crate::text::Style {
+                    color: style.text_color,
                 },
                 viewport,
             );
@@ -368,7 +377,7 @@ impl<'a, Message, Theme, Renderer> From<Checkbox<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
+    Theme: 'a + Catalog,
     Renderer: 'a + text::Renderer,
 {
     fn from(
@@ -413,9 +422,9 @@ pub enum Status {
     },
 }
 
-/// The appearance of a checkbox.
+/// The style of a checkbox.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the checkbox.
     pub background: Background,
     /// The icon [`Color`] of the checkbox.
@@ -426,29 +435,37 @@ pub struct Appearance {
     pub text_color: Option<Color>,
 }
 
-/// The style of a [`Checkbox`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Checkbox`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Checkbox`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Checkbox`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        primary(self, status)
+/// A styling function for a [`Checkbox`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(primary)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// A primary checkbox; denoting a main toggle.
-pub fn primary(theme: &Theme, status: Status) -> Appearance {
+pub fn primary(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     match status {
@@ -474,7 +491,7 @@ pub fn primary(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A secondary checkbox; denoting a complementary toggle.
-pub fn secondary(theme: &Theme, status: Status) -> Appearance {
+pub fn secondary(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     match status {
@@ -500,7 +517,7 @@ pub fn secondary(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A success checkbox; denoting a positive toggle.
-pub fn success(theme: &Theme, status: Status) -> Appearance {
+pub fn success(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     match status {
@@ -526,7 +543,7 @@ pub fn success(theme: &Theme, status: Status) -> Appearance {
 }
 
 /// A danger checkbox; denoting a negaive toggle.
-pub fn danger(theme: &Theme, status: Status) -> Appearance {
+pub fn danger(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     match status {
@@ -556,8 +573,8 @@ fn styled(
     base: palette::Pair,
     accent: palette::Pair,
     is_checked: bool,
-) -> Appearance {
-    Appearance {
+) -> Style {
+    Style {
         background: Background::Color(if is_checked {
             accent.color
         } else {
diff --git a/widget/src/column.rs b/widget/src/column.rs
index d37ef695..df7829b3 100644
--- a/widget/src/column.rs
+++ b/widget/src/column.rs
@@ -33,11 +33,18 @@ where
         Self::from_vec(Vec::new())
     }
 
+    /// Creates a [`Column`] with the given capacity.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self::from_vec(Vec::with_capacity(capacity))
+    }
+
     /// Creates a [`Column`] with the given elements.
     pub fn with_children(
         children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
     ) -> Self {
-        Self::new().extend(children)
+        let iterator = children.into_iter();
+
+        Self::with_capacity(iterator.size_hint().0).extend(iterator)
     }
 
     /// Creates a [`Column`] from an already allocated [`Vec`].
diff --git a/widget/src/combo_box.rs b/widget/src/combo_box.rs
index ee24d742..253850df 100644
--- a/widget/src/combo_box.rs
+++ b/widget/src/combo_box.rs
@@ -32,6 +32,7 @@ pub struct ComboBox<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     state: &'a State<T>,
@@ -42,7 +43,7 @@ pub struct ComboBox<
     on_option_hovered: Option<Box<dyn Fn(T) -> Message>>,
     on_close: Option<Message>,
     on_input: Option<Box<dyn Fn(String) -> Message>>,
-    menu_style: menu::Style<'a, Theme>,
+    menu_class: <Theme as menu::Catalog>::Class<'a>,
     padding: Padding,
     size: Option<f32>,
 }
@@ -50,6 +51,7 @@ pub struct ComboBox<
 impl<'a, T, Message, Theme, Renderer> ComboBox<'a, T, Message, Theme, Renderer>
 where
     T: std::fmt::Display + Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// Creates a new [`ComboBox`] with the given list of options, a placeholder,
@@ -60,18 +62,10 @@ where
         placeholder: &str,
         selection: Option<&T>,
         on_selected: impl Fn(T) -> Message + 'static,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
-        let style = Theme::default_style();
-
-        let text_input = TextInput::with_style(
-            placeholder,
-            &state.value(),
-            style.text_input,
-        )
-        .on_input(TextInputEvent::TextChanged);
+    ) -> Self {
+        let text_input = TextInput::new(placeholder, &state.value())
+            .on_input(TextInputEvent::TextChanged)
+            .class(Theme::default_input());
 
         let selection = selection.map(T::to_string).unwrap_or_default();
 
@@ -84,7 +78,7 @@ where
             on_option_hovered: None,
             on_input: None,
             on_close: None,
-            menu_style: style.menu,
+            menu_class: <Theme as Catalog>::default_menu(),
             padding: text_input::DEFAULT_PADDING,
             size: None,
         }
@@ -124,18 +118,6 @@ where
         self
     }
 
-    /// Sets the style of the [`ComboBox`].
-    pub fn style(mut self, style: impl Into<Style<'a, Theme>>) -> Self
-    where
-        Theme: 'a,
-    {
-        let style = style.into();
-
-        self.text_input = self.text_input.style(style.text_input);
-        self.menu_style = style.menu;
-        self
-    }
-
     /// Sets the [`Renderer::Font`] of the [`ComboBox`].
     ///
     /// [`Renderer::Font`]: text::Renderer
@@ -173,6 +155,55 @@ where
             ..self
         }
     }
+
+    /// Sets the style of the input of the [`ComboBox`].
+    #[must_use]
+    pub fn input_style(
+        mut self,
+        style: impl Fn(&Theme, text_input::Status) -> text_input::Style + 'a,
+    ) -> Self
+    where
+        <Theme as text_input::Catalog>::Class<'a>:
+            From<text_input::StyleFn<'a, Theme>>,
+    {
+        self.text_input = self.text_input.style(style);
+        self
+    }
+
+    /// Sets the style of the menu of the [`ComboBox`].
+    #[must_use]
+    pub fn menu_style(
+        mut self,
+        style: impl Fn(&Theme) -> menu::Style + 'a,
+    ) -> Self
+    where
+        <Theme as menu::Catalog>::Class<'a>: From<menu::StyleFn<'a, Theme>>,
+    {
+        self.menu_class = (Box::new(style) as menu::StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the input of the [`ComboBox`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn input_class(
+        mut self,
+        class: impl Into<<Theme as text_input::Catalog>::Class<'a>>,
+    ) -> Self {
+        self.text_input = self.text_input.class(class);
+        self
+    }
+
+    /// Sets the style class of the menu of the [`ComboBox`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn menu_class(
+        mut self,
+        class: impl Into<<Theme as menu::Catalog>::Class<'a>>,
+    ) -> Self {
+        self.menu_class = class.into();
+        self
+    }
 }
 
 /// The local state of a [`ComboBox`].
@@ -296,6 +327,7 @@ impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
 where
     T: Display + Clone + 'static,
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn size(&self) -> Size<Length> {
@@ -668,38 +700,47 @@ where
                 ..
             } = tree.state.downcast_mut::<Menu<T>>();
 
-            let bounds = layout.bounds();
-
             self.state.sync_filtered_options(filtered_options);
 
-            let mut menu = menu::Menu::new(
-                menu,
-                &filtered_options.options,
-                hovered_option,
-                |x| {
-                    tree.children[0]
-                        .state
-                        .downcast_mut::<text_input::State<Renderer::Paragraph>>(
-                        )
-                        .unfocus();
-
-                    (self.on_selected)(x)
-                },
-                self.on_option_hovered.as_deref(),
-                &self.menu_style,
-            )
-            .width(bounds.width)
-            .padding(self.padding);
-
-            if let Some(font) = self.font {
-                menu = menu.font(font);
-            }
+            if filtered_options.options.is_empty() {
+                None
+            } else {
+                let bounds = layout.bounds();
+
+                let mut menu = menu::Menu::new(
+                    menu,
+                    &filtered_options.options,
+                    hovered_option,
+                    |x| {
+                        tree.children[0]
+                    .state
+                    .downcast_mut::<text_input::State<Renderer::Paragraph>>(
+                    )
+                    .unfocus();
+
+                        (self.on_selected)(x)
+                    },
+                    self.on_option_hovered.as_deref(),
+                    &self.menu_class,
+                )
+                .width(bounds.width)
+                .padding(self.padding);
+
+                if let Some(font) = self.font {
+                    menu = menu.font(font);
+                }
 
-            if let Some(size) = self.size {
-                menu = menu.text_size(size);
-            }
+                if let Some(size) = self.size {
+                    menu = menu.text_size(size);
+                }
 
-            Some(menu.overlay(layout.position() + translation, bounds.height))
+                Some(
+                    menu.overlay(
+                        layout.position() + translation,
+                        bounds.height,
+                    ),
+                )
+            }
         } else {
             None
         }
@@ -712,7 +753,7 @@ impl<'a, T, Message, Theme, Renderer>
 where
     T: Display + Clone + 'static,
     Message: Clone + 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(combo_box: ComboBox<'a, T, Message, Theme, Renderer>) -> Self {
@@ -720,6 +761,21 @@ where
     }
 }
 
+/// The theme catalog of a [`ComboBox`].
+pub trait Catalog: text_input::Catalog + menu::Catalog {
+    /// The default class for the text input of the [`ComboBox`].
+    fn default_input<'a>() -> <Self as text_input::Catalog>::Class<'a> {
+        <Self as text_input::Catalog>::default()
+    }
+
+    /// The default class for the menu of the [`ComboBox`].
+    fn default_menu<'a>() -> <Self as menu::Catalog>::Class<'a> {
+        <Self as menu::Catalog>::default()
+    }
+}
+
+impl Catalog for Theme {}
+
 fn search<'a, T, A>(
     options: impl IntoIterator<Item = T> + 'a,
     option_matchers: impl IntoIterator<Item = &'a A> + 'a,
@@ -762,30 +818,3 @@ where
         })
         .collect()
 }
-
-/// The style of a [`ComboBox`].
-#[allow(missing_debug_implementations)]
-pub struct Style<'a, Theme> {
-    /// The style of the [`TextInput`] of the [`ComboBox`].
-    pub text_input: text_input::Style<'a, Theme>,
-
-    /// The style of the [`Menu`] of the [`ComboBox`].
-    ///
-    /// [`Menu`]: menu::Menu
-    pub menu: menu::Style<'a, Theme>,
-}
-
-/// The default style of a [`ComboBox`].
-pub trait DefaultStyle: Sized {
-    /// Returns the default style of a [`ComboBox`].
-    fn default_style() -> Style<'static, Self>;
-}
-
-impl DefaultStyle for Theme {
-    fn default_style() -> Style<'static, Self> {
-        Style {
-            text_input: Box::new(text_input::default),
-            menu: menu::DefaultStyle::default_style(),
-        }
-    }
-}
diff --git a/widget/src/container.rs b/widget/src/container.rs
index 7c133588..51967707 100644
--- a/widget/src/container.rs
+++ b/widget/src/container.rs
@@ -9,8 +9,9 @@ use crate::core::renderer;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::widget::{self, Operation};
 use crate::core::{
-    Background, Border, Clipboard, Color, Element, Layout, Length, Padding,
-    Pixels, Point, Rectangle, Shadow, Shell, Size, Theme, Vector, Widget,
+    self, Background, Border, Clipboard, Color, Element, Layout, Length,
+    Padding, Pixels, Point, Rectangle, Shadow, Shell, Size, Theme, Vector,
+    Widget,
 };
 use crate::runtime::Command;
 
@@ -24,7 +25,8 @@ pub struct Container<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     id: Option<Id>,
     padding: Padding,
@@ -36,27 +38,17 @@ pub struct Container<
     vertical_alignment: alignment::Vertical,
     clip: bool,
     content: Element<'a, Message, Theme, Renderer>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Container<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     /// Creates a [`Container`] with the given content.
     pub fn new(
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
-        Self::with_style(content, Theme::default_style)
-    }
-
-    /// Creates a [`Container`] with the given content and style.
-    pub fn with_style(
-        content: impl Into<Element<'a, Message, Theme, Renderer>>,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
     ) -> Self {
         let content = content.into();
         let size = content.as_widget().size_hint();
@@ -71,7 +63,7 @@ where
             horizontal_alignment: alignment::Horizontal::Left,
             vertical_alignment: alignment::Vertical::Top,
             clip: false,
-            style: Box::new(style),
+            class: Theme::default(),
             content,
         }
     }
@@ -100,6 +92,46 @@ where
         self
     }
 
+    /// Sets the [`Container`] to fill the available space in the horizontal axis.
+    ///
+    /// This can be useful to quickly position content when chained with
+    /// alignment functions—like [`center_x`].
+    ///
+    /// Calling this method is equivalent to calling [`width`] with a
+    /// [`Length::Fill`].
+    ///
+    /// [`center_x`]: Self::center_x
+    /// [`width`]: Self::width
+    pub fn fill_x(self) -> Self {
+        self.width(Length::Fill)
+    }
+
+    /// Sets the [`Container`] to fill the available space in the vetical axis.
+    ///
+    /// This can be useful to quickly position content when chained with
+    /// alignment functions—like [`center_y`].
+    ///
+    /// Calling this method is equivalent to calling [`height`] with a
+    /// [`Length::Fill`].
+    ///
+    /// [`center_y`]: Self::center_x
+    /// [`height`]: Self::height
+    pub fn fill_y(self) -> Self {
+        self.height(Length::Fill)
+    }
+
+    /// Sets the [`Container`] to fill all the available space.
+    ///
+    /// Calling this method is equivalent to chaining [`fill_x`] and
+    /// [`fill_y`].
+    ///
+    /// [`center`]: Self::center
+    /// [`fill_x`]: Self::fill_x
+    /// [`fill_y`]: Self::fill_y
+    pub fn fill(self) -> Self {
+        self.width(Length::Fill).height(Length::Fill)
+    }
+
     /// Sets the maximum width of the [`Container`].
     pub fn max_width(mut self, max_width: impl Into<Pixels>) -> Self {
         self.max_width = max_width.into().0;
@@ -124,25 +156,27 @@ where
         self
     }
 
-    /// Centers the contents in the horizontal axis of the [`Container`].
-    pub fn center_x(mut self) -> Self {
-        self.horizontal_alignment = alignment::Horizontal::Center;
-        self
+    /// Sets the width of the [`Container`] and centers its contents horizontally.
+    pub fn center_x(self, width: impl Into<Length>) -> Self {
+        self.width(width).align_x(alignment::Horizontal::Center)
     }
 
-    /// Centers the contents in the vertical axis of the [`Container`].
-    pub fn center_y(mut self) -> Self {
-        self.vertical_alignment = alignment::Vertical::Center;
-        self
+    /// Sets the height of the [`Container`] and centers its contents vertically.
+    pub fn center_y(self, height: impl Into<Length>) -> Self {
+        self.height(height).align_y(alignment::Vertical::Center)
     }
 
-    /// Sets the style of the [`Container`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
-        self
+    /// Centers the contents in both the horizontal and vertical axes of the
+    /// [`Container`].
+    ///
+    /// This is equivalent to chaining [`center_x`] and [`center_y`].
+    ///
+    /// [`center_x`]: Self::center_x
+    /// [`center_y`]: Self::center_y
+    pub fn center(self, length: impl Into<Length>) -> Self {
+        let length = length.into();
+
+        self.center_x(length).center_y(length)
     }
 
     /// Sets whether the contents of the [`Container`] should be clipped on
@@ -151,12 +185,31 @@ where
         self.clip = clip;
         self
     }
+
+    /// Sets the style of the [`Container`].
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Container`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
 }
 
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Container<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     fn tag(&self) -> tree::Tag {
         self.content.as_widget().tag()
@@ -272,14 +325,7 @@ where
         viewport: &Rectangle,
     ) {
         let bounds = layout.bounds();
-
-        let status = if cursor.is_over(bounds) {
-            Status::Hovered
-        } else {
-            Status::Idle
-        };
-
-        let style = (self.style)(theme, status);
+        let style = theme.style(&self.class);
 
         if let Some(clipped_viewport) = bounds.intersection(viewport) {
             draw_background(renderer, &style, bounds);
@@ -324,8 +370,8 @@ impl<'a, Message, Theme, Renderer> From<Container<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
-    Renderer: 'a + crate::core::Renderer,
+    Theme: Catalog + 'a,
+    Renderer: core::Renderer + 'a,
 {
     fn from(
         column: Container<'a, Message, Theme, Renderer>,
@@ -362,25 +408,25 @@ pub fn layout(
     )
 }
 
-/// Draws the background of a [`Container`] given its [`Appearance`] and its `bounds`.
+/// Draws the background of a [`Container`] given its [`Style`] and its `bounds`.
 pub fn draw_background<Renderer>(
     renderer: &mut Renderer,
-    appearance: &Appearance,
+    style: &Style,
     bounds: Rectangle,
 ) where
-    Renderer: crate::core::Renderer,
+    Renderer: core::Renderer,
 {
-    if appearance.background.is_some()
-        || appearance.border.width > 0.0
-        || appearance.shadow.color.a > 0.0
+    if style.background.is_some()
+        || style.border.width > 0.0
+        || style.shadow.color.a > 0.0
     {
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: appearance.border,
-                shadow: appearance.shadow,
+                border: style.border,
+                shadow: style.shadow,
             },
-            appearance
+            style
                 .background
                 .unwrap_or(Background::Color(Color::TRANSPARENT)),
         );
@@ -502,7 +548,7 @@ pub fn visible_bounds(id: Id) -> Command<Option<Rectangle>> {
 
 /// The appearance of a container.
 #[derive(Debug, Clone, Copy, Default)]
-pub struct Appearance {
+pub struct Style {
     /// The text [`Color`] of the container.
     pub text_color: Option<Color>,
     /// The [`Background`] of the container.
@@ -513,8 +559,8 @@ pub struct Appearance {
     pub shadow: Shadow,
 }
 
-impl Appearance {
-    /// Updates the border of the [`Appearance`] with the given [`Color`] and `width`.
+impl Style {
+    /// Updates the border of the [`Style`] with the given [`Color`] and `width`.
     pub fn with_border(
         self,
         color: impl Into<Color>,
@@ -530,7 +576,7 @@ impl Appearance {
         }
     }
 
-    /// Updates the background of the [`Appearance`].
+    /// Updates the background of the [`Style`].
     pub fn with_background(self, background: impl Into<Background>) -> Self {
         Self {
             background: Some(background.into()),
@@ -539,99 +585,78 @@ impl Appearance {
     }
 }
 
-impl From<Color> for Appearance {
+impl From<Color> for Style {
     fn from(color: Color) -> Self {
         Self::default().with_background(color)
     }
 }
 
-impl From<Gradient> for Appearance {
+impl From<Gradient> for Style {
     fn from(gradient: Gradient) -> Self {
         Self::default().with_background(gradient)
     }
 }
 
-impl From<gradient::Linear> for Appearance {
+impl From<gradient::Linear> for Style {
     fn from(gradient: gradient::Linear) -> Self {
         Self::default().with_background(gradient)
     }
 }
 
-/// The possible status of a [`Container`].
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
-pub enum Status {
-    /// The [`Container`] is idle.
-    Idle,
-    /// The [`Container`] is being hovered.
-    Hovered,
-}
+/// The theme catalog of a [`Container`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The style of a [`Container`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
 
-/// The default style of a [`Container`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Container`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        transparent(self, status)
-    }
-}
+/// A styling function for a [`Container`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
-    }
-}
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
 
-impl DefaultStyle for Color {
-    fn default_style(&self, _status: Status) -> Appearance {
-        Appearance::from(*self)
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(transparent)
     }
-}
-
-impl DefaultStyle for Gradient {
-    fn default_style(&self, _status: Status) -> Appearance {
-        Appearance::from(*self)
-    }
-}
 
-impl DefaultStyle for gradient::Linear {
-    fn default_style(&self, _status: Status) -> Appearance {
-        Appearance::from(*self)
+    fn style(&self, class: &Self::Class<'_>) -> Style {
+        class(self)
     }
 }
 
 /// A transparent [`Container`].
-pub fn transparent<Theme>(_theme: &Theme, _status: Status) -> Appearance {
-    Appearance::default()
+pub fn transparent<Theme>(_theme: &Theme) -> Style {
+    Style::default()
 }
 
 /// A rounded [`Container`] with a background.
-pub fn rounded_box(theme: &Theme, _status: Status) -> Appearance {
+pub fn rounded_box(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
-    Appearance {
+    Style {
         background: Some(palette.background.weak.color.into()),
         border: Border::rounded(2),
-        ..Appearance::default()
+        ..Style::default()
     }
 }
 
 /// A bordered [`Container`] with a background.
-pub fn bordered_box(theme: &Theme, _status: Status) -> Appearance {
+pub fn bordered_box(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
-    Appearance {
+    Style {
         background: Some(palette.background.weak.color.into()),
         border: Border {
             width: 1.0,
             radius: 0.0.into(),
             color: palette.background.strong.color,
         },
-        ..Appearance::default()
+        ..Style::default()
     }
 }
diff --git a/widget/src/helpers.rs b/widget/src/helpers.rs
index b294a1d4..016bafbb 100644
--- a/widget/src/helpers.rs
+++ b/widget/src/helpers.rs
@@ -5,8 +5,9 @@ use crate::combo_box::{self, ComboBox};
 use crate::container::{self, Container};
 use crate::core;
 use crate::core::widget::operation;
-use crate::core::{Element, Length, Pixels};
+use crate::core::{Element, Length, Pixels, Widget};
 use crate::keyed;
+use crate::overlay;
 use crate::pick_list::{self, PickList};
 use crate::progress_bar::{self, ProgressBar};
 use crate::radio::{self, Radio};
@@ -20,7 +21,7 @@ use crate::text_input::{self, TextInput};
 use crate::toggler::{self, Toggler};
 use crate::tooltip::{self, Tooltip};
 use crate::vertical_slider::{self, VerticalSlider};
-use crate::{Column, MouseArea, Row, Space, Themer};
+use crate::{Column, MouseArea, Row, Space, Stack, Themer};
 
 use std::borrow::Borrow;
 use std::ops::RangeInclusive;
@@ -51,6 +52,19 @@ macro_rules! row {
     );
 }
 
+/// Creates a [`Stack`] with the given children.
+///
+/// [`Stack`]: crate::Stack
+#[macro_export]
+macro_rules! stack {
+    () => (
+        $crate::Stack::new()
+    );
+    ($($x:expr),+ $(,)?) => (
+        $crate::Stack::with_children([$($crate::core::Element::from($x)),+])
+    );
+}
+
 /// Creates a new [`Text`] widget with the provided content.
 ///
 /// [`Text`]: core::widget::Text
@@ -104,12 +118,34 @@ pub fn container<'a, Message, Theme, Renderer>(
     content: impl Into<Element<'a, Message, Theme, Renderer>>,
 ) -> Container<'a, Message, Theme, Renderer>
 where
-    Theme: container::DefaultStyle + 'a,
+    Theme: container::Catalog + 'a,
     Renderer: core::Renderer,
 {
     Container::new(content)
 }
 
+/// Creates a new [`Container`] that fills all the available space
+/// and centers its contents inside.
+///
+/// This is equivalent to:
+/// ```rust,no_run
+/// # use iced_widget::core::Length;
+/// # use iced_widget::Container;
+/// # fn container<A>(x: A) -> Container<'static, ()> { unreachable!() }
+/// let centered = container("Centered!").center(Length::Fill);
+/// ```
+///
+/// [`Container`]: crate::Container
+pub fn center<'a, Message, Theme, Renderer>(
+    content: impl Into<Element<'a, Message, Theme, Renderer>>,
+) -> Container<'a, Message, Theme, Renderer>
+where
+    Theme: container::Catalog + 'a,
+    Renderer: core::Renderer,
+{
+    container(content).center(Length::Fill)
+}
+
 /// Creates a new [`Column`] with the given children.
 pub fn column<'a, Message, Theme, Renderer>(
     children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
@@ -143,6 +179,428 @@ where
     Row::with_children(children)
 }
 
+/// Creates a new [`Stack`] with the given children.
+///
+/// [`Stack`]: crate::Stack
+pub fn stack<'a, Message, Theme, Renderer>(
+    children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
+) -> Stack<'a, Message, Theme, Renderer>
+where
+    Renderer: core::Renderer,
+{
+    Stack::with_children(children)
+}
+
+/// Wraps the given widget and captures any mouse button presses inside the bounds of
+/// the widget—effectively making it _opaque_.
+///
+/// This helper is meant to be used to mark elements in a [`Stack`] to avoid mouse
+/// events from passing through layers.
+///
+/// [`Stack`]: crate::Stack
+pub fn opaque<'a, Message, Theme, Renderer>(
+    content: impl Into<Element<'a, Message, Theme, Renderer>>,
+) -> Element<'a, Message, Theme, Renderer>
+where
+    Message: 'a,
+    Theme: 'a,
+    Renderer: core::Renderer + 'a,
+{
+    use crate::core::event::{self, Event};
+    use crate::core::layout::{self, Layout};
+    use crate::core::mouse;
+    use crate::core::renderer;
+    use crate::core::widget::tree::{self, Tree};
+    use crate::core::{Rectangle, Shell, Size};
+
+    struct Opaque<'a, Message, Theme, Renderer> {
+        content: Element<'a, Message, Theme, Renderer>,
+    }
+
+    impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
+        for Opaque<'a, Message, Theme, Renderer>
+    where
+        Renderer: core::Renderer,
+    {
+        fn tag(&self) -> tree::Tag {
+            self.content.as_widget().tag()
+        }
+
+        fn state(&self) -> tree::State {
+            self.content.as_widget().state()
+        }
+
+        fn children(&self) -> Vec<Tree> {
+            self.content.as_widget().children()
+        }
+
+        fn diff(&self, tree: &mut Tree) {
+            self.content.as_widget().diff(tree);
+        }
+
+        fn size(&self) -> Size<Length> {
+            self.content.as_widget().size()
+        }
+
+        fn size_hint(&self) -> Size<Length> {
+            self.content.as_widget().size_hint()
+        }
+
+        fn layout(
+            &self,
+            tree: &mut Tree,
+            renderer: &Renderer,
+            limits: &layout::Limits,
+        ) -> layout::Node {
+            self.content.as_widget().layout(tree, renderer, limits)
+        }
+
+        fn draw(
+            &self,
+            tree: &Tree,
+            renderer: &mut Renderer,
+            theme: &Theme,
+            style: &renderer::Style,
+            layout: Layout<'_>,
+            cursor: mouse::Cursor,
+            viewport: &Rectangle,
+        ) {
+            self.content
+                .as_widget()
+                .draw(tree, renderer, theme, style, layout, cursor, viewport);
+        }
+
+        fn operate(
+            &self,
+            state: &mut Tree,
+            layout: Layout<'_>,
+            renderer: &Renderer,
+            operation: &mut dyn operation::Operation<Message>,
+        ) {
+            self.content
+                .as_widget()
+                .operate(state, layout, renderer, operation);
+        }
+
+        fn on_event(
+            &mut self,
+            state: &mut Tree,
+            event: Event,
+            layout: Layout<'_>,
+            cursor: mouse::Cursor,
+            renderer: &Renderer,
+            clipboard: &mut dyn core::Clipboard,
+            shell: &mut Shell<'_, Message>,
+            viewport: &Rectangle,
+        ) -> event::Status {
+            let is_mouse_press = matches!(
+                event,
+                core::Event::Mouse(mouse::Event::ButtonPressed(_))
+            );
+
+            if let core::event::Status::Captured =
+                self.content.as_widget_mut().on_event(
+                    state, event, layout, cursor, renderer, clipboard, shell,
+                    viewport,
+                )
+            {
+                return event::Status::Captured;
+            }
+
+            if is_mouse_press && cursor.is_over(layout.bounds()) {
+                event::Status::Captured
+            } else {
+                event::Status::Ignored
+            }
+        }
+
+        fn mouse_interaction(
+            &self,
+            state: &core::widget::Tree,
+            layout: core::Layout<'_>,
+            cursor: core::mouse::Cursor,
+            viewport: &core::Rectangle,
+            renderer: &Renderer,
+        ) -> core::mouse::Interaction {
+            let interaction = self
+                .content
+                .as_widget()
+                .mouse_interaction(state, layout, cursor, viewport, renderer);
+
+            if interaction == mouse::Interaction::None
+                && cursor.is_over(layout.bounds())
+            {
+                mouse::Interaction::Idle
+            } else {
+                interaction
+            }
+        }
+
+        fn overlay<'b>(
+            &'b mut self,
+            state: &'b mut core::widget::Tree,
+            layout: core::Layout<'_>,
+            renderer: &Renderer,
+            translation: core::Vector,
+        ) -> Option<core::overlay::Element<'b, Message, Theme, Renderer>>
+        {
+            self.content.as_widget_mut().overlay(
+                state,
+                layout,
+                renderer,
+                translation,
+            )
+        }
+    }
+
+    Element::new(Opaque {
+        content: content.into(),
+    })
+}
+
+/// Displays a widget on top of another one, only when the base widget is hovered.
+///
+/// This works analogously to a [`stack`], but it will only display the layer on top
+/// when the cursor is over the base. It can be useful for removing visual clutter.
+///
+/// [`stack`]: stack()
+pub fn hover<'a, Message, Theme, Renderer>(
+    base: impl Into<Element<'a, Message, Theme, Renderer>>,
+    top: impl Into<Element<'a, Message, Theme, Renderer>>,
+) -> Element<'a, Message, Theme, Renderer>
+where
+    Message: 'a,
+    Theme: 'a,
+    Renderer: core::Renderer + 'a,
+{
+    use crate::core::event::{self, Event};
+    use crate::core::layout::{self, Layout};
+    use crate::core::mouse;
+    use crate::core::renderer;
+    use crate::core::widget::tree::{self, Tree};
+    use crate::core::{Rectangle, Shell, Size};
+
+    struct Hover<'a, Message, Theme, Renderer> {
+        base: Element<'a, Message, Theme, Renderer>,
+        top: Element<'a, Message, Theme, Renderer>,
+        is_top_overlay_active: bool,
+    }
+
+    impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
+        for Hover<'a, Message, Theme, Renderer>
+    where
+        Renderer: core::Renderer,
+    {
+        fn tag(&self) -> tree::Tag {
+            struct Tag;
+            tree::Tag::of::<Tag>()
+        }
+
+        fn children(&self) -> Vec<Tree> {
+            vec![Tree::new(&self.base), Tree::new(&self.top)]
+        }
+
+        fn diff(&self, tree: &mut Tree) {
+            tree.diff_children(&[&self.base, &self.top]);
+        }
+
+        fn size(&self) -> Size<Length> {
+            self.base.as_widget().size()
+        }
+
+        fn size_hint(&self) -> Size<Length> {
+            self.base.as_widget().size_hint()
+        }
+
+        fn layout(
+            &self,
+            tree: &mut Tree,
+            renderer: &Renderer,
+            limits: &layout::Limits,
+        ) -> layout::Node {
+            let base = self.base.as_widget().layout(
+                &mut tree.children[0],
+                renderer,
+                limits,
+            );
+
+            let top = self.top.as_widget().layout(
+                &mut tree.children[1],
+                renderer,
+                &layout::Limits::new(Size::ZERO, base.size()),
+            );
+
+            layout::Node::with_children(base.size(), vec![base, top])
+        }
+
+        fn draw(
+            &self,
+            tree: &Tree,
+            renderer: &mut Renderer,
+            theme: &Theme,
+            style: &renderer::Style,
+            layout: Layout<'_>,
+            cursor: mouse::Cursor,
+            viewport: &Rectangle,
+        ) {
+            if let Some(bounds) = layout.bounds().intersection(viewport) {
+                let mut children = layout.children().zip(&tree.children);
+
+                let (base_layout, base_tree) = children.next().unwrap();
+
+                self.base.as_widget().draw(
+                    base_tree,
+                    renderer,
+                    theme,
+                    style,
+                    base_layout,
+                    cursor,
+                    viewport,
+                );
+
+                if cursor.is_over(layout.bounds()) || self.is_top_overlay_active
+                {
+                    let (top_layout, top_tree) = children.next().unwrap();
+
+                    renderer.with_layer(bounds, |renderer| {
+                        self.top.as_widget().draw(
+                            top_tree, renderer, theme, style, top_layout,
+                            cursor, viewport,
+                        );
+                    });
+                }
+            }
+        }
+
+        fn operate(
+            &self,
+            tree: &mut Tree,
+            layout: Layout<'_>,
+            renderer: &Renderer,
+            operation: &mut dyn operation::Operation<Message>,
+        ) {
+            let children = [&self.base, &self.top]
+                .into_iter()
+                .zip(layout.children().zip(&mut tree.children));
+
+            for (child, (layout, tree)) in children {
+                child.as_widget().operate(tree, layout, renderer, operation);
+            }
+        }
+
+        fn on_event(
+            &mut self,
+            tree: &mut Tree,
+            event: Event,
+            layout: Layout<'_>,
+            cursor: mouse::Cursor,
+            renderer: &Renderer,
+            clipboard: &mut dyn core::Clipboard,
+            shell: &mut Shell<'_, Message>,
+            viewport: &Rectangle,
+        ) -> event::Status {
+            let mut children = layout.children().zip(&mut tree.children);
+            let (base_layout, base_tree) = children.next().unwrap();
+
+            let top_status = if matches!(
+                event,
+                Event::Mouse(
+                    mouse::Event::CursorMoved { .. }
+                        | mouse::Event::ButtonReleased(_)
+                )
+            ) || cursor.is_over(layout.bounds())
+            {
+                let (top_layout, top_tree) = children.next().unwrap();
+
+                self.top.as_widget_mut().on_event(
+                    top_tree,
+                    event.clone(),
+                    top_layout,
+                    cursor,
+                    renderer,
+                    clipboard,
+                    shell,
+                    viewport,
+                )
+            } else {
+                event::Status::Ignored
+            };
+
+            if top_status == event::Status::Captured {
+                return top_status;
+            }
+
+            self.base.as_widget_mut().on_event(
+                base_tree,
+                event.clone(),
+                base_layout,
+                cursor,
+                renderer,
+                clipboard,
+                shell,
+                viewport,
+            )
+        }
+
+        fn mouse_interaction(
+            &self,
+            tree: &Tree,
+            layout: Layout<'_>,
+            cursor: mouse::Cursor,
+            viewport: &Rectangle,
+            renderer: &Renderer,
+        ) -> mouse::Interaction {
+            [&self.base, &self.top]
+                .into_iter()
+                .rev()
+                .zip(layout.children().rev().zip(tree.children.iter().rev()))
+                .map(|(child, (layout, tree))| {
+                    child.as_widget().mouse_interaction(
+                        tree, layout, cursor, viewport, renderer,
+                    )
+                })
+                .find(|&interaction| interaction != mouse::Interaction::None)
+                .unwrap_or_default()
+        }
+
+        fn overlay<'b>(
+            &'b mut self,
+            tree: &'b mut core::widget::Tree,
+            layout: core::Layout<'_>,
+            renderer: &Renderer,
+            translation: core::Vector,
+        ) -> Option<core::overlay::Element<'b, Message, Theme, Renderer>>
+        {
+            let mut overlays = [&mut self.base, &mut self.top]
+                .into_iter()
+                .zip(layout.children().zip(tree.children.iter_mut()))
+                .map(|(child, (layout, tree))| {
+                    child.as_widget_mut().overlay(
+                        tree,
+                        layout,
+                        renderer,
+                        translation,
+                    )
+                });
+
+            if let Some(base_overlay) = overlays.next()? {
+                return Some(base_overlay);
+            }
+
+            let top_overlay = overlays.next()?;
+            self.is_top_overlay_active = top_overlay.is_some();
+
+            top_overlay
+        }
+    }
+
+    Element::new(Hover {
+        base: base.into(),
+        top: top.into(),
+        is_top_overlay_active: false,
+    })
+}
+
 /// Creates a new [`Scrollable`] with the provided content.
 ///
 /// [`Scrollable`]: crate::Scrollable
@@ -150,7 +608,7 @@ pub fn scrollable<'a, Message, Theme, Renderer>(
     content: impl Into<Element<'a, Message, Theme, Renderer>>,
 ) -> Scrollable<'a, Message, Theme, Renderer>
 where
-    Theme: scrollable::DefaultStyle + 'a,
+    Theme: scrollable::Catalog + 'a,
     Renderer: core::Renderer,
 {
     Scrollable::new(content)
@@ -163,7 +621,7 @@ pub fn button<'a, Message, Theme, Renderer>(
     content: impl Into<Element<'a, Message, Theme, Renderer>>,
 ) -> Button<'a, Message, Theme, Renderer>
 where
-    Theme: button::DefaultStyle + 'a,
+    Theme: button::Catalog + 'a,
     Renderer: core::Renderer,
 {
     Button::new(content)
@@ -180,7 +638,7 @@ pub fn tooltip<'a, Message, Theme, Renderer>(
     position: tooltip::Position,
 ) -> crate::Tooltip<'a, Message, Theme, Renderer>
 where
-    Theme: container::DefaultStyle + 'a,
+    Theme: container::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     Tooltip::new(content, tooltip, position)
@@ -190,13 +648,26 @@ where
 ///
 /// [`Text`]: core::widget::Text
 pub fn text<'a, Theme, Renderer>(
-    text: impl ToString,
+    text: impl text::IntoFragment<'a>,
+) -> Text<'a, Theme, Renderer>
+where
+    Theme: text::Catalog + 'a,
+    Renderer: core::text::Renderer,
+{
+    Text::new(text)
+}
+
+/// Creates a new [`Text`] widget that displays the provided value.
+///
+/// [`Text`]: core::widget::Text
+pub fn value<'a, Theme, Renderer>(
+    value: impl ToString,
 ) -> Text<'a, Theme, Renderer>
 where
-    Theme: text::DefaultStyle + 'a,
+    Theme: text::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
-    Text::new(text.to_string())
+    Text::new(value.to_string())
 }
 
 /// Creates a new [`Checkbox`].
@@ -207,7 +678,7 @@ pub fn checkbox<'a, Message, Theme, Renderer>(
     is_checked: bool,
 ) -> Checkbox<'a, Message, Theme, Renderer>
 where
-    Theme: checkbox::DefaultStyle + 'a,
+    Theme: checkbox::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     Checkbox::new(label, is_checked)
@@ -224,7 +695,7 @@ pub fn radio<'a, Message, Theme, Renderer, V>(
 ) -> Radio<'a, Message, Theme, Renderer>
 where
     Message: Clone,
-    Theme: radio::DefaultStyle + 'a,
+    Theme: radio::Catalog + 'a,
     Renderer: core::text::Renderer,
     V: Copy + Eq,
 {
@@ -240,7 +711,7 @@ pub fn toggler<'a, Message, Theme, Renderer>(
     f: impl Fn(bool) -> Message + 'a,
 ) -> Toggler<'a, Message, Theme, Renderer>
 where
-    Theme: toggler::DefaultStyle + 'a,
+    Theme: toggler::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     Toggler::new(label, is_checked, f)
@@ -255,7 +726,7 @@ pub fn text_input<'a, Message, Theme, Renderer>(
 ) -> TextInput<'a, Message, Theme, Renderer>
 where
     Message: Clone,
-    Theme: text_input::DefaultStyle + 'a,
+    Theme: text_input::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     TextInput::new(placeholder, value)
@@ -269,7 +740,7 @@ pub fn text_editor<'a, Message, Theme, Renderer>(
 ) -> TextEditor<'a, core::text::highlighter::PlainText, Message, Theme, Renderer>
 where
     Message: Clone,
-    Theme: text_editor::DefaultStyle + 'a,
+    Theme: text_editor::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     TextEditor::new(content)
@@ -286,7 +757,7 @@ pub fn slider<'a, T, Message, Theme>(
 where
     T: Copy + From<u8> + std::cmp::PartialOrd,
     Message: Clone,
-    Theme: slider::DefaultStyle + 'a,
+    Theme: slider::Catalog + 'a,
 {
     Slider::new(range, value, on_change)
 }
@@ -302,7 +773,7 @@ pub fn vertical_slider<'a, T, Message, Theme>(
 where
     T: Copy + From<u8> + std::cmp::PartialOrd,
     Message: Clone,
-    Theme: vertical_slider::DefaultStyle + 'a,
+    Theme: vertical_slider::Catalog + 'a,
 {
     VerticalSlider::new(range, value, on_change)
 }
@@ -320,7 +791,7 @@ where
     L: Borrow<[T]> + 'a,
     V: Borrow<T> + 'a,
     Message: Clone,
-    Theme: pick_list::DefaultStyle,
+    Theme: pick_list::Catalog + overlay::menu::Catalog,
     Renderer: core::text::Renderer,
 {
     PickList::new(options, selected, on_selected)
@@ -337,7 +808,7 @@ pub fn combo_box<'a, T, Message, Theme, Renderer>(
 ) -> ComboBox<'a, T, Message, Theme, Renderer>
 where
     T: std::fmt::Display + Clone,
-    Theme: combo_box::DefaultStyle + 'a,
+    Theme: combo_box::Catalog + 'a,
     Renderer: core::text::Renderer,
 {
     ComboBox::new(state, placeholder, selection, on_selected)
@@ -364,7 +835,7 @@ pub fn vertical_space() -> Space {
 /// [`Rule`]: crate::Rule
 pub fn horizontal_rule<'a, Theme>(height: impl Into<Pixels>) -> Rule<'a, Theme>
 where
-    Theme: rule::DefaultStyle + 'a,
+    Theme: rule::Catalog + 'a,
 {
     Rule::horizontal(height)
 }
@@ -374,7 +845,7 @@ where
 /// [`Rule`]: crate::Rule
 pub fn vertical_rule<'a, Theme>(width: impl Into<Pixels>) -> Rule<'a, Theme>
 where
-    Theme: rule::DefaultStyle + 'a,
+    Theme: rule::Catalog + 'a,
 {
     Rule::vertical(width)
 }
@@ -391,7 +862,7 @@ pub fn progress_bar<'a, Theme>(
     value: f32,
 ) -> ProgressBar<'a, Theme>
 where
-    Theme: progress_bar::DefaultStyle + 'a,
+    Theme: progress_bar::Catalog + 'a,
 {
     ProgressBar::new(range, value)
 }
@@ -413,7 +884,7 @@ pub fn svg<'a, Theme>(
     handle: impl Into<core::svg::Handle>,
 ) -> crate::Svg<'a, Theme>
 where
-    Theme: crate::svg::DefaultStyle + 'a,
+    Theme: crate::svg::Catalog,
 {
     crate::Svg::new(handle)
 }
@@ -441,7 +912,7 @@ pub fn qr_code<'a, Theme>(
     data: &'a crate::qr_code::Data,
 ) -> crate::QRCode<'a, Theme>
 where
-    Theme: crate::qr_code::DefaultStyle + 'a,
+    Theme: crate::qr_code::Catalog + 'a,
 {
     crate::QRCode::new(data)
 }
diff --git a/widget/src/image.rs b/widget/src/image.rs
index ccf1f175..80e17263 100644
--- a/widget/src/image.rs
+++ b/widget/src/image.rs
@@ -8,11 +8,10 @@ use crate::core::mouse;
 use crate::core::renderer;
 use crate::core::widget::Tree;
 use crate::core::{
-    ContentFit, Element, Layout, Length, Rectangle, Size, Vector, Widget,
+    ContentFit, Element, Layout, Length, Point, Rectangle, Rotation, Size,
+    Vector, Widget,
 };
 
-use std::hash::Hash;
-
 pub use image::{FilterMethod, Handle};
 
 /// Creates a new [`Viewer`] with the given image `Handle`.
@@ -38,6 +37,8 @@ pub struct Image<Handle> {
     height: Length,
     content_fit: ContentFit,
     filter_method: FilterMethod,
+    rotation: Rotation,
+    opacity: f32,
 }
 
 impl<Handle> Image<Handle> {
@@ -47,8 +48,10 @@ impl<Handle> Image<Handle> {
             handle: handle.into(),
             width: Length::Shrink,
             height: Length::Shrink,
-            content_fit: ContentFit::Contain,
+            content_fit: ContentFit::default(),
             filter_method: FilterMethod::default(),
+            rotation: Rotation::default(),
+            opacity: 1.0,
         }
     }
 
@@ -77,6 +80,21 @@ impl<Handle> Image<Handle> {
         self.filter_method = filter_method;
         self
     }
+
+    /// Applies the given [`Rotation`] to the [`Image`].
+    pub fn rotation(mut self, rotation: impl Into<Rotation>) -> Self {
+        self.rotation = rotation.into();
+        self
+    }
+
+    /// Sets the opacity of the [`Image`].
+    ///
+    /// It should be in the [0.0, 1.0] range—`0.0` meaning completely transparent,
+    /// and `1.0` meaning completely opaque.
+    pub fn opacity(mut self, opacity: impl Into<f32>) -> Self {
+        self.opacity = opacity.into();
+        self
+    }
 }
 
 /// Computes the layout of an [`Image`].
@@ -87,22 +105,24 @@ pub fn layout<Renderer, Handle>(
     width: Length,
     height: Length,
     content_fit: ContentFit,
+    rotation: Rotation,
 ) -> layout::Node
 where
     Renderer: image::Renderer<Handle = Handle>,
 {
     // The raw w/h of the underlying image
-    let image_size = {
-        let Size { width, height } = renderer.dimensions(handle);
+    let image_size = renderer.measure_image(handle);
+    let image_size =
+        Size::new(image_size.width as f32, image_size.height as f32);
 
-        Size::new(width as f32, height as f32)
-    };
+    // The rotated size of the image
+    let rotated_size = rotation.apply(image_size);
 
     // The size to be available to the widget prior to `Shrink`ing
-    let raw_size = limits.resolve(width, height, image_size);
+    let raw_size = limits.resolve(width, height, rotated_size);
 
     // The uncropped size of the image when fit to the bounds above
-    let full_size = content_fit.fit(image_size, raw_size);
+    let full_size = content_fit.fit(rotated_size, raw_size);
 
     // Shrink the widget to fit the resized image, if requested
     let final_size = Size {
@@ -126,29 +146,47 @@ pub fn draw<Renderer, Handle>(
     handle: &Handle,
     content_fit: ContentFit,
     filter_method: FilterMethod,
+    rotation: Rotation,
+    opacity: f32,
 ) where
     Renderer: image::Renderer<Handle = Handle>,
-    Handle: Clone + Hash,
+    Handle: Clone,
 {
-    let Size { width, height } = renderer.dimensions(handle);
+    let Size { width, height } = renderer.measure_image(handle);
     let image_size = Size::new(width as f32, height as f32);
+    let rotated_size = rotation.apply(image_size);
 
     let bounds = layout.bounds();
-    let adjusted_fit = content_fit.fit(image_size, bounds.size());
+    let adjusted_fit = content_fit.fit(rotated_size, bounds.size());
 
-    let render = |renderer: &mut Renderer| {
-        let offset = Vector::new(
-            (bounds.width - adjusted_fit.width).max(0.0) / 2.0,
-            (bounds.height - adjusted_fit.height).max(0.0) / 2.0,
-        );
+    let scale = Vector::new(
+        adjusted_fit.width / rotated_size.width,
+        adjusted_fit.height / rotated_size.height,
+    );
+
+    let final_size = image_size * scale;
 
-        let drawing_bounds = Rectangle {
-            width: adjusted_fit.width,
-            height: adjusted_fit.height,
-            ..bounds
-        };
+    let position = match content_fit {
+        ContentFit::None => Point::new(
+            bounds.x + (rotated_size.width - adjusted_fit.width) / 2.0,
+            bounds.y + (rotated_size.height - adjusted_fit.height) / 2.0,
+        ),
+        _ => Point::new(
+            bounds.center_x() - final_size.width / 2.0,
+            bounds.center_y() - final_size.height / 2.0,
+        ),
+    };
+
+    let drawing_bounds = Rectangle::new(position, final_size);
 
-        renderer.draw(handle.clone(), filter_method, drawing_bounds + offset);
+    let render = |renderer: &mut Renderer| {
+        renderer.draw_image(
+            handle.clone(),
+            filter_method,
+            drawing_bounds,
+            rotation.radians(),
+            opacity,
+        );
     };
 
     if adjusted_fit.width > bounds.width || adjusted_fit.height > bounds.height
@@ -163,7 +201,7 @@ impl<Message, Theme, Renderer, Handle> Widget<Message, Theme, Renderer>
     for Image<Handle>
 where
     Renderer: image::Renderer<Handle = Handle>,
-    Handle: Clone + Hash,
+    Handle: Clone,
 {
     fn size(&self) -> Size<Length> {
         Size {
@@ -185,6 +223,7 @@ where
             self.width,
             self.height,
             self.content_fit,
+            self.rotation,
         )
     }
 
@@ -204,6 +243,8 @@ where
             &self.handle,
             self.content_fit,
             self.filter_method,
+            self.rotation,
+            self.opacity,
         );
     }
 }
@@ -212,7 +253,7 @@ impl<'a, Message, Theme, Renderer, Handle> From<Image<Handle>>
     for Element<'a, Message, Theme, Renderer>
 where
     Renderer: image::Renderer<Handle = Handle>,
-    Handle: Clone + Hash + 'a,
+    Handle: Clone + 'a,
 {
     fn from(image: Image<Handle>) -> Element<'a, Message, Theme, Renderer> {
         Element::new(image)
diff --git a/widget/src/image/viewer.rs b/widget/src/image/viewer.rs
index 2e3fd713..8fe6f021 100644
--- a/widget/src/image/viewer.rs
+++ b/widget/src/image/viewer.rs
@@ -6,12 +6,10 @@ use crate::core::mouse;
 use crate::core::renderer;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Clipboard, Element, Layout, Length, Pixels, Point, Rectangle, Shell, Size,
-    Vector, Widget,
+    Clipboard, Element, Layout, Length, Pixels, Point, Radians, Rectangle,
+    Shell, Size, Vector, Widget,
 };
 
-use std::hash::Hash;
-
 /// A frame that displays an image with the ability to zoom in/out and pan.
 #[allow(missing_debug_implementations)]
 pub struct Viewer<Handle> {
@@ -94,7 +92,7 @@ impl<Message, Theme, Renderer, Handle> Widget<Message, Theme, Renderer>
     for Viewer<Handle>
 where
     Renderer: image::Renderer<Handle = Handle>,
-    Handle: Clone + Hash,
+    Handle: Clone,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<State>()
@@ -117,7 +115,7 @@ where
         renderer: &Renderer,
         limits: &layout::Limits,
     ) -> layout::Node {
-        let Size { width, height } = renderer.dimensions(&self.handle);
+        let Size { width, height } = renderer.measure_image(&self.handle);
 
         let mut size = limits.resolve(
             self.width,
@@ -218,7 +216,7 @@ where
                 event::Status::Captured
             }
             Event::Mouse(mouse::Event::ButtonPressed(mouse::Button::Left)) => {
-                let Some(cursor_position) = cursor.position() else {
+                let Some(cursor_position) = cursor.position_over(bounds) else {
                     return event::Status::Ignored;
                 };
 
@@ -304,7 +302,7 @@ where
         } else if is_mouse_over {
             mouse::Interaction::Grab
         } else {
-            mouse::Interaction::Idle
+            mouse::Interaction::None
         }
     }
 
@@ -335,8 +333,7 @@ where
 
         renderer.with_layer(bounds, |renderer| {
             renderer.with_translation(translation, |renderer| {
-                image::Renderer::draw(
-                    renderer,
+                renderer.draw_image(
                     self.handle.clone(),
                     self.filter_method,
                     Rectangle {
@@ -344,6 +341,8 @@ where
                         y: bounds.y,
                         ..Rectangle::with_size(image_size)
                     },
+                    Radians(0.0),
+                    1.0,
                 );
             });
         });
@@ -402,7 +401,7 @@ impl<'a, Message, Theme, Renderer, Handle> From<Viewer<Handle>>
 where
     Renderer: 'a + image::Renderer<Handle = Handle>,
     Message: 'a,
-    Handle: Clone + Hash + 'a,
+    Handle: Clone + 'a,
 {
     fn from(viewer: Viewer<Handle>) -> Element<'a, Message, Theme, Renderer> {
         Element::new(viewer)
@@ -421,7 +420,7 @@ pub fn image_size<Renderer>(
 where
     Renderer: image::Renderer,
 {
-    let Size { width, height } = renderer.dimensions(handle);
+    let Size { width, height } = renderer.measure_image(handle);
 
     let (width, height) = {
         let dimensions = (width as f32, height as f32);
diff --git a/widget/src/keyed/column.rs b/widget/src/keyed/column.rs
index 8a8d5fe7..fdaadefa 100644
--- a/widget/src/keyed/column.rs
+++ b/widget/src/keyed/column.rs
@@ -40,27 +40,49 @@ where
 {
     /// Creates an empty [`Column`].
     pub fn new() -> Self {
-        Column {
+        Self::from_vecs(Vec::new(), Vec::new())
+    }
+
+    /// Creates a [`Column`] from already allocated [`Vec`]s.
+    ///
+    /// Keep in mind that the [`Column`] will not inspect the [`Vec`]s, which means
+    /// it won't automatically adapt to the sizing strategy of its contents.
+    ///
+    /// If any of the children have a [`Length::Fill`] strategy, you will need to
+    /// call [`Column::width`] or [`Column::height`] accordingly.
+    pub fn from_vecs(
+        keys: Vec<Key>,
+        children: Vec<Element<'a, Message, Theme, Renderer>>,
+    ) -> Self {
+        Self {
             spacing: 0.0,
             padding: Padding::ZERO,
             width: Length::Shrink,
             height: Length::Shrink,
             max_width: f32::INFINITY,
             align_items: Alignment::Start,
-            keys: Vec::new(),
-            children: Vec::new(),
+            keys,
+            children,
         }
     }
 
+    /// Creates a [`Column`] with the given capacity.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self::from_vecs(
+            Vec::with_capacity(capacity),
+            Vec::with_capacity(capacity),
+        )
+    }
+
     /// Creates a [`Column`] with the given elements.
     pub fn with_children(
         children: impl IntoIterator<
             Item = (Key, Element<'a, Message, Theme, Renderer>),
         >,
     ) -> Self {
-        children
-            .into_iter()
-            .fold(Self::new(), |column, (key, child)| column.push(key, child))
+        let iterator = children.into_iter();
+
+        Self::with_capacity(iterator.size_hint().0).extend(iterator)
     }
 
     /// Sets the vertical spacing _between_ elements.
@@ -132,6 +154,18 @@ where
             self
         }
     }
+
+    /// Extends the [`Column`] with the given children.
+    pub fn extend(
+        self,
+        children: impl IntoIterator<
+            Item = (Key, Element<'a, Message, Theme, Renderer>),
+        >,
+    ) -> Self {
+        children
+            .into_iter()
+            .fold(self, |column, (key, child)| column.push(key, child))
+    }
 }
 
 impl<'a, Key, Message, Renderer> Default for Column<'a, Key, Message, Renderer>
@@ -190,7 +224,7 @@ where
         );
 
         if state.keys != self.keys {
-            state.keys = self.keys.clone();
+            state.keys.clone_from(&self.keys);
         }
     }
 
diff --git a/widget/src/lazy.rs b/widget/src/lazy.rs
index eb663ea5..04783dbe 100644
--- a/widget/src/lazy.rs
+++ b/widget/src/lazy.rs
@@ -18,11 +18,12 @@ use crate::core::widget::tree::{self, Tree};
 use crate::core::widget::{self, Widget};
 use crate::core::Element;
 use crate::core::{
-    self, Clipboard, Hasher, Length, Point, Rectangle, Shell, Size, Vector,
+    self, Clipboard, Length, Point, Rectangle, Shell, Size, Vector,
 };
 use crate::runtime::overlay::Nested;
 
 use ouroboros::self_referencing;
+use rustc_hash::FxHasher;
 use std::cell::RefCell;
 use std::hash::{Hash, Hasher as H};
 use std::rc::Rc;
@@ -106,9 +107,12 @@ where
     }
 
     fn state(&self) -> tree::State {
-        let mut hasher = Hasher::default();
-        self.dependency.hash(&mut hasher);
-        let hash = hasher.finish();
+        let hash = {
+            let mut hasher = FxHasher::default();
+            self.dependency.hash(&mut hasher);
+
+            hasher.finish()
+        };
 
         let element =
             Rc::new(RefCell::new(Some((self.view)(&self.dependency).into())));
@@ -127,9 +131,12 @@ where
             .state
             .downcast_mut::<Internal<Message, Theme, Renderer>>();
 
-        let mut hasher = Hasher::default();
-        self.dependency.hash(&mut hasher);
-        let new_hash = hasher.finish();
+        let new_hash = {
+            let mut hasher = FxHasher::default();
+            self.dependency.hash(&mut hasher);
+
+            hasher.finish()
+        };
 
         if current.hash != new_hash {
             current.hash = new_hash;
diff --git a/widget/src/lazy/component.rs b/widget/src/lazy/component.rs
index a512e0de..7ba71a02 100644
--- a/widget/src/lazy/component.rs
+++ b/widget/src/lazy/component.rs
@@ -478,12 +478,14 @@ where
         translation: Vector,
     ) -> Option<overlay::Element<'b, Message, Theme, Renderer>> {
         self.rebuild_element_if_necessary();
+
         let tree = tree
             .state
             .downcast_mut::<Rc<RefCell<Option<Tree>>>>()
             .borrow_mut()
             .take()
             .unwrap();
+
         let overlay = Overlay(Some(
             InnerBuilder {
                 instance: self,
diff --git a/widget/src/lazy/responsive.rs b/widget/src/lazy/responsive.rs
index 313e1edb..f612102e 100644
--- a/widget/src/lazy/responsive.rs
+++ b/widget/src/lazy/responsive.rs
@@ -308,10 +308,13 @@ where
                     content_layout_node.as_ref().unwrap(),
                 );
 
-                element
-                    .as_widget_mut()
-                    .overlay(tree, content_layout, renderer, translation)
-                    .map(|overlay| RefCell::new(Nested::new(overlay)))
+                (
+                    element
+                        .as_widget_mut()
+                        .overlay(tree, content_layout, renderer, translation)
+                        .map(|overlay| RefCell::new(Nested::new(overlay))),
+                    content_layout_node,
+                )
             },
         }
         .build();
@@ -341,7 +344,10 @@ struct Overlay<'a, 'b, Message, Theme, Renderer> {
 
     #[borrows(mut content, mut tree)]
     #[not_covariant]
-    overlay: Option<RefCell<Nested<'this, Message, Theme, Renderer>>>,
+    overlay: (
+        Option<RefCell<Nested<'this, Message, Theme, Renderer>>>,
+        &'this mut Option<layout::Node>,
+    ),
 }
 
 impl<'a, 'b, Message, Theme, Renderer>
@@ -351,7 +357,7 @@ impl<'a, 'b, Message, Theme, Renderer>
         &self,
         f: impl FnOnce(&mut Nested<'_, Message, Theme, Renderer>) -> T,
     ) -> Option<T> {
-        self.with_overlay(|overlay| {
+        self.with_overlay(|(overlay, _layout)| {
             overlay.as_ref().map(|nested| (f)(&mut nested.borrow_mut()))
         })
     }
@@ -360,7 +366,7 @@ impl<'a, 'b, Message, Theme, Renderer>
         &mut self,
         f: impl FnOnce(&mut Nested<'_, Message, Theme, Renderer>) -> T,
     ) -> Option<T> {
-        self.with_overlay_mut(|overlay| {
+        self.with_overlay_mut(|(overlay, _layout)| {
             overlay.as_mut().map(|nested| (f)(nested.get_mut()))
         })
     }
@@ -412,10 +418,27 @@ where
         clipboard: &mut dyn Clipboard,
         shell: &mut Shell<'_, Message>,
     ) -> event::Status {
-        self.with_overlay_mut_maybe(|overlay| {
-            overlay.on_event(event, layout, cursor, renderer, clipboard, shell)
-        })
-        .unwrap_or(event::Status::Ignored)
+        let mut is_layout_invalid = false;
+
+        let event_status = self
+            .with_overlay_mut_maybe(|overlay| {
+                let event_status = overlay.on_event(
+                    event, layout, cursor, renderer, clipboard, shell,
+                );
+
+                is_layout_invalid = shell.is_layout_invalid();
+
+                event_status
+            })
+            .unwrap_or(event::Status::Ignored);
+
+        if is_layout_invalid {
+            self.with_overlay_mut(|(_overlay, layout)| {
+                **layout = None;
+            });
+        }
+
+        event_status
     }
 
     fn is_over(
diff --git a/widget/src/lib.rs b/widget/src/lib.rs
index 209dfad9..00e9aaa4 100644
--- a/widget/src/lib.rs
+++ b/widget/src/lib.rs
@@ -2,13 +2,6 @@
 #![doc(
     html_logo_url = "https://raw.githubusercontent.com/iced-rs/iced/9ab6923e943f784985e9ef9ca28b10278297225d/docs/logo.svg"
 )]
-#![forbid(unsafe_code, rust_2018_idioms)]
-#![deny(
-    missing_debug_implementations,
-    missing_docs,
-    unused_results,
-    rustdoc::broken_intra_doc_links
-)]
 #![cfg_attr(docsrs, feature(doc_auto_cfg))]
 pub use iced_renderer as renderer;
 pub use iced_renderer::graphics;
@@ -19,6 +12,7 @@ mod column;
 mod mouse_area;
 mod row;
 mod space;
+mod stack;
 mod themer;
 
 pub mod button;
@@ -85,6 +79,8 @@ pub use slider::Slider;
 #[doc(no_inline)]
 pub use space::Space;
 #[doc(no_inline)]
+pub use stack::Stack;
+#[doc(no_inline)]
 pub use text::Text;
 #[doc(no_inline)]
 pub use text_editor::TextEditor;
diff --git a/widget/src/mouse_area.rs b/widget/src/mouse_area.rs
index 9634e477..d7235cf6 100644
--- a/widget/src/mouse_area.rs
+++ b/widget/src/mouse_area.rs
@@ -232,7 +232,7 @@ where
         );
 
         match (self.interaction, content_interaction) {
-            (Some(interaction), mouse::Interaction::Idle)
+            (Some(interaction), mouse::Interaction::None)
                 if cursor.is_over(layout.bounds()) =>
             {
                 interaction
diff --git a/widget/src/overlay/menu.rs b/widget/src/overlay/menu.rs
index 0364f980..98efe305 100644
--- a/widget/src/overlay/menu.rs
+++ b/widget/src/overlay/menu.rs
@@ -1,5 +1,4 @@
 //! Build and show dropdown menus.
-use crate::container::{self, Container};
 use crate::core::alignment;
 use crate::core::event::{self, Event};
 use crate::core::layout::{self, Layout};
@@ -20,12 +19,15 @@ use crate::scrollable::{self, Scrollable};
 #[allow(missing_debug_implementations)]
 pub struct Menu<
     'a,
+    'b,
     T,
     Message,
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
+    Theme: Catalog,
     Renderer: text::Renderer,
+    'b: 'a,
 {
     state: &'a mut State,
     options: &'a [T],
@@ -38,15 +40,17 @@ pub struct Menu<
     text_line_height: text::LineHeight,
     text_shaping: text::Shaping,
     font: Option<Renderer::Font>,
-    style: &'a Style<'a, Theme>,
+    class: &'a <Theme as Catalog>::Class<'b>,
 }
 
-impl<'a, T, Message, Theme, Renderer> Menu<'a, T, Message, Theme, Renderer>
+impl<'a, 'b, T, Message, Theme, Renderer>
+    Menu<'a, 'b, T, Message, Theme, Renderer>
 where
     T: ToString + Clone,
     Message: 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
+    'b: 'a,
 {
     /// Creates a new [`Menu`] with the given [`State`], a list of options,
     /// the message to produced when an option is selected, and its [`Style`].
@@ -56,7 +60,7 @@ where
         hovered_option: &'a mut Option<usize>,
         on_selected: impl FnMut(T) -> Message + 'a,
         on_option_hovered: Option<&'a dyn Fn(T) -> Message>,
-        style: &'a Style<'a, Theme>,
+        class: &'a <Theme as Catalog>::Class<'b>,
     ) -> Self {
         Menu {
             state,
@@ -70,7 +74,7 @@ where
             text_line_height: text::LineHeight::default(),
             text_shaping: text::Shaping::Basic,
             font: None,
-            style,
+            class,
         }
     }
 
@@ -153,27 +157,29 @@ impl Default for State {
     }
 }
 
-struct Overlay<'a, Message, Theme, Renderer>
+struct Overlay<'a, 'b, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: crate::core::Renderer,
 {
     position: Point,
     state: &'a mut Tree,
-    container: Container<'a, Message, Theme, Renderer>,
+    list: Scrollable<'a, Message, Theme, Renderer>,
     width: f32,
     target_height: f32,
-    style: &'a Style<'a, Theme>,
+    class: &'a <Theme as Catalog>::Class<'b>,
 }
 
-impl<'a, Message, Theme, Renderer> Overlay<'a, Message, Theme, Renderer>
+impl<'a, 'b, Message, Theme, Renderer> Overlay<'a, 'b, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
+    Theme: Catalog + scrollable::Catalog + 'a,
     Renderer: text::Renderer + 'a,
+    'b: 'a,
 {
     pub fn new<T>(
         position: Point,
-        menu: Menu<'a, T, Message, Theme, Renderer>,
+        menu: Menu<'a, 'b, T, Message, Theme, Renderer>,
         target_height: f32,
     ) -> Self
     where
@@ -191,46 +197,43 @@ where
             text_size,
             text_line_height,
             text_shaping,
-            style,
+            class,
         } = menu;
 
-        let container = Container::with_style(
-            Scrollable::with_direction_and_style(
-                List {
-                    options,
-                    hovered_option,
-                    on_selected,
-                    on_option_hovered,
-                    font,
-                    text_size,
-                    text_line_height,
-                    text_shaping,
-                    padding,
-                    style: &style.list,
-                },
-                scrollable::Direction::default(),
-                &style.scrollable,
-            ),
-            container::transparent,
+        let list = Scrollable::with_direction(
+            List {
+                options,
+                hovered_option,
+                on_selected,
+                on_option_hovered,
+                font,
+                text_size,
+                text_line_height,
+                text_shaping,
+                padding,
+                class,
+            },
+            scrollable::Direction::default(),
         );
 
-        state.tree.diff(&container as &dyn Widget<_, _, _>);
+        state.tree.diff(&list as &dyn Widget<_, _, _>);
 
         Self {
             position,
             state: &mut state.tree,
-            container,
+            list,
             width,
             target_height,
-            style,
+            class,
         }
     }
 }
 
-impl<'a, Message, Theme, Renderer>
+impl<'a, 'b, Message, Theme, Renderer>
     crate::core::Overlay<Message, Theme, Renderer>
-    for Overlay<'a, Message, Theme, Renderer>
+    for Overlay<'a, 'b, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn layout(&mut self, renderer: &Renderer, bounds: Size) -> layout::Node {
@@ -251,7 +254,7 @@ where
         )
         .width(self.width);
 
-        let node = self.container.layout(self.state, renderer, &limits);
+        let node = self.list.layout(self.state, renderer, &limits);
         let size = node.size();
 
         node.move_to(if space_below > space_above {
@@ -272,7 +275,7 @@ where
     ) -> event::Status {
         let bounds = layout.bounds();
 
-        self.container.on_event(
+        self.list.on_event(
             self.state, event, layout, cursor, renderer, clipboard, shell,
             &bounds,
         )
@@ -285,7 +288,7 @@ where
         viewport: &Rectangle,
         renderer: &Renderer,
     ) -> mouse::Interaction {
-        self.container
+        self.list
             .mouse_interaction(self.state, layout, cursor, viewport, renderer)
     }
 
@@ -293,30 +296,32 @@ where
         &self,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
     ) {
         let bounds = layout.bounds();
 
-        let appearance = (self.style.list)(theme);
+        let style = Catalog::style(theme, self.class);
 
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: appearance.border,
+                border: style.border,
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
-        self.container
-            .draw(self.state, renderer, theme, style, layout, cursor, &bounds);
+        self.list.draw(
+            self.state, renderer, theme, defaults, layout, cursor, &bounds,
+        );
     }
 }
 
-struct List<'a, T, Message, Theme, Renderer>
+struct List<'a, 'b, T, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     options: &'a [T],
@@ -328,13 +333,14 @@ where
     text_line_height: text::LineHeight,
     text_shaping: text::Shaping,
     font: Option<Renderer::Font>,
-    style: &'a dyn Fn(&Theme) -> Appearance,
+    class: &'a <Theme as Catalog>::Class<'b>,
 }
 
-impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
-    for List<'a, T, Message, Theme, Renderer>
+impl<'a, 'b, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
+    for List<'a, 'b, T, Message, Theme, Renderer>
 where
     T: Clone + ToString,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn size(&self) -> Size<Length> {
@@ -477,7 +483,7 @@ where
         _cursor: mouse::Cursor,
         viewport: &Rectangle,
     ) {
-        let appearance = (self.style)(theme);
+        let style = Catalog::style(theme, self.class);
         let bounds = layout.bounds();
 
         let text_size =
@@ -507,20 +513,20 @@ where
                 renderer.fill_quad(
                     renderer::Quad {
                         bounds: Rectangle {
-                            x: bounds.x + appearance.border.width,
-                            width: bounds.width - appearance.border.width * 2.0,
+                            x: bounds.x + style.border.width,
+                            width: bounds.width - style.border.width * 2.0,
                             ..bounds
                         },
-                        border: Border::rounded(appearance.border.radius),
+                        border: Border::rounded(style.border.radius),
                         ..renderer::Quad::default()
                     },
-                    appearance.selected_background,
+                    style.selected_background,
                 );
             }
 
             renderer.fill_text(
                 Text {
-                    content: &option.to_string(),
+                    content: option.to_string(),
                     bounds: Size::new(f32::INFINITY, bounds.height),
                     size: text_size,
                     line_height: self.text_line_height,
@@ -531,9 +537,9 @@ where
                 },
                 Point::new(bounds.x + self.padding.left, bounds.center_y()),
                 if is_selected {
-                    appearance.selected_text_color
+                    style.selected_text_color
                 } else {
-                    appearance.text_color
+                    style.text_color
                 },
                 *viewport,
             );
@@ -541,23 +547,24 @@ where
     }
 }
 
-impl<'a, T, Message, Theme, Renderer>
-    From<List<'a, T, Message, Theme, Renderer>>
+impl<'a, 'b, T, Message, Theme, Renderer>
+    From<List<'a, 'b, T, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     T: ToString + Clone,
     Message: 'a,
-    Theme: 'a,
+    Theme: 'a + Catalog,
     Renderer: 'a + text::Renderer,
+    'b: 'a,
 {
-    fn from(list: List<'a, T, Message, Theme, Renderer>) -> Self {
+    fn from(list: List<'a, 'b, T, Message, Theme, Renderer>) -> Self {
         Element::new(list)
     }
 }
 
 /// The appearance of a [`Menu`].
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the menu.
     pub background: Background,
     /// The [`Border`] of the menu.
@@ -570,35 +577,43 @@ pub struct Appearance {
     pub selected_background: Background,
 }
 
-/// The style of the different parts of a [`Menu`].
-#[allow(missing_debug_implementations)]
-pub struct Style<'a, Theme> {
-    /// The style of the list of the [`Menu`].
-    pub list: Box<dyn Fn(&Theme) -> Appearance + 'a>,
-    /// The style of the [`Scrollable`] of the [`Menu`].
-    pub scrollable: scrollable::Style<'a, Theme>,
-}
+/// The theme catalog of a [`Menu`].
+pub trait Catalog: scrollable::Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
+
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> <Self as Catalog>::Class<'a>;
 
-/// The default style of a [`Menu`].
-pub trait DefaultStyle: Sized {
-    /// Returns the default style of a [`Menu`].
-    fn default_style() -> Style<'static, Self>;
+    /// The default class for the scrollable of the [`Menu`].
+    fn default_scrollable<'a>() -> <Self as scrollable::Catalog>::Class<'a> {
+        <Self as scrollable::Catalog>::default()
+    }
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &<Self as Catalog>::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style() -> Style<'static, Self> {
-        Style {
-            list: Box::new(default),
-            scrollable: Box::new(scrollable::default),
-        }
+/// A styling function for a [`Menu`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> StyleFn<'a, Self> {
+        Box::new(default)
+    }
+
+    fn style(&self, class: &StyleFn<'_, Self>) -> Style {
+        class(self)
     }
 }
 
 /// The default style of the list of a [`Menu`].
-pub fn default(theme: &Theme) -> Appearance {
+pub fn default(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
-    Appearance {
+    Style {
         background: palette.background.weak.color.into(),
         border: Border {
             width: 1.0,
diff --git a/widget/src/pane_grid.rs b/widget/src/pane_grid.rs
index beac0bd8..acfa9d44 100644
--- a/widget/src/pane_grid.rs
+++ b/widget/src/pane_grid.rs
@@ -30,6 +30,7 @@ pub use split::Split;
 pub use state::State;
 pub use title_bar::TitleBar;
 
+use crate::container;
 use crate::core::event::{self, Event};
 use crate::core::layout;
 use crate::core::mouse;
@@ -39,8 +40,8 @@ use crate::core::touch;
 use crate::core::widget;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Background, Border, Clipboard, Color, Element, Layout, Length, Pixels,
-    Point, Rectangle, Shell, Size, Theme, Vector, Widget,
+    self, Background, Border, Clipboard, Color, Element, Layout, Length,
+    Pixels, Point, Rectangle, Shell, Size, Theme, Vector, Widget,
 };
 
 const DRAG_DEADBAND_DISTANCE: f32 = 10.0;
@@ -101,7 +102,8 @@ pub struct PaneGrid<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     contents: Contents<'a, Content<'a, Message, Theme, Renderer>>,
     width: Length,
@@ -110,12 +112,13 @@ pub struct PaneGrid<
     on_click: Option<Box<dyn Fn(Pane) -> Message + 'a>>,
     on_drag: Option<Box<dyn Fn(DragEvent) -> Message + 'a>>,
     on_resize: Option<(f32, Box<dyn Fn(ResizeEvent) -> Message + 'a>)>,
-    style: Style<'a, Theme>,
+    class: <Theme as Catalog>::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> PaneGrid<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     /// Creates a [`PaneGrid`] with the given [`State`] and view function.
     ///
@@ -124,10 +127,7 @@ where
     pub fn new<T>(
         state: &'a State<T>,
         view: impl Fn(Pane, &'a T, bool) -> Content<'a, Message, Theme, Renderer>,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    ) -> Self {
         let contents = if let Some((pane, pane_state)) =
             state.maximized.and_then(|pane| {
                 state.panes.get(&pane).map(|pane_state| (pane, pane_state))
@@ -158,7 +158,7 @@ where
             on_click: None,
             on_drag: None,
             on_resize: None,
-            style: Box::new(Theme::default_style),
+            class: <Theme as Catalog>::default(),
         }
     }
 
@@ -218,8 +218,23 @@ where
     }
 
     /// Sets the style of the [`PaneGrid`].
-    pub fn style(mut self, style: impl Fn(&Theme) -> Appearance + 'a) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme) -> Style + 'a) -> Self
+    where
+        <Theme as Catalog>::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`PaneGrid`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(
+        mut self,
+        class: impl Into<<Theme as Catalog>::Class<'a>>,
+    ) -> Self {
+        self.class = class.into();
         self
     }
 
@@ -233,7 +248,8 @@ where
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for PaneGrid<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<state::Action>()
@@ -596,7 +612,7 @@ where
         tree: &Tree,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         viewport: &Rectangle,
@@ -677,7 +693,7 @@ where
             None
         };
 
-        let appearance = (self.style)(theme);
+        let style = Catalog::style(theme, &self.class);
 
         for ((id, (content, tree)), pane_layout) in
             contents.zip(layout.children())
@@ -692,7 +708,7 @@ where
                         tree,
                         renderer,
                         theme,
-                        style,
+                        defaults,
                         pane_layout,
                         pane_cursor,
                         viewport,
@@ -710,10 +726,10 @@ where
                             renderer.fill_quad(
                                 renderer::Quad {
                                     bounds,
-                                    border: appearance.hovered_region.border,
+                                    border: style.hovered_region.border,
                                     ..renderer::Quad::default()
                                 },
-                                appearance.hovered_region.background,
+                                style.hovered_region.background,
                             );
                         }
                     }
@@ -723,7 +739,7 @@ where
                         tree,
                         renderer,
                         theme,
-                        style,
+                        defaults,
                         pane_layout,
                         pane_cursor,
                         viewport,
@@ -738,10 +754,10 @@ where
             renderer.fill_quad(
                 renderer::Quad {
                     bounds,
-                    border: appearance.hovered_region.border,
+                    border: style.hovered_region.border,
                     ..renderer::Quad::default()
                 },
-                appearance.hovered_region.background,
+                style.hovered_region.background,
             );
         }
 
@@ -759,7 +775,7 @@ where
                             tree,
                             renderer,
                             theme,
-                            style,
+                            defaults,
                             layout,
                             pane_cursor,
                             viewport,
@@ -772,9 +788,9 @@ where
         if picked_pane.is_none() {
             if let Some((axis, split_region, is_picked)) = picked_split {
                 let highlight = if is_picked {
-                    appearance.picked_split
+                    style.picked_split
                 } else {
-                    appearance.hovered_split
+                    style.hovered_split
                 };
 
                 renderer.fill_quad(
@@ -832,8 +848,8 @@ impl<'a, Message, Theme, Renderer> From<PaneGrid<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
-    Renderer: crate::core::Renderer + 'a,
+    Theme: Catalog + 'a,
+    Renderer: core::Renderer + 'a,
 {
     fn from(
         pane_grid: PaneGrid<'a, Message, Theme, Renderer>,
@@ -1116,7 +1132,7 @@ impl<'a, T> Contents<'a, T> {
 
 /// The appearance of a [`PaneGrid`].
 #[derive(Debug, Clone, Copy, PartialEq)]
-pub struct Appearance {
+pub struct Style {
     /// The appearance of a hovered region highlight.
     pub hovered_region: Highlight,
     /// The appearance of a picked split.
@@ -1145,32 +1161,40 @@ pub struct Line {
     pub width: f32,
 }
 
-/// The style of a [`PaneGrid`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme) -> Appearance + 'a>;
+/// The theme catalog of a [`PaneGrid`].
+pub trait Catalog: container::Catalog {
+    /// The item class of this [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`PaneGrid`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`PaneGrid`].
-    fn default_style(&self) -> Appearance;
+    /// The default class produced by this [`Catalog`].
+    fn default<'a>() -> <Self as Catalog>::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &<Self as Catalog>::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self) -> Appearance {
-        default(self)
+/// A styling function for a [`PaneGrid`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> StyleFn<'a, Self> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self) -> Appearance {
-        *self
+    fn style(&self, class: &StyleFn<'_, Self>) -> Style {
+        class(self)
     }
 }
 
 /// The default style of a [`PaneGrid`].
-pub fn default(theme: &Theme) -> Appearance {
+pub fn default(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
-    Appearance {
+    Style {
         hovered_region: Highlight {
             background: Background::Color(Color {
                 a: 0.5,
diff --git a/widget/src/pane_grid/content.rs b/widget/src/pane_grid/content.rs
index 98f4f99a..30ad52ca 100644
--- a/widget/src/pane_grid/content.rs
+++ b/widget/src/pane_grid/content.rs
@@ -6,7 +6,7 @@ use crate::core::overlay;
 use crate::core::renderer;
 use crate::core::widget::{self, Tree};
 use crate::core::{
-    Clipboard, Element, Layout, Point, Rectangle, Shell, Size, Vector,
+    self, Clipboard, Element, Layout, Point, Rectangle, Shell, Size, Vector,
 };
 use crate::pane_grid::{Draggable, TitleBar};
 
@@ -20,30 +20,29 @@ pub struct Content<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     title_bar: Option<TitleBar<'a, Message, Theme, Renderer>>,
     body: Element<'a, Message, Theme, Renderer>,
-    style: container::Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Content<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     /// Creates a new [`Content`] with the provided body.
-    pub fn new(body: impl Into<Element<'a, Message, Theme, Renderer>>) -> Self
-    where
-        Theme: container::DefaultStyle + 'a,
-    {
+    pub fn new(body: impl Into<Element<'a, Message, Theme, Renderer>>) -> Self {
         Self {
             title_bar: None,
             body: body.into(),
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
-    /// Sets the [`TitleBar`] of this [`Content`].
+    /// Sets the [`TitleBar`] of the [`Content`].
     pub fn title_bar(
         mut self,
         title_bar: TitleBar<'a, Message, Theme, Renderer>,
@@ -53,18 +52,31 @@ where
     }
 
     /// Sets the style of the [`Content`].
+    #[must_use]
     pub fn style(
         mut self,
-        style: impl Fn(&Theme, container::Status) -> container::Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+        style: impl Fn(&Theme) -> container::Style + 'a,
+    ) -> Self
+    where
+        Theme::Class<'a>: From<container::StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as container::StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Content`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
 
 impl<'a, Message, Theme, Renderer> Content<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     pub(super) fn state(&self) -> Tree {
         let children = if let Some(title_bar) = self.title_bar.as_ref() {
@@ -93,7 +105,7 @@ where
 
     /// Draws the [`Content`] with the provided [`Renderer`] and [`Layout`].
     ///
-    /// [`Renderer`]: crate::core::Renderer
+    /// [`Renderer`]: core::Renderer
     pub fn draw(
         &self,
         tree: &Tree,
@@ -107,15 +119,7 @@ where
         let bounds = layout.bounds();
 
         {
-            let style = {
-                let status = if cursor.is_over(bounds) {
-                    container::Status::Hovered
-                } else {
-                    container::Status::Idle
-                };
-
-                (self.style)(theme, status)
-            };
+            let style = theme.style(&self.class);
 
             container::draw_background(renderer, &style, bounds);
         }
@@ -381,7 +385,8 @@ where
 impl<'a, Message, Theme, Renderer> Draggable
     for &Content<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     fn can_be_dragged_at(
         &self,
@@ -403,8 +408,8 @@ impl<'a, T, Message, Theme, Renderer> From<T>
     for Content<'a, Message, Theme, Renderer>
 where
     T: Into<Element<'a, Message, Theme, Renderer>>,
-    Theme: container::DefaultStyle + 'a,
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog + 'a,
+    Renderer: core::Renderer,
 {
     fn from(element: T) -> Self {
         Self::new(element)
diff --git a/widget/src/pane_grid/state.rs b/widget/src/pane_grid/state.rs
index 481cd770..c20c3b9c 100644
--- a/widget/src/pane_grid/state.rs
+++ b/widget/src/pane_grid/state.rs
@@ -6,7 +6,7 @@ use crate::pane_grid::{
     Axis, Configuration, Direction, Edge, Node, Pane, Region, Split, Target,
 };
 
-use std::collections::HashMap;
+use rustc_hash::FxHashMap;
 
 /// The state of a [`PaneGrid`].
 ///
@@ -25,7 +25,7 @@ pub struct State<T> {
     /// The panes of the [`PaneGrid`].
     ///
     /// [`PaneGrid`]: super::PaneGrid
-    pub panes: HashMap<Pane, T>,
+    pub panes: FxHashMap<Pane, T>,
 
     /// The internal state of the [`PaneGrid`].
     ///
@@ -52,7 +52,7 @@ impl<T> State<T> {
 
     /// Creates a new [`State`] with the given [`Configuration`].
     pub fn with_configuration(config: impl Into<Configuration<T>>) -> Self {
-        let mut panes = HashMap::new();
+        let mut panes = FxHashMap::default();
 
         let internal =
             Internal::from_configuration(&mut panes, config.into(), 0);
@@ -353,7 +353,7 @@ impl Internal {
     ///
     /// [`PaneGrid`]: super::PaneGrid
     pub fn from_configuration<T>(
-        panes: &mut HashMap<Pane, T>,
+        panes: &mut FxHashMap<Pane, T>,
         content: Configuration<T>,
         next_id: usize,
     ) -> Self {
diff --git a/widget/src/pane_grid/title_bar.rs b/widget/src/pane_grid/title_bar.rs
index 8dfea6e3..c2eeebb7 100644
--- a/widget/src/pane_grid/title_bar.rs
+++ b/widget/src/pane_grid/title_bar.rs
@@ -6,7 +6,8 @@ use crate::core::overlay;
 use crate::core::renderer;
 use crate::core::widget::{self, Tree};
 use crate::core::{
-    Clipboard, Element, Layout, Padding, Point, Rectangle, Shell, Size, Vector,
+    self, Clipboard, Element, Layout, Padding, Point, Rectangle, Shell, Size,
+    Vector,
 };
 
 /// The title bar of a [`Pane`].
@@ -19,32 +20,31 @@ pub struct TitleBar<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     content: Element<'a, Message, Theme, Renderer>,
     controls: Option<Element<'a, Message, Theme, Renderer>>,
     padding: Padding,
     always_show_controls: bool,
-    style: container::Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> TitleBar<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     /// Creates a new [`TitleBar`] with the given content.
     pub fn new(
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
-    ) -> Self
-    where
-        Theme: container::DefaultStyle + 'a,
-    {
+    ) -> Self {
         Self {
             content: content.into(),
             controls: None,
             padding: Padding::ZERO,
             always_show_controls: false,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -63,15 +63,6 @@ where
         self
     }
 
-    /// Sets the style of the [`TitleBar`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, container::Status) -> container::Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
-        self
-    }
-
     /// Sets whether or not the [`controls`] attached to this [`TitleBar`] are
     /// always visible.
     ///
@@ -84,11 +75,33 @@ where
         self.always_show_controls = true;
         self
     }
+
+    /// Sets the style of the [`TitleBar`].
+    #[must_use]
+    pub fn style(
+        mut self,
+        style: impl Fn(&Theme) -> container::Style + 'a,
+    ) -> Self
+    where
+        Theme::Class<'a>: From<container::StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as container::StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`TitleBar`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
 }
 
 impl<'a, Message, Theme, Renderer> TitleBar<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: container::Catalog,
+    Renderer: core::Renderer,
 {
     pub(super) fn state(&self) -> Tree {
         let children = if let Some(controls) = self.controls.as_ref() {
@@ -117,7 +130,7 @@ where
 
     /// Draws the [`TitleBar`] with the provided [`Renderer`] and [`Layout`].
     ///
-    /// [`Renderer`]: crate::core::Renderer
+    /// [`Renderer`]: core::Renderer
     pub fn draw(
         &self,
         tree: &Tree,
@@ -130,16 +143,7 @@ where
         show_controls: bool,
     ) {
         let bounds = layout.bounds();
-
-        let style = {
-            let status = if cursor.is_over(bounds) {
-                container::Status::Hovered
-            } else {
-                container::Status::Idle
-            };
-
-            (self.style)(theme, status)
-        };
+        let style = theme.style(&self.class);
 
         let inherited_style = renderer::Style {
             text_color: style.text_color.unwrap_or(inherited_style.text_color),
diff --git a/widget/src/pick_list.rs b/widget/src/pick_list.rs
index 52d54397..edccfdaa 100644
--- a/widget/src/pick_list.rs
+++ b/widget/src/pick_list.rs
@@ -32,6 +32,7 @@ pub struct PickList<
     T: ToString + PartialEq + Clone,
     L: Borrow<[T]> + 'a,
     V: Borrow<T> + 'a,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     on_select: Box<dyn Fn(T) -> Message + 'a>,
@@ -47,7 +48,8 @@ pub struct PickList<
     text_shaping: text::Shaping,
     font: Option<Renderer::Font>,
     handle: Handle<Renderer::Font>,
-    style: Style<'a, Theme>,
+    class: <Theme as Catalog>::Class<'a>,
+    menu_class: <Theme as menu::Catalog>::Class<'a>,
 }
 
 impl<'a, T, L, V, Message, Theme, Renderer>
@@ -57,6 +59,7 @@ where
     L: Borrow<[T]> + 'a,
     V: Borrow<T> + 'a,
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// Creates a new [`PickList`] with the given list of options, the current
@@ -65,10 +68,7 @@ where
         options: L,
         selected: Option<V>,
         on_select: impl Fn(T) -> Message + 'a,
-    ) -> Self
-    where
-        Theme: DefaultStyle,
-    {
+    ) -> Self {
         Self {
             on_select: Box::new(on_select),
             on_open: None,
@@ -83,7 +83,8 @@ where
             text_shaping: text::Shaping::Basic,
             font: None,
             handle: Handle::default(),
-            style: Theme::default_style(),
+            class: <Theme as Catalog>::default(),
+            menu_class: <Theme as Catalog>::default_menu(),
         }
     }
 
@@ -151,8 +152,23 @@ where
     }
 
     /// Sets the style of the [`PickList`].
-    pub fn style(mut self, style: impl Into<Style<'a, Theme>>) -> Self {
-        self.style = style.into();
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        <Theme as Catalog>::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`PickList`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(
+        mut self,
+        class: impl Into<<Theme as Catalog>::Class<'a>>,
+    ) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -164,6 +180,7 @@ where
     L: Borrow<[T]>,
     V: Borrow<T>,
     Message: Clone + 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn tag(&self) -> tree::Tag {
@@ -409,15 +426,15 @@ where
             Status::Active
         };
 
-        let appearance = (self.style.field)(theme, status);
+        let style = Catalog::style(theme, &self.class, status);
 
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: appearance.border,
+                border: style.border,
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
         let handle = match &self.handle {
@@ -462,7 +479,7 @@ where
 
             renderer.fill_text(
                 Text {
-                    content: &code_point.to_string(),
+                    content: code_point.to_string(),
                     size,
                     line_height,
                     font,
@@ -478,14 +495,14 @@ where
                     bounds.x + bounds.width - self.padding.right,
                     bounds.center_y(),
                 ),
-                appearance.handle_color,
+                style.handle_color,
                 *viewport,
             );
         }
 
         let label = selected.map(ToString::to_string);
 
-        if let Some(label) = label.as_deref().or(self.placeholder.as_deref()) {
+        if let Some(label) = label.or_else(|| self.placeholder.clone()) {
             let text_size =
                 self.text_size.unwrap_or_else(|| renderer.default_size());
 
@@ -505,9 +522,9 @@ where
                 },
                 Point::new(bounds.x + self.padding.left, bounds.center_y()),
                 if is_selected {
-                    appearance.text_color
+                    style.text_color
                 } else {
-                    appearance.placeholder_color
+                    style.placeholder_color
                 },
                 *viewport,
             );
@@ -539,7 +556,7 @@ where
                     (on_select)(option)
                 },
                 None,
-                &self.style.menu,
+                &self.menu_class,
             )
             .width(bounds.width)
             .padding(self.padding)
@@ -565,7 +582,7 @@ where
     L: Borrow<[T]> + 'a,
     V: Borrow<T> + 'a,
     Message: Clone + 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(
@@ -662,7 +679,7 @@ pub enum Status {
 
 /// The appearance of a pick list.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The text [`Color`] of the pick list.
     pub text_color: Color,
     /// The placeholder [`Color`] of the pick list.
@@ -675,36 +692,49 @@ pub struct Appearance {
     pub border: Border,
 }
 
-/// The styles of the different parts of a [`PickList`].
-#[allow(missing_debug_implementations)]
-pub struct Style<'a, Theme> {
-    /// The style of the [`PickList`] itself.
-    pub field: Box<dyn Fn(&Theme, Status) -> Appearance + 'a>,
+/// The theme catalog of a [`PickList`].
+pub trait Catalog: menu::Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-    /// The style of the [`Menu`] of the pick list.
-    pub menu: menu::Style<'a, Theme>,
-}
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> <Self as Catalog>::Class<'a>;
 
-/// The default style of a [`PickList`].
-pub trait DefaultStyle: Sized {
-    /// Returns the default style of a [`PickList`].
-    fn default_style() -> Style<'static, Self>;
+    /// The default class for the menu of the [`PickList`].
+    fn default_menu<'a>() -> <Self as menu::Catalog>::Class<'a> {
+        <Self as menu::Catalog>::default()
+    }
+
+    /// The [`Style`] of a class with the given status.
+    fn style(
+        &self,
+        class: &<Self as Catalog>::Class<'_>,
+        status: Status,
+    ) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style() -> Style<'static, Self> {
-        Style {
-            field: Box::new(default),
-            menu: menu::DefaultStyle::default_style(),
-        }
+/// A styling function for a [`PickList`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> StyleFn<'a, Self> {
+        Box::new(default)
+    }
+
+    fn style(&self, class: &StyleFn<'_, Self>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of the field of a [`PickList`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
-    let active = Appearance {
+    let active = Style {
         text_color: palette.background.weak.text,
         background: palette.background.weak.color.into(),
         placeholder_color: palette.background.strong.color,
@@ -718,7 +748,7 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
 
     match status {
         Status::Active => active,
-        Status::Hovered | Status::Opened => Appearance {
+        Status::Hovered | Status::Opened => Style {
             border: Border {
                 color: palette.primary.strong.color,
                 ..active.border
diff --git a/widget/src/progress_bar.rs b/widget/src/progress_bar.rs
index 38d8da85..e7821b43 100644
--- a/widget/src/progress_bar.rs
+++ b/widget/src/progress_bar.rs
@@ -4,7 +4,8 @@ use crate::core::mouse;
 use crate::core::renderer;
 use crate::core::widget::Tree;
 use crate::core::{
-    Background, Border, Element, Layout, Length, Rectangle, Size, Theme, Widget,
+    self, Background, Border, Element, Layout, Length, Rectangle, Size, Theme,
+    Widget,
 };
 
 use std::ops::RangeInclusive;
@@ -22,15 +23,21 @@ use std::ops::RangeInclusive;
 ///
 /// ![Progress bar drawn with `iced_wgpu`](https://user-images.githubusercontent.com/18618951/71662391-a316c200-2d51-11ea-9cef-52758cab85e3.png)
 #[allow(missing_debug_implementations)]
-pub struct ProgressBar<'a, Theme = crate::Theme> {
+pub struct ProgressBar<'a, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     range: RangeInclusive<f32>,
     value: f32,
     width: Length,
     height: Option<Length>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
-impl<'a, Theme> ProgressBar<'a, Theme> {
+impl<'a, Theme> ProgressBar<'a, Theme>
+where
+    Theme: Catalog,
+{
     /// The default height of a [`ProgressBar`].
     pub const DEFAULT_HEIGHT: f32 = 30.0;
 
@@ -39,16 +46,13 @@ impl<'a, Theme> ProgressBar<'a, Theme> {
     /// It expects:
     ///   * an inclusive range of possible values
     ///   * the current value of the [`ProgressBar`]
-    pub fn new(range: RangeInclusive<f32>, value: f32) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn new(range: RangeInclusive<f32>, value: f32) -> Self {
         ProgressBar {
             value: value.clamp(*range.start(), *range.end()),
             range,
             width: Length::Fill,
             height: None,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -65,8 +69,20 @@ impl<'a, Theme> ProgressBar<'a, Theme> {
     }
 
     /// Sets the style of the [`ProgressBar`].
-    pub fn style(mut self, style: impl Fn(&Theme) -> Appearance + 'a) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`ProgressBar`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -74,7 +90,8 @@ impl<'a, Theme> ProgressBar<'a, Theme> {
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for ProgressBar<'a, Theme>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     fn size(&self) -> Size<Length> {
         Size {
@@ -116,15 +133,15 @@ where
                 / (range_end - range_start)
         };
 
-        let appearance = (self.style)(theme);
+        let style = theme.style(&self.class);
 
         renderer.fill_quad(
             renderer::Quad {
                 bounds: Rectangle { ..bounds },
-                border: appearance.border,
+                border: style.border,
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
         if active_progress_width > 0.0 {
@@ -134,10 +151,10 @@ where
                         width: active_progress_width,
                         ..bounds
                     },
-                    border: Border::rounded(appearance.border.radius),
+                    border: Border::rounded(style.border.radius),
                     ..renderer::Quad::default()
                 },
-                appearance.bar,
+                style.bar,
             );
         }
     }
@@ -147,8 +164,8 @@ impl<'a, Message, Theme, Renderer> From<ProgressBar<'a, Theme>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
-    Renderer: 'a + crate::core::Renderer,
+    Theme: 'a + Catalog,
+    Renderer: 'a + core::Renderer,
 {
     fn from(
         progress_bar: ProgressBar<'a, Theme>,
@@ -159,7 +176,7 @@ where
 
 /// The appearance of a progress bar.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the progress bar.
     pub background: Background,
     /// The [`Background`] of the bar of the progress bar.
@@ -168,29 +185,37 @@ pub struct Appearance {
     pub border: Border,
 }
 
-/// The style of a [`ProgressBar`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme) -> Appearance + 'a>;
+/// The theme catalog of a [`ProgressBar`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
+
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
 
-/// The default style of a [`ProgressBar`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`ProgressBar`].
-    fn default_style(&self) -> Appearance;
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self) -> Appearance {
-        primary(self)
+/// A styling function for a [`ProgressBar`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(primary)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>) -> Style {
+        class(self)
     }
 }
 
 /// The primary style of a [`ProgressBar`].
-pub fn primary(theme: &Theme) -> Appearance {
+pub fn primary(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
     styled(
@@ -200,7 +225,7 @@ pub fn primary(theme: &Theme) -> Appearance {
 }
 
 /// The secondary style of a [`ProgressBar`].
-pub fn secondary(theme: &Theme) -> Appearance {
+pub fn secondary(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
     styled(
@@ -210,14 +235,14 @@ pub fn secondary(theme: &Theme) -> Appearance {
 }
 
 /// The success style of a [`ProgressBar`].
-pub fn success(theme: &Theme) -> Appearance {
+pub fn success(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
     styled(palette.background.strong.color, palette.success.base.color)
 }
 
 /// The danger style of a [`ProgressBar`].
-pub fn danger(theme: &Theme) -> Appearance {
+pub fn danger(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
     styled(palette.background.strong.color, palette.danger.base.color)
@@ -226,8 +251,8 @@ pub fn danger(theme: &Theme) -> Appearance {
 fn styled(
     background: impl Into<Background>,
     bar: impl Into<Background>,
-) -> Appearance {
-    Appearance {
+) -> Style {
+    Style {
         background: background.into(),
         bar: bar.into(),
         border: Border::rounded(2),
diff --git a/widget/src/qr_code.rs b/widget/src/qr_code.rs
index 90c0c970..e064aada 100644
--- a/widget/src/qr_code.rs
+++ b/widget/src/qr_code.rs
@@ -8,7 +8,6 @@ use crate::core::{
     Color, Element, Layout, Length, Point, Rectangle, Size, Theme, Vector,
     Widget,
 };
-use crate::graphics::geometry::Renderer as _;
 use crate::Renderer;
 
 use std::cell::RefCell;
@@ -20,22 +19,25 @@ const QUIET_ZONE: usize = 2;
 /// A type of matrix barcode consisting of squares arranged in a grid which
 /// can be read by an imaging device, such as a camera.
 #[allow(missing_debug_implementations)]
-pub struct QRCode<'a, Theme = crate::Theme> {
+pub struct QRCode<'a, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     data: &'a Data,
     cell_size: u16,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
-impl<'a, Theme> QRCode<'a, Theme> {
+impl<'a, Theme> QRCode<'a, Theme>
+where
+    Theme: Catalog,
+{
     /// Creates a new [`QRCode`] with the provided [`Data`].
-    pub fn new(data: &'a Data) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn new(data: &'a Data) -> Self {
         Self {
             data,
             cell_size: DEFAULT_CELL_SIZE,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -46,14 +48,27 @@ impl<'a, Theme> QRCode<'a, Theme> {
     }
 
     /// Sets the style of the [`QRCode`].
-    pub fn style(mut self, style: impl Fn(&Theme) -> Appearance + 'a) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`QRCode`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
 
-impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
-    for QRCode<'a, Theme>
+impl<'a, Message, Theme> Widget<Message, Theme, Renderer> for QRCode<'a, Theme>
+where
+    Theme: Catalog,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<State>()
@@ -97,13 +112,13 @@ impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
         let bounds = layout.bounds();
         let side_length = self.data.width + 2 * QUIET_ZONE;
 
-        let appearance = (self.style)(theme);
-        let mut last_appearance = state.last_appearance.borrow_mut();
+        let style = theme.style(&self.class);
+        let mut last_style = state.last_style.borrow_mut();
 
-        if Some(appearance) != *last_appearance {
+        if Some(style) != *last_style {
             self.data.cache.clear();
 
-            *last_appearance = Some(appearance);
+            *last_style = Some(style);
         }
 
         // Reuse cache if possible
@@ -115,7 +130,7 @@ impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
             frame.fill_rectangle(
                 Point::ORIGIN,
                 Size::new(side_length as f32, side_length as f32),
-                appearance.background,
+                style.background,
             );
 
             // Avoid drawing on the quiet zone
@@ -134,7 +149,7 @@ impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
                     frame.fill_rectangle(
                         Point::new(column as f32, row as f32),
                         Size::UNIT,
-                        appearance.cell,
+                        style.cell,
                     );
                 });
         });
@@ -142,7 +157,9 @@ impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
         renderer.with_translation(
             bounds.position() - Point::ORIGIN,
             |renderer| {
-                renderer.draw(vec![geometry]);
+                use crate::graphics::geometry::Renderer as _;
+
+                renderer.draw_geometry(geometry);
             },
         );
     }
@@ -151,7 +168,7 @@ impl<'a, Message, Theme> Widget<Message, Theme, Renderer>
 impl<'a, Message, Theme> From<QRCode<'a, Theme>>
     for Element<'a, Message, Theme, Renderer>
 where
-    Theme: 'a,
+    Theme: Catalog + 'a,
 {
     fn from(qr_code: QRCode<'a, Theme>) -> Self {
         Self::new(qr_code)
@@ -165,7 +182,7 @@ where
 pub struct Data {
     contents: Vec<qrcode::Color>,
     width: usize,
-    cache: canvas::Cache,
+    cache: canvas::Cache<Renderer>,
 }
 
 impl Data {
@@ -323,44 +340,50 @@ impl From<qrcode::types::QrError> for Error {
 
 #[derive(Default)]
 struct State {
-    last_appearance: RefCell<Option<Appearance>>,
+    last_style: RefCell<Option<Style>>,
 }
 
 /// The appearance of a QR code.
 #[derive(Debug, Clone, Copy, PartialEq)]
-pub struct Appearance {
+pub struct Style {
     /// The color of the QR code data cells
     pub cell: Color,
     /// The color of the QR code background
     pub background: Color,
 }
 
-/// The style of a [`QRCode`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme) -> Appearance + 'a>;
+/// The theme catalog of a [`QRCode`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`QRCode`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`QRCode`].
-    fn default_style(&self) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self) -> Appearance {
-        default(self)
+/// A styling function for a [`QRCode`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>) -> Style {
+        class(self)
     }
 }
 
 /// The default style of a [`QRCode`].
-pub fn default(theme: &Theme) -> Appearance {
+pub fn default(theme: &Theme) -> Style {
     let palette = theme.palette();
 
-    Appearance {
+    Style {
         cell: palette.text,
         background: palette.background,
     }
diff --git a/widget/src/radio.rs b/widget/src/radio.rs
index a7b7dd03..6b22961d 100644
--- a/widget/src/radio.rs
+++ b/widget/src/radio.rs
@@ -69,6 +69,7 @@ use crate::core::{
 #[allow(missing_debug_implementations)]
 pub struct Radio<'a, Message, Theme = crate::Theme, Renderer = crate::Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     is_selected: bool,
@@ -81,12 +82,13 @@ where
     text_line_height: text::LineHeight,
     text_shaping: text::Shaping,
     font: Option<Renderer::Font>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Radio<'a, Message, Theme, Renderer>
 where
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// The default size of a [`Radio`] button.
@@ -110,7 +112,6 @@ where
         f: F,
     ) -> Self
     where
-        Theme: DefaultStyle + 'a,
         V: Eq + Copy,
         F: FnOnce(V) -> Message,
     {
@@ -125,7 +126,7 @@ where
             text_line_height: text::LineHeight::default(),
             text_shaping: text::Shaping::Basic,
             font: None,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -175,11 +176,20 @@ where
     }
 
     /// Sets the style of the [`Radio`] button.
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Radio`] button.
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -188,6 +198,7 @@ impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Radio<'a, Message, Theme, Renderer>
 where
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn tag(&self) -> tree::Tag {
@@ -284,7 +295,7 @@ where
         tree: &Tree,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         viewport: &Rectangle,
@@ -300,7 +311,7 @@ where
             Status::Active { is_selected }
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
         {
             let layout = children.next().unwrap();
@@ -314,12 +325,12 @@ where
                     bounds,
                     border: Border {
                         radius: (size / 2.0).into(),
-                        width: appearance.border_width,
-                        color: appearance.border_color,
+                        width: style.border_width,
+                        color: style.border_color,
                     },
                     ..renderer::Quad::default()
                 },
-                appearance.background,
+                style.background,
             );
 
             if self.is_selected {
@@ -334,7 +345,7 @@ where
                         border: Border::rounded(dot_size / 2.0),
                         ..renderer::Quad::default()
                     },
-                    appearance.dot_color,
+                    style.dot_color,
                 );
             }
         }
@@ -344,11 +355,11 @@ where
 
             crate::text::draw(
                 renderer,
-                style,
+                defaults,
                 label_layout,
                 tree.state.downcast_ref(),
-                crate::text::Appearance {
-                    color: appearance.text_color,
+                crate::text::Style {
+                    color: style.text_color,
                 },
                 viewport,
             );
@@ -360,7 +371,7 @@ impl<'a, Message, Theme, Renderer> From<Radio<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a + Clone,
-    Theme: 'a,
+    Theme: 'a + Catalog,
     Renderer: 'a + text::Renderer,
 {
     fn from(
@@ -387,7 +398,7 @@ pub enum Status {
 
 /// The appearance of a radio button.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the radio button.
     pub background: Background,
     /// The [`Color`] of the dot of the radio button.
@@ -400,32 +411,38 @@ pub struct Appearance {
     pub text_color: Option<Color>,
 }
 
-/// The style of a [`Radio`] button.
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Radio`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Radio`] button.
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Radio`] button.
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`Radio`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`Radio`] button.
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
-    let active = Appearance {
+    let active = Style {
         background: Color::TRANSPARENT.into(),
         dot_color: palette.primary.strong.color,
         border_width: 1.0,
@@ -435,7 +452,7 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
 
     match status {
         Status::Active { .. } => active,
-        Status::Hovered { .. } => Appearance {
+        Status::Hovered { .. } => Style {
             dot_color: palette.primary.strong.color,
             background: palette.primary.weak.color.into(),
             ..active
diff --git a/widget/src/row.rs b/widget/src/row.rs
index 47feff9c..fa352171 100644
--- a/widget/src/row.rs
+++ b/widget/src/row.rs
@@ -31,11 +31,18 @@ where
         Self::from_vec(Vec::new())
     }
 
+    /// Creates a [`Row`] with the given capacity.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self::from_vec(Vec::with_capacity(capacity))
+    }
+
     /// Creates a [`Row`] with the given elements.
     pub fn with_children(
         children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
     ) -> Self {
-        Self::new().extend(children)
+        let iterator = children.into_iter();
+
+        Self::with_capacity(iterator.size_hint().0).extend(iterator)
     }
 
     /// Creates a [`Row`] from an already allocated [`Vec`].
diff --git a/widget/src/rule.rs b/widget/src/rule.rs
index 9fa5f74f..1a536d2f 100644
--- a/widget/src/rule.rs
+++ b/widget/src/rule.rs
@@ -1,4 +1,5 @@
 //! Display a horizontal or vertical rule for dividing content.
+use crate::core;
 use crate::core::border::{self, Border};
 use crate::core::layout;
 use crate::core::mouse;
@@ -10,43 +11,55 @@ use crate::core::{
 
 /// Display a horizontal or vertical rule for dividing content.
 #[allow(missing_debug_implementations)]
-pub struct Rule<'a, Theme = crate::Theme> {
+pub struct Rule<'a, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     width: Length,
     height: Length,
     is_horizontal: bool,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
-impl<'a, Theme> Rule<'a, Theme> {
+impl<'a, Theme> Rule<'a, Theme>
+where
+    Theme: Catalog,
+{
     /// Creates a horizontal [`Rule`] with the given height.
-    pub fn horizontal(height: impl Into<Pixels>) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn horizontal(height: impl Into<Pixels>) -> Self {
         Rule {
             width: Length::Fill,
             height: Length::Fixed(height.into().0),
             is_horizontal: true,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
     /// Creates a vertical [`Rule`] with the given width.
-    pub fn vertical(width: impl Into<Pixels>) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn vertical(width: impl Into<Pixels>) -> Self {
         Rule {
             width: Length::Fixed(width.into().0),
             height: Length::Fill,
             is_horizontal: false,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
     /// Sets the style of the [`Rule`].
-    pub fn style(mut self, style: impl Fn(&Theme) -> Appearance + 'a) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Rule`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -54,7 +67,8 @@ impl<'a, Theme> Rule<'a, Theme> {
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Rule<'a, Theme>
 where
-    Renderer: crate::core::Renderer,
+    Renderer: core::Renderer,
+    Theme: Catalog,
 {
     fn size(&self) -> Size<Length> {
         Size {
@@ -83,35 +97,34 @@ where
         _viewport: &Rectangle,
     ) {
         let bounds = layout.bounds();
-        let appearance = (self.style)(theme);
+        let style = theme.style(&self.class);
 
         let bounds = if self.is_horizontal {
             let line_y = (bounds.y + (bounds.height / 2.0)
-                - (appearance.width as f32 / 2.0))
+                - (style.width as f32 / 2.0))
                 .round();
 
-            let (offset, line_width) = appearance.fill_mode.fill(bounds.width);
+            let (offset, line_width) = style.fill_mode.fill(bounds.width);
             let line_x = bounds.x + offset;
 
             Rectangle {
                 x: line_x,
                 y: line_y,
                 width: line_width,
-                height: appearance.width as f32,
+                height: style.width as f32,
             }
         } else {
             let line_x = (bounds.x + (bounds.width / 2.0)
-                - (appearance.width as f32 / 2.0))
+                - (style.width as f32 / 2.0))
                 .round();
 
-            let (offset, line_height) =
-                appearance.fill_mode.fill(bounds.height);
+            let (offset, line_height) = style.fill_mode.fill(bounds.height);
             let line_y = bounds.y + offset;
 
             Rectangle {
                 x: line_x,
                 y: line_y,
-                width: appearance.width as f32,
+                width: style.width as f32,
                 height: line_height,
             }
         };
@@ -119,10 +132,10 @@ where
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: Border::rounded(appearance.radius),
+                border: Border::rounded(style.radius),
                 ..renderer::Quad::default()
             },
-            appearance.color,
+            style.color,
         );
     }
 }
@@ -131,8 +144,8 @@ impl<'a, Message, Theme, Renderer> From<Rule<'a, Theme>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
-    Renderer: 'a + crate::core::Renderer,
+    Theme: 'a + Catalog,
+    Renderer: 'a + core::Renderer,
 {
     fn from(rule: Rule<'a, Theme>) -> Element<'a, Message, Theme, Renderer> {
         Element::new(rule)
@@ -141,7 +154,7 @@ where
 
 /// The appearance of a rule.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The color of the rule.
     pub color: Color,
     /// The width (thickness) of the rule line.
@@ -216,32 +229,40 @@ impl FillMode {
     }
 }
 
-/// The style of a [`Rule`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme) -> Appearance + 'a>;
+/// The theme catalog of a [`Rule`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Rule`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Rule`].
-    fn default_style(&self) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self) -> Appearance {
-        default(self)
+/// A styling function for a [`Rule`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>) -> Style {
+        class(self)
     }
 }
 
 /// The default styling of a [`Rule`].
-pub fn default(theme: &Theme) -> Appearance {
+pub fn default(theme: &Theme) -> Style {
     let palette = theme.extended_palette();
 
-    Appearance {
+    Style {
         color: palette.background.strong.color,
         width: 1,
         radius: 0.0.into(),
diff --git a/widget/src/scrollable.rs b/widget/src/scrollable.rs
index c03bbb7d..6fc00f87 100644
--- a/widget/src/scrollable.rs
+++ b/widget/src/scrollable.rs
@@ -12,8 +12,8 @@ use crate::core::widget;
 use crate::core::widget::operation::{self, Operation};
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Background, Border, Clipboard, Color, Element, Layout, Length, Pixels,
-    Point, Rectangle, Shell, Size, Theme, Vector, Widget,
+    self, Background, Border, Clipboard, Color, Element, Layout, Length,
+    Pixels, Point, Rectangle, Shell, Size, Theme, Vector, Widget,
 };
 use crate::runtime::Command;
 
@@ -28,7 +28,8 @@ pub struct Scrollable<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     id: Option<Id>,
     width: Length,
@@ -36,20 +37,18 @@ pub struct Scrollable<
     direction: Direction,
     content: Element<'a, Message, Theme, Renderer>,
     on_scroll: Option<Box<dyn Fn(Viewport) -> Message + 'a>>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Scrollable<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     /// Creates a new vertical [`Scrollable`].
     pub fn new(
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    ) -> Self {
         Self::with_direction(content, Direction::default())
     }
 
@@ -57,18 +56,6 @@ where
     pub fn with_direction(
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
         direction: Direction,
-    ) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
-        Self::with_direction_and_style(content, direction, Theme::default_style)
-    }
-
-    /// Creates a new [`Scrollable`] with the given [`Direction`] and style.
-    pub fn with_direction_and_style(
-        content: impl Into<Element<'a, Message, Theme, Renderer>>,
-        direction: Direction,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
     ) -> Self {
         let content = content.into();
 
@@ -91,7 +78,7 @@ where
             direction,
             content,
             on_scroll: None,
-            style: Box::new(style),
+            class: Theme::default(),
         }
     }
 
@@ -121,12 +108,21 @@ where
         self
     }
 
-    /// Sets the style of the [`Scrollable`] .
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    /// Sets the style of this [`Scrollable`].
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Scrollable`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -237,7 +233,8 @@ pub enum Alignment {
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Scrollable<'a, Message, Theme, Renderer>
 where
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<State>()
@@ -353,6 +350,148 @@ where
         let (mouse_over_y_scrollbar, mouse_over_x_scrollbar) =
             scrollbars.is_mouse_over(cursor);
 
+        if let Some(scroller_grabbed_at) = state.y_scroller_grabbed_at {
+            match event {
+                Event::Mouse(mouse::Event::CursorMoved { .. })
+                | Event::Touch(touch::Event::FingerMoved { .. }) => {
+                    if let Some(scrollbar) = scrollbars.y {
+                        let Some(cursor_position) = cursor.position() else {
+                            return event::Status::Ignored;
+                        };
+
+                        state.scroll_y_to(
+                            scrollbar.scroll_percentage_y(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        let _ = notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+
+                        return event::Status::Captured;
+                    }
+                }
+                _ => {}
+            }
+        } else if mouse_over_y_scrollbar {
+            match event {
+                Event::Mouse(mouse::Event::ButtonPressed(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerPressed { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
+                        scrollbars.grab_y_scroller(cursor_position),
+                        scrollbars.y,
+                    ) {
+                        state.scroll_y_to(
+                            scrollbar.scroll_percentage_y(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        state.y_scroller_grabbed_at = Some(scroller_grabbed_at);
+
+                        let _ = notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+                    }
+
+                    return event::Status::Captured;
+                }
+                _ => {}
+            }
+        }
+
+        if let Some(scroller_grabbed_at) = state.x_scroller_grabbed_at {
+            match event {
+                Event::Mouse(mouse::Event::CursorMoved { .. })
+                | Event::Touch(touch::Event::FingerMoved { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let Some(scrollbar) = scrollbars.x {
+                        state.scroll_x_to(
+                            scrollbar.scroll_percentage_x(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        let _ = notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+                    }
+
+                    return event::Status::Captured;
+                }
+                _ => {}
+            }
+        } else if mouse_over_x_scrollbar {
+            match event {
+                Event::Mouse(mouse::Event::ButtonPressed(
+                    mouse::Button::Left,
+                ))
+                | Event::Touch(touch::Event::FingerPressed { .. }) => {
+                    let Some(cursor_position) = cursor.position() else {
+                        return event::Status::Ignored;
+                    };
+
+                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
+                        scrollbars.grab_x_scroller(cursor_position),
+                        scrollbars.x,
+                    ) {
+                        state.scroll_x_to(
+                            scrollbar.scroll_percentage_x(
+                                scroller_grabbed_at,
+                                cursor_position,
+                            ),
+                            bounds,
+                            content_bounds,
+                        );
+
+                        state.x_scroller_grabbed_at = Some(scroller_grabbed_at);
+
+                        let _ = notify_on_scroll(
+                            state,
+                            &self.on_scroll,
+                            bounds,
+                            content_bounds,
+                            shell,
+                        );
+
+                        return event::Status::Captured;
+                    }
+                }
+                _ => {}
+            }
+        }
+
         let mut event_status = {
             let cursor = match cursor_over_scrollable {
                 Some(cursor_position)
@@ -425,7 +564,9 @@ where
                 let delta = match delta {
                     mouse::ScrollDelta::Lines { x, y } => {
                         // TODO: Configurable speed/friction (?)
-                        let movement = if state.keyboard_modifiers.shift() {
+                        let movement = if !cfg!(target_os = "macos") // macOS automatically inverts the axes when Shift is pressed
+                            && state.keyboard_modifiers.shift()
+                        {
                             Vector::new(y, x)
                         } else {
                             Vector::new(x, y)
@@ -438,15 +579,17 @@ where
 
                 state.scroll(delta, self.direction, bounds, content_bounds);
 
-                notify_on_scroll(
+                event_status = if notify_on_scroll(
                     state,
                     &self.on_scroll,
                     bounds,
                     content_bounds,
                     shell,
-                );
-
-                event_status = event::Status::Captured;
+                ) {
+                    event::Status::Captured
+                } else {
+                    event::Status::Ignored
+                };
             }
             Event::Touch(event)
                 if state.scroll_area_touched_at.is_some()
@@ -484,7 +627,8 @@ where
                             state.scroll_area_touched_at =
                                 Some(cursor_position);
 
-                            notify_on_scroll(
+                            // TODO: bubble up touch movements if not consumed.
+                            let _ = notify_on_scroll(
                                 state,
                                 &self.on_scroll,
                                 bounds,
@@ -501,148 +645,6 @@ where
             _ => {}
         }
 
-        if let Some(scroller_grabbed_at) = state.y_scroller_grabbed_at {
-            match event {
-                Event::Mouse(mouse::Event::CursorMoved { .. })
-                | Event::Touch(touch::Event::FingerMoved { .. }) => {
-                    if let Some(scrollbar) = scrollbars.y {
-                        let Some(cursor_position) = cursor.position() else {
-                            return event::Status::Ignored;
-                        };
-
-                        state.scroll_y_to(
-                            scrollbar.scroll_percentage_y(
-                                scroller_grabbed_at,
-                                cursor_position,
-                            ),
-                            bounds,
-                            content_bounds,
-                        );
-
-                        notify_on_scroll(
-                            state,
-                            &self.on_scroll,
-                            bounds,
-                            content_bounds,
-                            shell,
-                        );
-
-                        event_status = event::Status::Captured;
-                    }
-                }
-                _ => {}
-            }
-        } else if mouse_over_y_scrollbar {
-            match event {
-                Event::Mouse(mouse::Event::ButtonPressed(
-                    mouse::Button::Left,
-                ))
-                | Event::Touch(touch::Event::FingerPressed { .. }) => {
-                    let Some(cursor_position) = cursor.position() else {
-                        return event::Status::Ignored;
-                    };
-
-                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
-                        scrollbars.grab_y_scroller(cursor_position),
-                        scrollbars.y,
-                    ) {
-                        state.scroll_y_to(
-                            scrollbar.scroll_percentage_y(
-                                scroller_grabbed_at,
-                                cursor_position,
-                            ),
-                            bounds,
-                            content_bounds,
-                        );
-
-                        state.y_scroller_grabbed_at = Some(scroller_grabbed_at);
-
-                        notify_on_scroll(
-                            state,
-                            &self.on_scroll,
-                            bounds,
-                            content_bounds,
-                            shell,
-                        );
-                    }
-
-                    event_status = event::Status::Captured;
-                }
-                _ => {}
-            }
-        }
-
-        if let Some(scroller_grabbed_at) = state.x_scroller_grabbed_at {
-            match event {
-                Event::Mouse(mouse::Event::CursorMoved { .. })
-                | Event::Touch(touch::Event::FingerMoved { .. }) => {
-                    let Some(cursor_position) = cursor.position() else {
-                        return event::Status::Ignored;
-                    };
-
-                    if let Some(scrollbar) = scrollbars.x {
-                        state.scroll_x_to(
-                            scrollbar.scroll_percentage_x(
-                                scroller_grabbed_at,
-                                cursor_position,
-                            ),
-                            bounds,
-                            content_bounds,
-                        );
-
-                        notify_on_scroll(
-                            state,
-                            &self.on_scroll,
-                            bounds,
-                            content_bounds,
-                            shell,
-                        );
-                    }
-
-                    event_status = event::Status::Captured;
-                }
-                _ => {}
-            }
-        } else if mouse_over_x_scrollbar {
-            match event {
-                Event::Mouse(mouse::Event::ButtonPressed(
-                    mouse::Button::Left,
-                ))
-                | Event::Touch(touch::Event::FingerPressed { .. }) => {
-                    let Some(cursor_position) = cursor.position() else {
-                        return event::Status::Ignored;
-                    };
-
-                    if let (Some(scroller_grabbed_at), Some(scrollbar)) = (
-                        scrollbars.grab_x_scroller(cursor_position),
-                        scrollbars.x,
-                    ) {
-                        state.scroll_x_to(
-                            scrollbar.scroll_percentage_x(
-                                scroller_grabbed_at,
-                                cursor_position,
-                            ),
-                            bounds,
-                            content_bounds,
-                        );
-
-                        state.x_scroller_grabbed_at = Some(scroller_grabbed_at);
-
-                        notify_on_scroll(
-                            state,
-                            &self.on_scroll,
-                            bounds,
-                            content_bounds,
-                            shell,
-                        );
-
-                        event_status = event::Status::Captured;
-                    }
-                }
-                _ => {}
-            }
-        }
-
         event_status
     }
 
@@ -651,10 +653,10 @@ where
         tree: &Tree,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
-        _viewport: &Rectangle,
+        viewport: &Rectangle,
     ) {
         let state = tree.state.downcast_ref::<State>();
 
@@ -662,6 +664,10 @@ where
         let content_layout = layout.children().next().unwrap();
         let content_bounds = content_layout.bounds();
 
+        let Some(visible_bounds) = bounds.intersection(viewport) else {
+            return;
+        };
+
         let scrollbars =
             Scrollbars::new(state, self.direction, bounds, content_bounds);
 
@@ -701,17 +707,13 @@ where
             Status::Active
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
-        container::draw_background(
-            renderer,
-            &appearance.container,
-            layout.bounds(),
-        );
+        container::draw_background(renderer, &style.container, layout.bounds());
 
         // Draw inner content
         if scrollbars.active() {
-            renderer.with_layer(bounds, |renderer| {
+            renderer.with_layer(visible_bounds, |renderer| {
                 renderer.with_translation(
                     Vector::new(-translation.x, -translation.y),
                     |renderer| {
@@ -719,7 +721,7 @@ where
                             &tree.children[0],
                             renderer,
                             theme,
-                            style,
+                            defaults,
                             content_layout,
                             cursor,
                             &Rectangle {
@@ -774,15 +776,15 @@ where
 
             renderer.with_layer(
                 Rectangle {
-                    width: bounds.width + 2.0,
-                    height: bounds.height + 2.0,
-                    ..bounds
+                    width: (visible_bounds.width + 2.0).min(viewport.width),
+                    height: (visible_bounds.height + 2.0).min(viewport.height),
+                    ..visible_bounds
                 },
                 |renderer| {
                     if let Some(scrollbar) = scrollbars.y {
                         draw_scrollbar(
                             renderer,
-                            appearance.vertical_scrollbar,
+                            style.vertical_scrollbar,
                             &scrollbar,
                         );
                     }
@@ -790,14 +792,14 @@ where
                     if let Some(scrollbar) = scrollbars.x {
                         draw_scrollbar(
                             renderer,
-                            appearance.horizontal_scrollbar,
+                            style.horizontal_scrollbar,
                             &scrollbar,
                         );
                     }
 
                     if let (Some(x), Some(y)) = (scrollbars.x, scrollbars.y) {
                         let background =
-                            appearance.gap.or(appearance.container.background);
+                            style.gap.or(style.container.background);
 
                         if let Some(background) = background {
                             renderer.fill_quad(
@@ -821,7 +823,7 @@ where
                 &tree.children[0],
                 renderer,
                 theme,
-                style,
+                defaults,
                 content_layout,
                 cursor,
                 &Rectangle {
@@ -857,7 +859,7 @@ where
         if (mouse_over_x_scrollbar || mouse_over_y_scrollbar)
             || state.scrollers_grabbed()
         {
-            mouse::Interaction::Idle
+            mouse::Interaction::None
         } else {
             let translation =
                 state.translation(self.direction, bounds, content_bounds);
@@ -916,8 +918,8 @@ impl<'a, Message, Theme, Renderer>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
-    Renderer: 'a + crate::core::Renderer,
+    Theme: 'a + Catalog,
+    Renderer: 'a + core::Renderer,
 {
     fn from(
         text_input: Scrollable<'a, Message, Theme, Renderer>,
@@ -968,51 +970,54 @@ pub fn scroll_to<Message: 'static>(
     Command::widget(operation::scrollable::scroll_to(id.0, offset))
 }
 
+/// Returns [`true`] if the viewport actually changed.
 fn notify_on_scroll<Message>(
     state: &mut State,
     on_scroll: &Option<Box<dyn Fn(Viewport) -> Message + '_>>,
     bounds: Rectangle,
     content_bounds: Rectangle,
     shell: &mut Shell<'_, Message>,
-) {
-    if let Some(on_scroll) = on_scroll {
-        if content_bounds.width <= bounds.width
-            && content_bounds.height <= bounds.height
-        {
-            return;
-        }
+) -> bool {
+    if content_bounds.width <= bounds.width
+        && content_bounds.height <= bounds.height
+    {
+        return false;
+    }
 
-        let viewport = Viewport {
-            offset_x: state.offset_x,
-            offset_y: state.offset_y,
-            bounds,
-            content_bounds,
-        };
+    let viewport = Viewport {
+        offset_x: state.offset_x,
+        offset_y: state.offset_y,
+        bounds,
+        content_bounds,
+    };
 
-        // Don't publish redundant viewports to shell
-        if let Some(last_notified) = state.last_notified {
-            let last_relative_offset = last_notified.relative_offset();
-            let current_relative_offset = viewport.relative_offset();
+    // Don't publish redundant viewports to shell
+    if let Some(last_notified) = state.last_notified {
+        let last_relative_offset = last_notified.relative_offset();
+        let current_relative_offset = viewport.relative_offset();
 
-            let last_absolute_offset = last_notified.absolute_offset();
-            let current_absolute_offset = viewport.absolute_offset();
+        let last_absolute_offset = last_notified.absolute_offset();
+        let current_absolute_offset = viewport.absolute_offset();
 
-            let unchanged = |a: f32, b: f32| {
-                (a - b).abs() <= f32::EPSILON || (a.is_nan() && b.is_nan())
-            };
+        let unchanged = |a: f32, b: f32| {
+            (a - b).abs() <= f32::EPSILON || (a.is_nan() && b.is_nan())
+        };
 
-            if unchanged(last_relative_offset.x, current_relative_offset.x)
-                && unchanged(last_relative_offset.y, current_relative_offset.y)
-                && unchanged(last_absolute_offset.x, current_absolute_offset.x)
-                && unchanged(last_absolute_offset.y, current_absolute_offset.y)
-            {
-                return;
-            }
+        if unchanged(last_relative_offset.x, current_relative_offset.x)
+            && unchanged(last_relative_offset.y, current_relative_offset.y)
+            && unchanged(last_absolute_offset.x, current_absolute_offset.x)
+            && unchanged(last_absolute_offset.y, current_absolute_offset.y)
+        {
+            return false;
         }
+    }
 
+    if let Some(on_scroll) = on_scroll {
         shell.publish(on_scroll(viewport));
-        state.last_notified = Some(viewport);
     }
+    state.last_notified = Some(viewport);
+
+    true
 }
 
 #[derive(Debug, Clone, Copy)]
@@ -1570,9 +1575,9 @@ pub enum Status {
 
 /// The appearance of a scrolable.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
-    /// The [`container::Appearance`] of a scrollable.
-    pub container: container::Appearance,
+pub struct Style {
+    /// The [`container::Style`] of a scrollable.
+    pub container: container::Style,
     /// The vertical [`Scrollbar`] appearance.
     pub vertical_scrollbar: Scrollbar,
     /// The horizontal [`Scrollbar`] appearance.
@@ -1601,29 +1606,35 @@ pub struct Scroller {
     pub border: Border,
 }
 
-/// The style of a [`Scrollable`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Scrollable`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Scrollable`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Scrollable`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`Scrollable`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`Scrollable`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     let scrollbar = Scrollbar {
@@ -1636,8 +1647,8 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
     };
 
     match status {
-        Status::Active => Appearance {
-            container: container::Appearance::default(),
+        Status::Active => Style {
+            container: container::Style::default(),
             vertical_scrollbar: scrollbar,
             horizontal_scrollbar: scrollbar,
             gap: None,
@@ -1654,8 +1665,8 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
                 ..scrollbar
             };
 
-            Appearance {
-                container: container::Appearance::default(),
+            Style {
+                container: container::Style::default(),
                 vertical_scrollbar: if is_vertical_scrollbar_hovered {
                     hovered_scrollbar
                 } else {
@@ -1681,8 +1692,8 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
                 ..scrollbar
             };
 
-            Appearance {
-                container: container::Appearance::default(),
+            Style {
+                container: container::Style::default(),
                 vertical_scrollbar: if is_vertical_scrollbar_dragged {
                     dragged_scrollbar
                 } else {
diff --git a/widget/src/shader.rs b/widget/src/shader.rs
index 68112f83..fad2f4eb 100644
--- a/widget/src/shader.rs
+++ b/widget/src/shader.rs
@@ -13,12 +13,13 @@ use crate::core::widget::tree::{self, Tree};
 use crate::core::widget::{self, Widget};
 use crate::core::window;
 use crate::core::{Clipboard, Element, Length, Rectangle, Shell, Size};
-use crate::renderer::wgpu::primitive::pipeline;
+use crate::renderer::wgpu::primitive;
 
 use std::marker::PhantomData;
 
+pub use crate::graphics::Viewport;
 pub use crate::renderer::wgpu::wgpu;
-pub use pipeline::{Primitive, Storage};
+pub use primitive::{Primitive, Storage};
 
 /// A widget which can render custom shaders with Iced's `wgpu` backend.
 ///
@@ -60,7 +61,7 @@ impl<P, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Shader<Message, P>
 where
     P: Program<Message>,
-    Renderer: pipeline::Renderer,
+    Renderer: primitive::Renderer,
 {
     fn tag(&self) -> tree::Tag {
         struct Tag<T>(T);
@@ -160,7 +161,7 @@ where
         let bounds = layout.bounds();
         let state = tree.state.downcast_ref::<P::State>();
 
-        renderer.draw_pipeline_primitive(
+        renderer.draw_primitive(
             bounds,
             self.program.draw(state, cursor_position, bounds),
         );
@@ -171,7 +172,7 @@ impl<'a, Message, Theme, Renderer, P> From<Shader<Message, P>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Renderer: pipeline::Renderer,
+    Renderer: primitive::Renderer,
     P: Program<Message> + 'a,
 {
     fn from(
diff --git a/widget/src/shader/program.rs b/widget/src/shader/program.rs
index 6dd50404..902c7c3b 100644
--- a/widget/src/shader/program.rs
+++ b/widget/src/shader/program.rs
@@ -1,7 +1,7 @@
 use crate::core::event;
 use crate::core::mouse;
 use crate::core::{Rectangle, Shell};
-use crate::renderer::wgpu::primitive::pipeline;
+use crate::renderer::wgpu::Primitive;
 use crate::shader;
 
 /// The state and logic of a [`Shader`] widget.
@@ -15,7 +15,7 @@ pub trait Program<Message> {
     type State: Default + 'static;
 
     /// The type of primitive this [`Program`] can draw.
-    type Primitive: pipeline::Primitive + 'static;
+    type Primitive: Primitive + 'static;
 
     /// Update the internal [`State`] of the [`Program`]. This can be used to reflect state changes
     /// based on mouse & other events. You can use the [`Shell`] to publish messages, request a
diff --git a/widget/src/slider.rs b/widget/src/slider.rs
index d3b46a98..a8f1d192 100644
--- a/widget/src/slider.rs
+++ b/widget/src/slider.rs
@@ -9,7 +9,7 @@ use crate::core::renderer;
 use crate::core::touch;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Border, Clipboard, Color, Element, Layout, Length, Pixels, Point,
+    self, Border, Clipboard, Color, Element, Layout, Length, Pixels, Point,
     Rectangle, Shell, Size, Theme, Widget,
 };
 
@@ -39,7 +39,10 @@ use std::ops::RangeInclusive;
 ///
 /// ![Slider drawn by Coffee's renderer](https://github.com/hecrj/coffee/blob/bda9818f823dfcb8a7ad0ff4940b4d4b387b5208/images/ui/slider.png?raw=true)
 #[allow(missing_debug_implementations)]
-pub struct Slider<'a, T, Message, Theme = crate::Theme> {
+pub struct Slider<'a, T, Message, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     range: RangeInclusive<T>,
     step: T,
     shift_step: Option<T>,
@@ -49,13 +52,14 @@ pub struct Slider<'a, T, Message, Theme = crate::Theme> {
     on_release: Option<Message>,
     width: Length,
     height: f32,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, T, Message, Theme> Slider<'a, T, Message, Theme>
 where
     T: Copy + From<u8> + PartialOrd,
     Message: Clone,
+    Theme: Catalog,
 {
     /// The default height of a [`Slider`].
     pub const DEFAULT_HEIGHT: f32 = 16.0;
@@ -70,7 +74,6 @@ where
     ///   `Message`.
     pub fn new<F>(range: RangeInclusive<T>, value: T, on_change: F) -> Self
     where
-        Theme: DefaultStyle + 'a,
         F: 'a + Fn(T) -> Message,
     {
         let value = if value >= *range.start() {
@@ -95,7 +98,7 @@ where
             on_release: None,
             width: Length::Fill,
             height: Self::DEFAULT_HEIGHT,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -130,15 +133,6 @@ where
         self
     }
 
-    /// Sets the style of the [`Slider`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
-        self
-    }
-
     /// Sets the step size of the [`Slider`].
     pub fn step(mut self, step: impl Into<T>) -> Self {
         self.step = step.into();
@@ -152,6 +146,24 @@ where
         self.shift_step = Some(shift_step.into());
         self
     }
+
+    /// Sets the style of the [`Slider`].
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Slider`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
 }
 
 impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
@@ -159,7 +171,8 @@ impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
 where
     T: Copy + Into<f64> + num_traits::FromPrimitive,
     Message: Clone,
-    Renderer: crate::core::Renderer,
+    Theme: Catalog,
+    Renderer: core::Renderer,
 {
     fn tag(&self) -> tree::Tag {
         tree::Tag::of::<State>()
@@ -349,8 +362,8 @@ where
         let bounds = layout.bounds();
         let is_mouse_over = cursor.is_over(bounds);
 
-        let style = (self.style)(
-            theme,
+        let style = theme.style(
+            &self.class,
             if state.is_dragging {
                 Status::Dragged
             } else if is_mouse_over {
@@ -461,8 +474,8 @@ impl<'a, T, Message, Theme, Renderer> From<Slider<'a, T, Message, Theme>>
 where
     T: Copy + Into<f64> + num_traits::FromPrimitive + 'a,
     Message: Clone + 'a,
-    Theme: 'a,
-    Renderer: crate::core::Renderer + 'a,
+    Theme: Catalog + 'a,
+    Renderer: core::Renderer + 'a,
 {
     fn from(
         slider: Slider<'a, T, Message, Theme>,
@@ -490,15 +503,15 @@ pub enum Status {
 
 /// The appearance of a slider.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The colors of the rail of the slider.
     pub rail: Rail,
     /// The appearance of the [`Handle`] of the slider.
     pub handle: Handle,
 }
 
-impl Appearance {
-    /// Changes the [`HandleShape`] of the [`Appearance`] to a circle
+impl Style {
+    /// Changes the [`HandleShape`] of the [`Style`] to a circle
     /// with the given radius.
     pub fn with_circular_handle(mut self, radius: impl Into<Pixels>) -> Self {
         self.handle.shape = HandleShape::Circle {
@@ -549,29 +562,35 @@ pub enum HandleShape {
     },
 }
 
-/// The style of a [`Slider`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Slider`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Slider`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Slider`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`Slider`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`Slider`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     let color = match status {
@@ -580,7 +599,7 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
         Status::Dragged => palette.primary.strong.color,
     };
 
-    Appearance {
+    Style {
         rail: Rail {
             colors: (color, palette.secondary.base.color),
             width: 4.0,
diff --git a/widget/src/stack.rs b/widget/src/stack.rs
new file mode 100644
index 00000000..5035541b
--- /dev/null
+++ b/widget/src/stack.rs
@@ -0,0 +1,333 @@
+//! Display content on top of other content.
+use crate::core::event::{self, Event};
+use crate::core::layout;
+use crate::core::mouse;
+use crate::core::overlay;
+use crate::core::renderer;
+use crate::core::widget::{Operation, Tree};
+use crate::core::{
+    Clipboard, Element, Layout, Length, Rectangle, Shell, Size, Vector, Widget,
+};
+
+/// A container that displays children on top of each other.
+///
+/// The first [`Element`] dictates the intrinsic [`Size`] of a [`Stack`] and
+/// will be displayed as the base layer. Every consecutive [`Element`] will be
+/// renderer on top; on its own layer.
+///
+/// Keep in mind that too much layering will normally produce bad UX as well as
+/// introduce certain rendering overhead. Use this widget sparingly!
+#[allow(missing_debug_implementations)]
+pub struct Stack<'a, Message, Theme = crate::Theme, Renderer = crate::Renderer>
+{
+    width: Length,
+    height: Length,
+    children: Vec<Element<'a, Message, Theme, Renderer>>,
+}
+
+impl<'a, Message, Theme, Renderer> Stack<'a, Message, Theme, Renderer>
+where
+    Renderer: crate::core::Renderer,
+{
+    /// Creates an empty [`Stack`].
+    pub fn new() -> Self {
+        Self::from_vec(Vec::new())
+    }
+
+    /// Creates a [`Stack`] with the given capacity.
+    pub fn with_capacity(capacity: usize) -> Self {
+        Self::from_vec(Vec::with_capacity(capacity))
+    }
+
+    /// Creates a [`Stack`] with the given elements.
+    pub fn with_children(
+        children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
+    ) -> Self {
+        let iterator = children.into_iter();
+
+        Self::with_capacity(iterator.size_hint().0).extend(iterator)
+    }
+
+    /// Creates a [`Stack`] from an already allocated [`Vec`].
+    ///
+    /// Keep in mind that the [`Stack`] will not inspect the [`Vec`], which means
+    /// it won't automatically adapt to the sizing strategy of its contents.
+    ///
+    /// If any of the children have a [`Length::Fill`] strategy, you will need to
+    /// call [`Stack::width`] or [`Stack::height`] accordingly.
+    pub fn from_vec(
+        children: Vec<Element<'a, Message, Theme, Renderer>>,
+    ) -> Self {
+        Self {
+            width: Length::Shrink,
+            height: Length::Shrink,
+            children,
+        }
+    }
+
+    /// Sets the width of the [`Stack`].
+    pub fn width(mut self, width: impl Into<Length>) -> Self {
+        self.width = width.into();
+        self
+    }
+
+    /// Sets the height of the [`Stack`].
+    pub fn height(mut self, height: impl Into<Length>) -> Self {
+        self.height = height.into();
+        self
+    }
+
+    /// Adds an element to the [`Stack`].
+    pub fn push(
+        mut self,
+        child: impl Into<Element<'a, Message, Theme, Renderer>>,
+    ) -> Self {
+        let child = child.into();
+
+        if self.children.is_empty() {
+            let child_size = child.as_widget().size_hint();
+
+            self.width = self.width.enclose(child_size.width);
+            self.height = self.height.enclose(child_size.height);
+        }
+
+        self.children.push(child);
+        self
+    }
+
+    /// Adds an element to the [`Stack`], if `Some`.
+    pub fn push_maybe(
+        self,
+        child: Option<impl Into<Element<'a, Message, Theme, Renderer>>>,
+    ) -> Self {
+        if let Some(child) = child {
+            self.push(child)
+        } else {
+            self
+        }
+    }
+
+    /// Extends the [`Stack`] with the given children.
+    pub fn extend(
+        self,
+        children: impl IntoIterator<Item = Element<'a, Message, Theme, Renderer>>,
+    ) -> Self {
+        children.into_iter().fold(self, Self::push)
+    }
+}
+
+impl<'a, Message, Renderer> Default for Stack<'a, Message, Renderer>
+where
+    Renderer: crate::core::Renderer,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
+    for Stack<'a, Message, Theme, Renderer>
+where
+    Renderer: crate::core::Renderer,
+{
+    fn children(&self) -> Vec<Tree> {
+        self.children.iter().map(Tree::new).collect()
+    }
+
+    fn diff(&self, tree: &mut Tree) {
+        tree.diff_children(&self.children);
+    }
+
+    fn size(&self) -> Size<Length> {
+        Size {
+            width: self.width,
+            height: self.height,
+        }
+    }
+
+    fn layout(
+        &self,
+        tree: &mut Tree,
+        renderer: &Renderer,
+        limits: &layout::Limits,
+    ) -> layout::Node {
+        let limits = limits.width(self.width).height(self.height);
+
+        if self.children.is_empty() {
+            return layout::Node::new(limits.resolve(
+                self.width,
+                self.height,
+                Size::ZERO,
+            ));
+        }
+
+        let base = self.children[0].as_widget().layout(
+            &mut tree.children[0],
+            renderer,
+            &limits,
+        );
+
+        let size = limits.resolve(self.width, self.height, base.size());
+        let limits = layout::Limits::new(Size::ZERO, size);
+
+        let nodes = std::iter::once(base)
+            .chain(self.children[1..].iter().zip(&mut tree.children[1..]).map(
+                |(layer, tree)| {
+                    let node =
+                        layer.as_widget().layout(tree, renderer, &limits);
+
+                    node
+                },
+            ))
+            .collect();
+
+        layout::Node::with_children(size, nodes)
+    }
+
+    fn operate(
+        &self,
+        tree: &mut Tree,
+        layout: Layout<'_>,
+        renderer: &Renderer,
+        operation: &mut dyn Operation<Message>,
+    ) {
+        operation.container(None, layout.bounds(), &mut |operation| {
+            self.children
+                .iter()
+                .zip(&mut tree.children)
+                .zip(layout.children())
+                .for_each(|((child, state), layout)| {
+                    child
+                        .as_widget()
+                        .operate(state, layout, renderer, operation);
+                });
+        });
+    }
+
+    fn on_event(
+        &mut self,
+        tree: &mut Tree,
+        event: Event,
+        layout: Layout<'_>,
+        cursor: mouse::Cursor,
+        renderer: &Renderer,
+        clipboard: &mut dyn Clipboard,
+        shell: &mut Shell<'_, Message>,
+        viewport: &Rectangle,
+    ) -> event::Status {
+        self.children
+            .iter_mut()
+            .rev()
+            .zip(tree.children.iter_mut().rev())
+            .zip(layout.children().rev())
+            .map(|((child, state), layout)| {
+                child.as_widget_mut().on_event(
+                    state,
+                    event.clone(),
+                    layout,
+                    cursor,
+                    renderer,
+                    clipboard,
+                    shell,
+                    viewport,
+                )
+            })
+            .find(|&status| status == event::Status::Captured)
+            .unwrap_or(event::Status::Ignored)
+    }
+
+    fn mouse_interaction(
+        &self,
+        tree: &Tree,
+        layout: Layout<'_>,
+        cursor: mouse::Cursor,
+        viewport: &Rectangle,
+        renderer: &Renderer,
+    ) -> mouse::Interaction {
+        self.children
+            .iter()
+            .rev()
+            .zip(tree.children.iter().rev())
+            .zip(layout.children().rev())
+            .map(|((child, state), layout)| {
+                child.as_widget().mouse_interaction(
+                    state, layout, cursor, viewport, renderer,
+                )
+            })
+            .find(|&interaction| interaction != mouse::Interaction::None)
+            .unwrap_or_default()
+    }
+
+    fn draw(
+        &self,
+        tree: &Tree,
+        renderer: &mut Renderer,
+        theme: &Theme,
+        style: &renderer::Style,
+        layout: Layout<'_>,
+        cursor: mouse::Cursor,
+        viewport: &Rectangle,
+    ) {
+        if let Some(clipped_viewport) = layout.bounds().intersection(viewport) {
+            for (i, ((layer, state), layout)) in self
+                .children
+                .iter()
+                .zip(&tree.children)
+                .zip(layout.children())
+                .enumerate()
+            {
+                if i > 0 {
+                    renderer.with_layer(clipped_viewport, |renderer| {
+                        layer.as_widget().draw(
+                            state,
+                            renderer,
+                            theme,
+                            style,
+                            layout,
+                            cursor,
+                            &clipped_viewport,
+                        );
+                    });
+                } else {
+                    layer.as_widget().draw(
+                        state,
+                        renderer,
+                        theme,
+                        style,
+                        layout,
+                        cursor,
+                        &clipped_viewport,
+                    );
+                }
+            }
+        }
+    }
+
+    fn overlay<'b>(
+        &'b mut self,
+        tree: &'b mut Tree,
+        layout: Layout<'_>,
+        renderer: &Renderer,
+        translation: Vector,
+    ) -> Option<overlay::Element<'b, Message, Theme, Renderer>> {
+        overlay::from_children(
+            &mut self.children,
+            tree,
+            layout,
+            renderer,
+            translation,
+        )
+    }
+}
+
+impl<'a, Message, Theme, Renderer> From<Stack<'a, Message, Theme, Renderer>>
+    for Element<'a, Message, Theme, Renderer>
+where
+    Message: 'a,
+    Theme: 'a,
+    Renderer: crate::core::Renderer + 'a,
+{
+    fn from(stack: Stack<'a, Message, Theme, Renderer>) -> Self {
+        Self::new(stack)
+    }
+}
diff --git a/widget/src/svg.rs b/widget/src/svg.rs
index 1ac07ade..4551bcad 100644
--- a/widget/src/svg.rs
+++ b/widget/src/svg.rs
@@ -5,8 +5,8 @@ use crate::core::renderer;
 use crate::core::svg;
 use crate::core::widget::Tree;
 use crate::core::{
-    Color, ContentFit, Element, Layout, Length, Rectangle, Size, Theme, Vector,
-    Widget,
+    Color, ContentFit, Element, Layout, Length, Point, Rectangle, Rotation,
+    Size, Theme, Vector, Widget,
 };
 
 use std::path::PathBuf;
@@ -20,36 +20,40 @@ pub use crate::core::svg::Handle;
 /// [`Svg`] images can have a considerable rendering cost when resized,
 /// specially when they are complex.
 #[allow(missing_debug_implementations)]
-pub struct Svg<'a, Theme = crate::Theme> {
+pub struct Svg<'a, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     handle: Handle,
     width: Length,
     height: Length,
     content_fit: ContentFit,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
+    rotation: Rotation,
+    opacity: f32,
 }
 
-impl<'a, Theme> Svg<'a, Theme> {
+impl<'a, Theme> Svg<'a, Theme>
+where
+    Theme: Catalog,
+{
     /// Creates a new [`Svg`] from the given [`Handle`].
-    pub fn new(handle: impl Into<Handle>) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn new(handle: impl Into<Handle>) -> Self {
         Svg {
             handle: handle.into(),
             width: Length::Fill,
             height: Length::Shrink,
             content_fit: ContentFit::Contain,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
+            rotation: Rotation::default(),
+            opacity: 1.0,
         }
     }
 
     /// Creates a new [`Svg`] that will display the contents of the file at the
     /// provided path.
     #[must_use]
-    pub fn from_path(path: impl Into<PathBuf>) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn from_path(path: impl Into<PathBuf>) -> Self {
         Self::new(Handle::from_path(path))
     }
 
@@ -78,13 +82,36 @@ impl<'a, Theme> Svg<'a, Theme> {
         }
     }
 
-    /// Sets the style variant of this [`Svg`].
+    /// Sets the style of the [`Svg`].
     #[must_use]
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Svg`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
+
+    /// Applies the given [`Rotation`] to the [`Svg`].
+    pub fn rotation(mut self, rotation: impl Into<Rotation>) -> Self {
+        self.rotation = rotation.into();
+        self
+    }
+
+    /// Sets the opacity of the [`Svg`].
+    ///
+    /// It should be in the [0.0, 1.0] range—`0.0` meaning completely transparent,
+    /// and `1.0` meaning completely opaque.
+    pub fn opacity(mut self, opacity: impl Into<f32>) -> Self {
+        self.opacity = opacity.into();
         self
     }
 }
@@ -93,6 +120,7 @@ impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Svg<'a, Theme>
 where
     Renderer: svg::Renderer,
+    Theme: Catalog,
 {
     fn size(&self) -> Size<Length> {
         Size {
@@ -108,14 +136,17 @@ where
         limits: &layout::Limits,
     ) -> layout::Node {
         // The raw w/h of the underlying image
-        let Size { width, height } = renderer.dimensions(&self.handle);
+        let Size { width, height } = renderer.measure_svg(&self.handle);
         let image_size = Size::new(width as f32, height as f32);
 
+        // The rotated size of the svg
+        let rotated_size = self.rotation.apply(image_size);
+
         // The size to be available to the widget prior to `Shrink`ing
-        let raw_size = limits.resolve(self.width, self.height, image_size);
+        let raw_size = limits.resolve(self.width, self.height, rotated_size);
 
         // The uncropped size of the image when fit to the bounds above
-        let full_size = self.content_fit.fit(image_size, raw_size);
+        let full_size = self.content_fit.fit(rotated_size, raw_size);
 
         // Shrink the widget to fit the resized image, if requested
         let final_size = Size {
@@ -142,37 +173,49 @@ where
         cursor: mouse::Cursor,
         _viewport: &Rectangle,
     ) {
-        let Size { width, height } = renderer.dimensions(&self.handle);
+        let Size { width, height } = renderer.measure_svg(&self.handle);
         let image_size = Size::new(width as f32, height as f32);
+        let rotated_size = self.rotation.apply(image_size);
 
         let bounds = layout.bounds();
-        let adjusted_fit = self.content_fit.fit(image_size, bounds.size());
-        let is_mouse_over = cursor.is_over(bounds);
+        let adjusted_fit = self.content_fit.fit(rotated_size, bounds.size());
+        let scale = Vector::new(
+            adjusted_fit.width / rotated_size.width,
+            adjusted_fit.height / rotated_size.height,
+        );
 
-        let render = |renderer: &mut Renderer| {
-            let offset = Vector::new(
-                (bounds.width - adjusted_fit.width).max(0.0) / 2.0,
-                (bounds.height - adjusted_fit.height).max(0.0) / 2.0,
-            );
+        let final_size = image_size * scale;
 
-            let drawing_bounds = Rectangle {
-                width: adjusted_fit.width,
-                height: adjusted_fit.height,
-                ..bounds
-            };
+        let position = match self.content_fit {
+            ContentFit::None => Point::new(
+                bounds.x + (rotated_size.width - adjusted_fit.width) / 2.0,
+                bounds.y + (rotated_size.height - adjusted_fit.height) / 2.0,
+            ),
+            _ => Point::new(
+                bounds.center_x() - final_size.width / 2.0,
+                bounds.center_y() - final_size.height / 2.0,
+            ),
+        };
 
-            let status = if is_mouse_over {
-                Status::Hovered
-            } else {
-                Status::Idle
-            };
+        let drawing_bounds = Rectangle::new(position, final_size);
 
-            let appearance = (self.style)(theme, status);
+        let is_mouse_over = cursor.is_over(bounds);
 
-            renderer.draw(
+        let status = if is_mouse_over {
+            Status::Hovered
+        } else {
+            Status::Idle
+        };
+
+        let style = theme.style(&self.class, status);
+
+        let render = |renderer: &mut Renderer| {
+            renderer.draw_svg(
                 self.handle.clone(),
-                appearance.color,
-                drawing_bounds + offset,
+                style.color,
+                drawing_bounds,
+                self.rotation.radians(),
+                self.opacity,
             );
         };
 
@@ -189,7 +232,7 @@ where
 impl<'a, Message, Theme, Renderer> From<Svg<'a, Theme>>
     for Element<'a, Message, Theme, Renderer>
 where
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: svg::Renderer + 'a,
 {
     fn from(icon: Svg<'a, Theme>) -> Element<'a, Message, Theme, Renderer> {
@@ -208,7 +251,7 @@ pub enum Status {
 
 /// The appearance of an [`Svg`].
 #[derive(Debug, Clone, Copy, PartialEq, Default)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Color`] filter of an [`Svg`].
     ///
     /// Useful for coloring a symbolic icon.
@@ -217,23 +260,37 @@ pub struct Appearance {
     pub color: Option<Color>,
 }
 
-/// The style of an [`Svg`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of an [`Svg`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of an [`Svg`].
-pub trait DefaultStyle {
-    /// Returns the default style of an [`Svg`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, _status: Status) -> Appearance {
-        Appearance::default()
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(|_theme, _status| Style::default())
+    }
+
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+/// A styling function for an [`Svg`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl<'a, Theme> From<Style> for StyleFn<'a, Theme> {
+    fn from(style: Style) -> Self {
+        Box::new(move |_theme, _status| style)
     }
 }
diff --git a/widget/src/text_editor.rs b/widget/src/text_editor.rs
index 5b8f6a1b..7c0b98ea 100644
--- a/widget/src/text_editor.rs
+++ b/widget/src/text_editor.rs
@@ -32,6 +32,7 @@ pub struct TextEditor<
     Renderer = crate::Renderer,
 > where
     Highlighter: text::Highlighter,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     content: &'a Content<Renderer>,
@@ -41,7 +42,7 @@ pub struct TextEditor<
     width: Length,
     height: Length,
     padding: Padding,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
     on_edit: Option<Box<dyn Fn(Action) -> Message + 'a>>,
     highlighter_settings: Highlighter::Settings,
     highlighter_format: fn(
@@ -53,13 +54,11 @@ pub struct TextEditor<
 impl<'a, Message, Theme, Renderer>
     TextEditor<'a, highlighter::PlainText, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// Creates new [`TextEditor`] with the given [`Content`].
-    pub fn new(content: &'a Content<Renderer>) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
+    pub fn new(content: &'a Content<Renderer>) -> Self {
         Self {
             content,
             font: None,
@@ -68,7 +67,7 @@ where
             width: Length::Fill,
             height: Length::Shrink,
             padding: Padding::new(5.0),
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
             on_edit: None,
             highlighter_settings: (),
             highlighter_format: |_highlight, _theme| {
@@ -82,6 +81,7 @@ impl<'a, Highlighter, Message, Theme, Renderer>
     TextEditor<'a, Highlighter, Message, Theme, Renderer>
 where
     Highlighter: text::Highlighter,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// Sets the height of the [`TextEditor`].
@@ -110,6 +110,21 @@ where
         self
     }
 
+    /// Sets the text size of the [`TextEditor`].
+    pub fn size(mut self, size: impl Into<Pixels>) -> Self {
+        self.text_size = Some(size.into());
+        self
+    }
+
+    /// Sets the [`text::LineHeight`] of the [`TextEditor`].
+    pub fn line_height(
+        mut self,
+        line_height: impl Into<text::LineHeight>,
+    ) -> Self {
+        self.line_height = line_height.into();
+        self
+    }
+
     /// Sets the [`Padding`] of the [`TextEditor`].
     pub fn padding(mut self, padding: impl Into<Padding>) -> Self {
         self.padding = padding.into();
@@ -134,7 +149,7 @@ where
             width: self.width,
             height: self.height,
             padding: self.padding,
-            style: self.style,
+            class: self.class,
             on_edit: self.on_edit,
             highlighter_settings: settings,
             highlighter_format: to_format,
@@ -142,11 +157,20 @@ where
     }
 
     /// Sets the style of the [`TextEditor`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`TextEditor`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -295,7 +319,9 @@ where
     }
 }
 
-struct State<Highlighter: text::Highlighter> {
+/// The state of a [`TextEditor`].
+#[derive(Debug)]
+pub struct State<Highlighter: text::Highlighter> {
     is_focused: bool,
     last_click: Option<mouse::Click>,
     drag_click: Option<mouse::click::Kind>,
@@ -305,10 +331,18 @@ struct State<Highlighter: text::Highlighter> {
     highlighter_format_address: usize,
 }
 
+impl<Highlighter: text::Highlighter> State<Highlighter> {
+    /// Returns whether the [`TextEditor`] is currently focused or not.
+    pub fn is_focused(&self) -> bool {
+        self.is_focused
+    }
+}
+
 impl<'a, Highlighter, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for TextEditor<'a, Highlighter, Message, Theme, Renderer>
 where
     Highlighter: text::Highlighter,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn tag(&self) -> widget::tree::Tag {
@@ -479,7 +513,7 @@ where
         tree: &widget::Tree,
         renderer: &mut Renderer,
         theme: &Theme,
-        style: &renderer::Style,
+        defaults: &renderer::Style,
         layout: Layout<'_>,
         cursor: mouse::Cursor,
         viewport: &Rectangle,
@@ -508,22 +542,22 @@ where
             Status::Active
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: appearance.border,
+                border: style.border,
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
         renderer.fill_editor(
             &internal.editor,
             bounds.position()
                 + Vector::new(self.padding.left, self.padding.top),
-            style.text_color,
+            defaults.text_color,
             *viewport,
         );
 
@@ -535,27 +569,31 @@ where
         if state.is_focused {
             match internal.editor.cursor() {
                 Cursor::Caret(position) => {
-                    let position = position + translation;
+                    let cursor =
+                        Rectangle::new(
+                            position + translation,
+                            Size::new(
+                                1.0,
+                                self.line_height
+                                    .to_absolute(self.text_size.unwrap_or_else(
+                                        || renderer.default_size(),
+                                    ))
+                                    .into(),
+                            ),
+                        );
 
-                    if bounds.contains(position) {
+                    if let Some(clipped_cursor) = bounds.intersection(&cursor) {
                         renderer.fill_quad(
                             renderer::Quad {
                                 bounds: Rectangle {
-                                    x: position.x.floor(),
-                                    y: position.y,
-                                    width: 1.0,
-                                    height: self
-                                        .line_height
-                                        .to_absolute(
-                                            self.text_size.unwrap_or_else(
-                                                || renderer.default_size(),
-                                            ),
-                                        )
-                                        .into(),
+                                    x: clipped_cursor.x.floor(),
+                                    y: clipped_cursor.y,
+                                    width: clipped_cursor.width,
+                                    height: clipped_cursor.height,
                                 },
                                 ..renderer::Quad::default()
                             },
-                            appearance.value,
+                            style.value,
                         );
                     }
                 }
@@ -568,7 +606,7 @@ where
                                 bounds: range,
                                 ..renderer::Quad::default()
                             },
-                            appearance.selection,
+                            style.selection,
                         );
                     }
                 }
@@ -604,7 +642,7 @@ impl<'a, Highlighter, Message, Theme, Renderer>
 where
     Highlighter: text::Highlighter,
     Message: 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer,
 {
     fn from(
@@ -796,7 +834,7 @@ pub enum Status {
 
 /// The appearance of a text input.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the text input.
     pub background: Background,
     /// The [`Border`] of the text input.
@@ -811,32 +849,38 @@ pub struct Appearance {
     pub selection: Color,
 }
 
-/// The style of a [`TextEditor`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`TextEditor`].
+pub trait Catalog {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`TextEditor`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`TextEditor`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`TextEditor`].
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`TextEditor`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
-    let active = Appearance {
+    let active = Style {
         background: Background::Color(palette.background.base.color),
         border: Border {
             radius: 2.0.into(),
@@ -851,21 +895,21 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
 
     match status {
         Status::Active => active,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             border: Border {
                 color: palette.background.base.text,
                 ..active.border
             },
             ..active
         },
-        Status::Focused => Appearance {
+        Status::Focused => Style {
             border: Border {
                 color: palette.primary.strong.color,
                 ..active.border
             },
             ..active
         },
-        Status::Disabled => Appearance {
+        Status::Disabled => Style {
             background: Background::Color(palette.background.weak.color),
             value: active.placeholder,
             ..active
diff --git a/widget/src/text_input.rs b/widget/src/text_input.rs
index b161ec74..e9f07838 100644
--- a/widget/src/text_input.rs
+++ b/widget/src/text_input.rs
@@ -60,6 +60,7 @@ pub struct TextInput<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     id: Option<Id>,
@@ -75,7 +76,7 @@ pub struct TextInput<
     on_paste: Option<Box<dyn Fn(String) -> Message + 'a>>,
     on_submit: Option<Message>,
     icon: Option<Icon<Renderer::Font>>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 /// The default [`Padding`] of a [`TextInput`].
@@ -84,24 +85,12 @@ pub const DEFAULT_PADDING: Padding = Padding::new(5.0);
 impl<'a, Message, Theme, Renderer> TextInput<'a, Message, Theme, Renderer>
 where
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// Creates a new [`TextInput`] with the given placeholder and
     /// its current value.
-    pub fn new(placeholder: &str, value: &str) -> Self
-    where
-        Theme: DefaultStyle + 'a,
-    {
-        Self::with_style(placeholder, value, Theme::default_style)
-    }
-
-    /// Creates a new [`TextInput`] with the given placeholder,
-    /// its current value, and its style.
-    pub fn with_style(
-        placeholder: &str,
-        value: &str,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
+    pub fn new(placeholder: &str, value: &str) -> Self {
         TextInput {
             id: None,
             placeholder: String::from(placeholder),
@@ -116,7 +105,7 @@ where
             on_paste: None,
             on_submit: None,
             icon: None,
-            style: Box::new(style),
+            class: Theme::default(),
         }
     }
 
@@ -203,11 +192,19 @@ where
     }
 
     /// Sets the style of the [`TextInput`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`TextInput`].
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 
@@ -235,7 +232,7 @@ where
         let placeholder_text = Text {
             font,
             line_height: self.line_height,
-            content: &self.placeholder,
+            content: self.placeholder.as_str(),
             bounds: Size::new(f32::INFINITY, text_bounds.height),
             size: text_size,
             horizontal_alignment: alignment::Horizontal::Left,
@@ -254,9 +251,11 @@ where
         });
 
         if let Some(icon) = &self.icon {
+            let mut content = [0; 4];
+
             let icon_text = Text {
                 line_height: self.line_height,
-                content: &icon.code_point.to_string(),
+                content: icon.code_point.encode_utf8(&mut content) as &_,
                 font: icon.font,
                 size: icon.size.unwrap_or_else(|| renderer.default_size()),
                 bounds: Size::new(f32::INFINITY, text_bounds.height),
@@ -345,15 +344,15 @@ where
             Status::Active
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
         renderer.fill_quad(
             renderer::Quad {
                 bounds,
-                border: appearance.border,
+                border: style.border,
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
         if self.icon.is_some() {
@@ -362,14 +361,14 @@ where
             renderer.fill_paragraph(
                 &state.icon,
                 icon_layout.bounds().center(),
-                appearance.icon,
+                style.icon,
                 *viewport,
             );
         }
 
         let text = value.to_string();
 
-        let (cursor, offset) = if let Some(focus) = state
+        let (cursor, offset, is_selecting) = if let Some(focus) = state
             .is_focused
             .as_ref()
             .filter(|focus| focus.is_window_focused)
@@ -401,13 +400,13 @@ where
                                 },
                                 ..renderer::Quad::default()
                             },
-                            appearance.value,
+                            style.value,
                         ))
                     } else {
                         None
                     };
 
-                    (cursor, offset)
+                    (cursor, offset, false)
                 }
                 cursor::State::Selection { start, end } => {
                     let left = start.min(end);
@@ -440,18 +439,19 @@ where
                                 },
                                 ..renderer::Quad::default()
                             },
-                            appearance.selection,
+                            style.selection,
                         )),
                         if end == right {
                             right_offset
                         } else {
                             left_offset
                         },
+                        true,
                     )
                 }
             }
         } else {
-            (None, 0.0)
+            (None, 0.0, false)
         };
 
         let draw = |renderer: &mut Renderer, viewport| {
@@ -475,15 +475,15 @@ where
                 Point::new(text_bounds.x, text_bounds.center_y())
                     - Vector::new(offset, 0.0),
                 if text.is_empty() {
-                    appearance.placeholder
+                    style.placeholder
                 } else {
-                    appearance.value
+                    style.value
                 },
                 viewport,
             );
         };
 
-        if cursor.is_some() {
+        if is_selecting {
             renderer
                 .with_layer(text_bounds, |renderer| draw(renderer, *viewport));
         } else {
@@ -496,6 +496,7 @@ impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for TextInput<'a, Message, Theme, Renderer>
 where
     Message: Clone,
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn tag(&self) -> tree::Tag {
@@ -712,7 +713,8 @@ where
 
                     match key.as_ref() {
                         keyboard::Key::Character("c")
-                            if state.keyboard_modifiers.command() =>
+                            if state.keyboard_modifiers.command()
+                                && !self.is_secure =>
                         {
                             if let Some((start, end)) =
                                 state.cursor.selection(&self.value)
@@ -726,7 +728,8 @@ where
                             return event::Status::Captured;
                         }
                         keyboard::Key::Character("x")
-                            if state.keyboard_modifiers.command() =>
+                            if state.keyboard_modifiers.command()
+                                && !self.is_secure =>
                         {
                             if let Some((start, end)) =
                                 state.cursor.selection(&self.value)
@@ -1058,8 +1061,8 @@ where
 impl<'a, Message, Theme, Renderer> From<TextInput<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
-    Message: 'a + Clone,
-    Theme: 'a,
+    Message: Clone + 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(
@@ -1400,7 +1403,7 @@ pub enum Status {
 
 /// The appearance of a text input.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The [`Background`] of the text input.
     pub background: Background,
     /// The [`Border`] of the text input.
@@ -1415,32 +1418,40 @@ pub struct Appearance {
     pub selection: Color,
 }
 
-/// The style of a [`TextInput`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`TextInput`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`TextInput`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`TextInput`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`TextInput`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`TextInput`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
-    let active = Appearance {
+    let active = Style {
         background: Background::Color(palette.background.base.color),
         border: Border {
             radius: 2.0.into(),
@@ -1455,21 +1466,21 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
 
     match status {
         Status::Active => active,
-        Status::Hovered => Appearance {
+        Status::Hovered => Style {
             border: Border {
                 color: palette.background.base.text,
                 ..active.border
             },
             ..active
         },
-        Status::Focused => Appearance {
+        Status::Focused => Style {
             border: Border {
                 color: palette.primary.strong.color,
                 ..active.border
             },
             ..active
         },
-        Status::Disabled => Appearance {
+        Status::Disabled => Style {
             background: Background::Color(palette.background.weak.color),
             value: active.placeholder,
             ..active
diff --git a/widget/src/themer.rs b/widget/src/themer.rs
index a7eabd2c..f4597458 100644
--- a/widget/src/themer.rs
+++ b/widget/src/themer.rs
@@ -155,9 +155,9 @@ where
         if let Some(background) = self.background {
             container::draw_background(
                 renderer,
-                &container::Appearance {
+                &container::Style {
                     background: Some(background(&theme)),
-                    ..container::Appearance::default()
+                    ..container::Style::default()
                 },
                 layout.bounds(),
             );
diff --git a/widget/src/toggler.rs b/widget/src/toggler.rs
index fc9e06e1..ca6e37b0 100644
--- a/widget/src/toggler.rs
+++ b/widget/src/toggler.rs
@@ -35,6 +35,7 @@ pub struct Toggler<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     is_toggled: bool,
@@ -48,11 +49,12 @@ pub struct Toggler<
     text_shaping: text::Shaping,
     spacing: f32,
     font: Option<Renderer::Font>,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Toggler<'a, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     /// The default size of a [`Toggler`].
@@ -72,7 +74,6 @@ where
         f: F,
     ) -> Self
     where
-        Theme: 'a + DefaultStyle,
         F: 'a + Fn(bool) -> Message,
     {
         Toggler {
@@ -87,7 +88,7 @@ where
             text_shaping: text::Shaping::Basic,
             spacing: Self::DEFAULT_SIZE / 2.0,
             font: None,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -145,11 +146,20 @@ where
     }
 
     /// Sets the style of the [`Toggler`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Toggler`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -157,6 +167,7 @@ where
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Toggler<'a, Message, Theme, Renderer>
 where
+    Theme: Catalog,
     Renderer: text::Renderer,
 {
     fn tag(&self) -> tree::Tag {
@@ -284,7 +295,7 @@ where
                 style,
                 label_layout,
                 tree.state.downcast_ref(),
-                crate::text::Appearance::default(),
+                crate::text::Style::default(),
                 viewport,
             );
         }
@@ -302,7 +313,7 @@ where
             }
         };
 
-        let appearance = (self.style)(theme, status);
+        let style = theme.style(&self.class, status);
 
         let border_radius = bounds.height / BORDER_RADIUS_RATIO;
         let space = SPACE_RATIO * bounds.height;
@@ -319,12 +330,12 @@ where
                 bounds: toggler_background_bounds,
                 border: Border {
                     radius: border_radius.into(),
-                    width: appearance.background_border_width,
-                    color: appearance.background_border_color,
+                    width: style.background_border_width,
+                    color: style.background_border_color,
                 },
                 ..renderer::Quad::default()
             },
-            appearance.background,
+            style.background,
         );
 
         let toggler_foreground_bounds = Rectangle {
@@ -344,12 +355,12 @@ where
                 bounds: toggler_foreground_bounds,
                 border: Border {
                     radius: border_radius.into(),
-                    width: appearance.foreground_border_width,
-                    color: appearance.foreground_border_color,
+                    width: style.foreground_border_width,
+                    color: style.foreground_border_color,
                 },
                 ..renderer::Quad::default()
             },
-            appearance.foreground,
+            style.foreground,
         );
     }
 }
@@ -358,7 +369,7 @@ impl<'a, Message, Theme, Renderer> From<Toggler<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(
@@ -385,7 +396,7 @@ pub enum Status {
 
 /// The appearance of a toggler.
 #[derive(Debug, Clone, Copy)]
-pub struct Appearance {
+pub struct Style {
     /// The background [`Color`] of the toggler.
     pub background: Color,
     /// The width of the background border of the toggler.
@@ -400,29 +411,37 @@ pub struct Appearance {
     pub foreground_border_color: Color,
 }
 
-/// The style of a [`Toggler`].
-pub type Style<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Appearance + 'a>;
+/// The theme catalog of a [`Toggler`].
+pub trait Catalog: Sized {
+    /// The item class of the [`Catalog`].
+    type Class<'a>;
 
-/// The default style of a [`Toggler`].
-pub trait DefaultStyle {
-    /// Returns the default style of a [`Toggler`].
-    fn default_style(&self, status: Status) -> Appearance;
+    /// The default class produced by the [`Catalog`].
+    fn default<'a>() -> Self::Class<'a>;
+
+    /// The [`Style`] of a class with the given status.
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style;
 }
 
-impl DefaultStyle for Theme {
-    fn default_style(&self, status: Status) -> Appearance {
-        default(self, status)
+/// A styling function for a [`Toggler`].
+///
+/// This is just a boxed closure: `Fn(&Theme, Status) -> Style`.
+pub type StyleFn<'a, Theme> = Box<dyn Fn(&Theme, Status) -> Style + 'a>;
+
+impl Catalog for Theme {
+    type Class<'a> = StyleFn<'a, Self>;
+
+    fn default<'a>() -> Self::Class<'a> {
+        Box::new(default)
     }
-}
 
-impl DefaultStyle for Appearance {
-    fn default_style(&self, _status: Status) -> Appearance {
-        *self
+    fn style(&self, class: &Self::Class<'_>, status: Status) -> Style {
+        class(self, status)
     }
 }
 
 /// The default style of a [`Toggler`].
-pub fn default(theme: &Theme, status: Status) -> Appearance {
+pub fn default(theme: &Theme, status: Status) -> Style {
     let palette = theme.extended_palette();
 
     let background = match status {
@@ -455,7 +474,7 @@ pub fn default(theme: &Theme, status: Status) -> Appearance {
         }
     };
 
-    Appearance {
+    Style {
         background,
         foreground,
         foreground_border_width: 0.0,
diff --git a/widget/src/tooltip.rs b/widget/src/tooltip.rs
index 32c962fc..39f2e07d 100644
--- a/widget/src/tooltip.rs
+++ b/widget/src/tooltip.rs
@@ -20,6 +20,7 @@ pub struct Tooltip<
     Theme = crate::Theme,
     Renderer = crate::Renderer,
 > where
+    Theme: container::Catalog,
     Renderer: text::Renderer,
 {
     content: Element<'a, Message, Theme, Renderer>,
@@ -28,11 +29,12 @@ pub struct Tooltip<
     gap: f32,
     padding: f32,
     snap_within_viewport: bool,
-    style: container::Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, Message, Theme, Renderer> Tooltip<'a, Message, Theme, Renderer>
 where
+    Theme: container::Catalog,
     Renderer: text::Renderer,
 {
     /// The default padding of a [`Tooltip`] drawn by this renderer.
@@ -45,10 +47,7 @@ where
         content: impl Into<Element<'a, Message, Theme, Renderer>>,
         tooltip: impl Into<Element<'a, Message, Theme, Renderer>>,
         position: Position,
-    ) -> Self
-    where
-        Theme: container::DefaultStyle + 'a,
-    {
+    ) -> Self {
         Tooltip {
             content: content.into(),
             tooltip: tooltip.into(),
@@ -56,7 +55,7 @@ where
             gap: 0.0,
             padding: Self::DEFAULT_PADDING,
             snap_within_viewport: true,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -79,11 +78,23 @@ where
     }
 
     /// Sets the style of the [`Tooltip`].
+    #[must_use]
     pub fn style(
         mut self,
-        style: impl Fn(&Theme, container::Status) -> container::Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
+        style: impl Fn(&Theme) -> container::Style + 'a,
+    ) -> Self
+    where
+        Theme::Class<'a>: From<container::StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as container::StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`Tooltip`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
         self
     }
 }
@@ -91,6 +102,7 @@ where
 impl<'a, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
     for Tooltip<'a, Message, Theme, Renderer>
 where
+    Theme: container::Catalog,
     Renderer: text::Renderer,
 {
     fn children(&self) -> Vec<widget::Tree> {
@@ -239,7 +251,7 @@ where
                 positioning: self.position,
                 gap: self.gap,
                 padding: self.padding,
-                style: &self.style,
+                class: &self.class,
             })))
         } else {
             None
@@ -262,7 +274,7 @@ impl<'a, Message, Theme, Renderer> From<Tooltip<'a, Message, Theme, Renderer>>
     for Element<'a, Message, Theme, Renderer>
 where
     Message: 'a,
-    Theme: 'a,
+    Theme: container::Catalog + 'a,
     Renderer: text::Renderer + 'a,
 {
     fn from(
@@ -299,6 +311,7 @@ enum State {
 
 struct Overlay<'a, 'b, Message, Theme, Renderer>
 where
+    Theme: container::Catalog,
     Renderer: text::Renderer,
 {
     position: Point,
@@ -310,14 +323,14 @@ where
     positioning: Position,
     gap: f32,
     padding: f32,
-    style:
-        &'b (dyn Fn(&Theme, container::Status) -> container::Appearance + 'a),
+    class: &'b Theme::Class<'a>,
 }
 
 impl<'a, 'b, Message, Theme, Renderer>
     overlay::Overlay<Message, Theme, Renderer>
     for Overlay<'a, 'b, Message, Theme, Renderer>
 where
+    Theme: container::Catalog,
     Renderer: text::Renderer,
 {
     fn layout(&mut self, renderer: &Renderer, bounds: Size) -> layout::Node {
@@ -426,7 +439,7 @@ where
         layout: Layout<'_>,
         cursor_position: mouse::Cursor,
     ) {
-        let style = (self.style)(theme, container::Status::Idle);
+        let style = theme.style(self.class);
 
         container::draw_background(renderer, &style, layout.bounds());
 
diff --git a/widget/src/vertical_slider.rs b/widget/src/vertical_slider.rs
index 2aa8f4d1..defb442f 100644
--- a/widget/src/vertical_slider.rs
+++ b/widget/src/vertical_slider.rs
@@ -2,10 +2,9 @@
 use std::ops::RangeInclusive;
 
 pub use crate::slider::{
-    default, Appearance, DefaultStyle, Handle, HandleShape, Status, Style,
+    default, Catalog, Handle, HandleShape, Status, Style, StyleFn,
 };
 
-use crate::core;
 use crate::core::event::{self, Event};
 use crate::core::keyboard;
 use crate::core::keyboard::key::{self, Key};
@@ -15,8 +14,8 @@ use crate::core::renderer;
 use crate::core::touch;
 use crate::core::widget::tree::{self, Tree};
 use crate::core::{
-    Border, Clipboard, Element, Length, Pixels, Point, Rectangle, Shell, Size,
-    Widget,
+    self, Border, Clipboard, Element, Length, Pixels, Point, Rectangle, Shell,
+    Size, Widget,
 };
 
 /// An vertical bar and a handle that selects a single value from a range of
@@ -41,7 +40,10 @@ use crate::core::{
 /// VerticalSlider::new(0.0..=100.0, value, Message::SliderChanged);
 /// ```
 #[allow(missing_debug_implementations)]
-pub struct VerticalSlider<'a, T, Message, Theme = crate::Theme> {
+pub struct VerticalSlider<'a, T, Message, Theme = crate::Theme>
+where
+    Theme: Catalog,
+{
     range: RangeInclusive<T>,
     step: T,
     shift_step: Option<T>,
@@ -51,13 +53,14 @@ pub struct VerticalSlider<'a, T, Message, Theme = crate::Theme> {
     on_release: Option<Message>,
     width: f32,
     height: Length,
-    style: Style<'a, Theme>,
+    class: Theme::Class<'a>,
 }
 
 impl<'a, T, Message, Theme> VerticalSlider<'a, T, Message, Theme>
 where
     T: Copy + From<u8> + std::cmp::PartialOrd,
     Message: Clone,
+    Theme: Catalog,
 {
     /// The default width of a [`VerticalSlider`].
     pub const DEFAULT_WIDTH: f32 = 16.0;
@@ -72,7 +75,6 @@ where
     ///   `Message`.
     pub fn new<F>(range: RangeInclusive<T>, value: T, on_change: F) -> Self
     where
-        Theme: DefaultStyle + 'a,
         F: 'a + Fn(T) -> Message,
     {
         let value = if value >= *range.start() {
@@ -97,7 +99,7 @@ where
             on_release: None,
             width: Self::DEFAULT_WIDTH,
             height: Length::Fill,
-            style: Box::new(Theme::default_style),
+            class: Theme::default(),
         }
     }
 
@@ -132,15 +134,6 @@ where
         self
     }
 
-    /// Sets the style of the [`VerticalSlider`].
-    pub fn style(
-        mut self,
-        style: impl Fn(&Theme, Status) -> Appearance + 'a,
-    ) -> Self {
-        self.style = Box::new(style);
-        self
-    }
-
     /// Sets the step size of the [`VerticalSlider`].
     pub fn step(mut self, step: T) -> Self {
         self.step = step;
@@ -154,6 +147,24 @@ where
         self.shift_step = Some(shift_step.into());
         self
     }
+
+    /// Sets the style of the [`VerticalSlider`].
+    #[must_use]
+    pub fn style(mut self, style: impl Fn(&Theme, Status) -> Style + 'a) -> Self
+    where
+        Theme::Class<'a>: From<StyleFn<'a, Theme>>,
+    {
+        self.class = (Box::new(style) as StyleFn<'a, Theme>).into();
+        self
+    }
+
+    /// Sets the style class of the [`VerticalSlider`].
+    #[cfg(feature = "advanced")]
+    #[must_use]
+    pub fn class(mut self, class: impl Into<Theme::Class<'a>>) -> Self {
+        self.class = class.into();
+        self
+    }
 }
 
 impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
@@ -161,6 +172,7 @@ impl<'a, T, Message, Theme, Renderer> Widget<Message, Theme, Renderer>
 where
     T: Copy + Into<f64> + num_traits::FromPrimitive,
     Message: Clone,
+    Theme: Catalog,
     Renderer: core::Renderer,
 {
     fn tag(&self) -> tree::Tag {
@@ -354,8 +366,8 @@ where
         let bounds = layout.bounds();
         let is_mouse_over = cursor.is_over(bounds);
 
-        let style = (self.style)(
-            theme,
+        let style = theme.style(
+            &self.class,
             if state.is_dragging {
                 Status::Dragged
             } else if is_mouse_over {
@@ -467,7 +479,7 @@ impl<'a, T, Message, Theme, Renderer>
 where
     T: Copy + Into<f64> + num_traits::FromPrimitive + 'a,
     Message: Clone + 'a,
-    Theme: 'a,
+    Theme: Catalog + 'a,
     Renderer: core::Renderer + 'a,
 {
     fn from(