diff --git a/crates/bevy_ui/src/flex/convert.rs b/crates/bevy_ui/src/flex/convert.rs
index 7ebc0fd0cd30e9..60e22f0e0b9ba6 100644
--- a/crates/bevy_ui/src/flex/convert.rs
+++ b/crates/bevy_ui/src/flex/convert.rs
@@ -11,13 +11,12 @@ impl Val {
             Val::Auto => Val::Auto,
             Val::Percent(value) => Val::Percent(value),
             Val::Px(value) => Val::Px((scale_factor * value as f64) as f32),
-            Val::Undefined => Val::Undefined,
         }
     }
 
     fn to_inset(self) -> LengthPercentageAuto {
         match self {
-            Val::Auto | Val::Undefined => taffy::style::LengthPercentageAuto::Auto,
+            Val::Auto => taffy::style::LengthPercentageAuto::Auto,
             Val::Percent(value) => taffy::style::LengthPercentageAuto::Percent(value / 100.0),
             Val::Px(value) => taffy::style::LengthPercentageAuto::Points(value),
         }
@@ -67,7 +66,7 @@ impl<T: From<Val>> From<Size> for taffy::prelude::Size<T> {
 impl From<Val> for taffy::style::Dimension {
     fn from(value: Val) -> Self {
         match value {
-            Val::Auto | Val::Undefined => taffy::style::Dimension::Auto,
+            Val::Auto => taffy::style::Dimension::Auto,
             Val::Percent(value) => taffy::style::Dimension::Percent(value / 100.0),
             Val::Px(value) => taffy::style::Dimension::Points(value),
         }
@@ -77,7 +76,7 @@ impl From<Val> for taffy::style::Dimension {
 impl From<Val> for taffy::style::LengthPercentage {
     fn from(value: Val) -> Self {
         match value {
-            Val::Auto | Val::Undefined => taffy::style::LengthPercentage::Points(0.0),
+            Val::Auto => taffy::style::LengthPercentage::Points(0.0),
             Val::Percent(value) => taffy::style::LengthPercentage::Percent(value / 100.0),
             Val::Px(value) => taffy::style::LengthPercentage::Points(value),
         }
@@ -90,7 +89,6 @@ impl From<Val> for taffy::style::LengthPercentageAuto {
             Val::Auto => taffy::style::LengthPercentageAuto::Auto,
             Val::Percent(value) => taffy::style::LengthPercentageAuto::Percent(value / 100.0),
             Val::Px(value) => taffy::style::LengthPercentageAuto::Points(value),
-            Val::Undefined => taffy::style::LengthPercentageAuto::Points(0.),
         }
     }
 }
@@ -106,10 +104,10 @@ pub fn from_style(scale_factor: f64, style: &Style) -> taffy::style::Style {
         align_content: Some(style.align_content.into()),
         justify_content: Some(style.justify_content.into()),
         inset: taffy::prelude::Rect {
-            left: style.position.left.scaled(scale_factor).to_inset(),
-            right: style.position.right.scaled(scale_factor).to_inset(),
-            top: style.position.top.scaled(scale_factor).to_inset(),
-            bottom: style.position.bottom.scaled(scale_factor).to_inset(),
+            left: style.left.scaled(scale_factor).to_inset(),
+            right: style.right.scaled(scale_factor).to_inset(),
+            top: style.top.scaled(scale_factor).to_inset(),
+            bottom: style.bottom.scaled(scale_factor).to_inset(),
         },
         margin: style.margin.scaled(scale_factor).into(),
         padding: style.padding.scaled(scale_factor).into(),
@@ -224,3 +222,190 @@ impl From<FlexWrap> for taffy::style::FlexWrap {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_convert_from() {
+        let bevy_style = crate::Style {
+            display: Display::Flex,
+            position_type: PositionType::Absolute,
+            left: Val::Px(0.),
+            right: Val::Percent(0.),
+            top: Val::Auto,
+            bottom: Val::Auto,
+            direction: crate::Direction::Inherit,
+            flex_direction: FlexDirection::ColumnReverse,
+            flex_wrap: FlexWrap::WrapReverse,
+            align_items: AlignItems::Baseline,
+            align_self: AlignSelf::Start,
+            align_content: AlignContent::SpaceAround,
+            justify_content: JustifyContent::SpaceEvenly,
+            margin: UiRect {
+                left: Val::Percent(0.),
+                right: Val::Px(0.),
+                top: Val::Auto,
+                bottom: Val::Auto,
+            },
+            padding: UiRect {
+                left: Val::Percent(0.),
+                right: Val::Px(0.),
+                top: Val::Percent(0.),
+                bottom: Val::Percent(0.),
+            },
+            border: UiRect {
+                left: Val::Px(0.),
+                right: Val::Px(0.),
+                top: Val::Auto,
+                bottom: Val::Px(0.),
+            },
+            flex_grow: 1.,
+            flex_shrink: 0.,
+            flex_basis: Val::Px(0.),
+            size: Size {
+                width: Val::Px(0.),
+                height: Val::Auto,
+            },
+            min_size: Size {
+                width: Val::Px(0.),
+                height: Val::Percent(0.),
+            },
+            max_size: Size {
+                width: Val::Auto,
+                height: Val::Px(0.),
+            },
+            aspect_ratio: None,
+            overflow: crate::Overflow::Hidden,
+            gap: Size {
+                width: Val::Px(0.),
+                height: Val::Percent(0.),
+            },
+        };
+        let taffy_style = from_style(1.0, &bevy_style);
+        assert_eq!(taffy_style.display, taffy::style::Display::Flex);
+        assert_eq!(taffy_style.position, taffy::style::Position::Absolute);
+        assert!(matches!(
+            taffy_style.inset.left,
+            taffy::style::LengthPercentageAuto::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.inset.right,
+            taffy::style::LengthPercentageAuto::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.inset.top,
+            taffy::style::LengthPercentageAuto::Auto
+        ));
+        assert!(matches!(
+            taffy_style.inset.bottom,
+            taffy::style::LengthPercentageAuto::Auto
+        ));
+        assert_eq!(
+            taffy_style.flex_direction,
+            taffy::style::FlexDirection::ColumnReverse
+        );
+        assert_eq!(taffy_style.flex_wrap, taffy::style::FlexWrap::WrapReverse);
+        assert_eq!(
+            taffy_style.align_items,
+            Some(taffy::style::AlignItems::Baseline)
+        );
+        assert_eq!(taffy_style.align_self, Some(taffy::style::AlignSelf::Start));
+        assert_eq!(
+            taffy_style.align_content,
+            Some(taffy::style::AlignContent::SpaceAround)
+        );
+        assert_eq!(
+            taffy_style.justify_content,
+            Some(taffy::style::JustifyContent::SpaceEvenly)
+        );
+        assert!(matches!(
+            taffy_style.margin.left,
+            taffy::style::LengthPercentageAuto::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.margin.right,
+            taffy::style::LengthPercentageAuto::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.margin.top,
+            taffy::style::LengthPercentageAuto::Auto
+        ));
+        assert!(matches!(
+            taffy_style.margin.bottom,
+            taffy::style::LengthPercentageAuto::Auto
+        ));
+        assert!(matches!(
+            taffy_style.padding.left,
+            taffy::style::LengthPercentage::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.padding.right,
+            taffy::style::LengthPercentage::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.padding.top,
+            taffy::style::LengthPercentage::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.padding.bottom,
+            taffy::style::LengthPercentage::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.border.left,
+            taffy::style::LengthPercentage::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.border.right,
+            taffy::style::LengthPercentage::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.border.top,
+            taffy::style::LengthPercentage::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.border.bottom,
+            taffy::style::LengthPercentage::Points(_)
+        ));
+        assert_eq!(taffy_style.flex_grow, 1.);
+        assert_eq!(taffy_style.flex_shrink, 0.);
+        assert!(matches!(
+            taffy_style.flex_basis,
+            taffy::style::Dimension::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.size.width,
+            taffy::style::Dimension::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.size.height,
+            taffy::style::Dimension::Auto
+        ));
+        assert!(matches!(
+            taffy_style.min_size.width,
+            taffy::style::Dimension::Points(_)
+        ));
+        assert!(matches!(
+            taffy_style.min_size.height,
+            taffy::style::Dimension::Percent(_)
+        ));
+        assert!(matches!(
+            taffy_style.max_size.width,
+            taffy::style::Dimension::Auto
+        ));
+        assert!(matches!(
+            taffy_style.max_size.height,
+            taffy::style::Dimension::Points(_)
+        ));
+        assert_eq!(taffy_style.aspect_ratio, None);
+        assert_eq!(
+            taffy_style.gap.width,
+            taffy::style::LengthPercentage::Points(0.)
+        );
+        assert_eq!(
+            taffy_style.gap.height,
+            taffy::style::LengthPercentage::Percent(0.)
+        );
+    }
+}
diff --git a/crates/bevy_ui/src/geometry.rs b/crates/bevy_ui/src/geometry.rs
index fd90c711c993a3..ac70c93834d326 100644
--- a/crates/bevy_ui/src/geometry.rs
+++ b/crates/bevy_ui/src/geometry.rs
@@ -2,83 +2,10 @@ use crate::Val;
 use bevy_reflect::Reflect;
 use std::ops::{Div, DivAssign, Mul, MulAssign};
 
-/// A type which is commonly used to define positions, margins, paddings and borders.
+/// A type which is commonly used to define margins, paddings and borders.
 ///
 /// # Examples
-///
-/// ## Position
-///
-/// A position is used to determine where to place a UI element.
-///
-/// ```
-/// # use bevy_ui::{UiRect, Val};
-/// # use bevy_utils::default;
-/// #
-/// let position = UiRect {
-///     left: Val::Px(100.0),
-///     top: Val::Px(50.0),
-///     ..default()
-/// };
-/// ```
-///
-/// If you define opposite sides of the position, the size of the UI element will automatically be calculated
-/// if not explicitly specified. This means that if you have a [`Size`] that uses [`Val::Undefined`](crate::Val::Undefined)
-/// as a width and height, the size would be determined by the window size and the values specified in the position.
-///
-/// ```
-/// # use bevy_ui::{UiRect, Val};
-/// #
-/// let position = UiRect {
-///     left: Val::Px(100.0),
-///     right: Val::Px(200.0),
-///     top: Val::Px(300.0),
-///     bottom: Val::Px(400.0),
-/// };
-/// ```
-///
-/// To determine the width of the UI element you have to take the width of the window and subtract it by the
-/// left and right values of the position. To determine the height of the UI element you have to take the height
-/// of the window and subtract it by the top and bottom values of the position. If we had a window with a width
-/// and height of 1000px, the UI element declared above would have a width of 700px and a height of 300px.
-///
-/// ```
-/// // Size of the window
-/// let window_width = 1000.0;
-/// let window_height = 1000.0;
-///
-/// // Values of the position
-/// let left = 100.0;
-/// let right = 200.0;
-/// let top = 300.0;
-/// let bottom = 400.0;
-///
-/// // Calculation to get the size of the UI element
-/// let ui_element_width = window_width - left - right;
-/// let ui_element_height = window_height - top - bottom;
-///
-/// assert_eq!(ui_element_width, 700.0);
-/// assert_eq!(ui_element_height, 300.0);
-/// ```
-///
-/// If you define a [`Size`] and also all four sides of the position, the top and left values of the position
-/// are used to determine where to place the UI element. The size will not be calculated using the bottom and
-/// right values of the position because the size of the UI element is already explicitly specified.
-///
-/// ```
-/// # use bevy_ui::{UiRect, Size, Val, Style};
-/// # use bevy_utils::default;
-/// #
-/// let style = Style {
-///     position: UiRect { // Defining all four sides
-///         left: Val::Px(100.0),
-///         right: Val::Px(200.0),
-///         top: Val::Px(300.0),
-///         bottom: Val::Px(400.0),
-///     },
-///     size: Size::new(Val::Percent(100.0), Val::Percent(50.0)), // but also explicitly specifying a size
-///     ..default()
-/// };
-/// ```
+
 ///
 /// ## Margin
 ///
@@ -134,10 +61,10 @@ pub struct UiRect {
 
 impl UiRect {
     pub const DEFAULT: Self = Self {
-        left: Val::DEFAULT,
-        right: Val::DEFAULT,
-        top: Val::DEFAULT,
-        bottom: Val::DEFAULT,
+        left: Val::Px(0.),
+        right: Val::Px(0.),
+        top: Val::Px(0.),
+        bottom: Val::Px(0.),
     };
 
     /// Creates a new [`UiRect`] from the values specified.
@@ -191,7 +118,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `left` and `right` take the given value.
+    /// Creates a new [`UiRect`] where `left` and `right` take the given value,
+    /// and `top` and `bottom` set to zero `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -202,8 +130,8 @@ impl UiRect {
     ///
     /// assert_eq!(ui_rect.left, Val::Px(10.0));
     /// assert_eq!(ui_rect.right, Val::Px(10.0));
-    /// assert_eq!(ui_rect.top, Val::Undefined);
-    /// assert_eq!(ui_rect.bottom, Val::Undefined);
+    /// assert_eq!(ui_rect.top, Val::Px(0.));
+    /// assert_eq!(ui_rect.bottom, Val::Px(0.));
     /// ```
     pub fn horizontal(value: Val) -> Self {
         UiRect {
@@ -213,7 +141,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `top` and `bottom` take the given value.
+    /// Creates a new [`UiRect`] where `top` and `bottom` take the given value,
+    /// and `left` and `right` are set to `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -222,8 +151,8 @@ impl UiRect {
     /// #
     /// let ui_rect = UiRect::vertical(Val::Px(10.0));
     ///
-    /// assert_eq!(ui_rect.left, Val::Undefined);
-    /// assert_eq!(ui_rect.right, Val::Undefined);
+    /// assert_eq!(ui_rect.left, Val::Px(0.));
+    /// assert_eq!(ui_rect.right, Val::Px(0.));
     /// assert_eq!(ui_rect.top, Val::Px(10.0));
     /// assert_eq!(ui_rect.bottom, Val::Px(10.0));
     /// ```
@@ -235,7 +164,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `left` takes the given value.
+    /// Creates a new [`UiRect`] where `left` takes the given value, and
+    /// the other fields are set to `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -245,9 +175,9 @@ impl UiRect {
     /// let ui_rect = UiRect::left(Val::Px(10.0));
     ///
     /// assert_eq!(ui_rect.left, Val::Px(10.0));
-    /// assert_eq!(ui_rect.right, Val::Undefined);
-    /// assert_eq!(ui_rect.top, Val::Undefined);
-    /// assert_eq!(ui_rect.bottom, Val::Undefined);
+    /// assert_eq!(ui_rect.right, Val::Px(0.));
+    /// assert_eq!(ui_rect.top, Val::Px(0.));
+    /// assert_eq!(ui_rect.bottom, Val::Px(0.));
     /// ```
     pub fn left(value: Val) -> Self {
         UiRect {
@@ -256,7 +186,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `right` takes the given value.
+    /// Creates a new [`UiRect`] where `right` takes the given value,
+    /// and the other fields are set to `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -265,10 +196,10 @@ impl UiRect {
     /// #
     /// let ui_rect = UiRect::right(Val::Px(10.0));
     ///
-    /// assert_eq!(ui_rect.left, Val::Undefined);
+    /// assert_eq!(ui_rect.left, Val::Px(0.));
     /// assert_eq!(ui_rect.right, Val::Px(10.0));
-    /// assert_eq!(ui_rect.top, Val::Undefined);
-    /// assert_eq!(ui_rect.bottom, Val::Undefined);
+    /// assert_eq!(ui_rect.top, Val::Px(0.));
+    /// assert_eq!(ui_rect.bottom, Val::Px(0.));
     /// ```
     pub fn right(value: Val) -> Self {
         UiRect {
@@ -277,7 +208,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `top` takes the given value.
+    /// Creates a new [`UiRect`] where `top` takes the given value,
+    /// and the other fields are set to `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -286,10 +218,10 @@ impl UiRect {
     /// #
     /// let ui_rect = UiRect::top(Val::Px(10.0));
     ///
-    /// assert_eq!(ui_rect.left, Val::Undefined);
-    /// assert_eq!(ui_rect.right, Val::Undefined);
+    /// assert_eq!(ui_rect.left, Val::Px(0.));
+    /// assert_eq!(ui_rect.right, Val::Px(0.));
     /// assert_eq!(ui_rect.top, Val::Px(10.0));
-    /// assert_eq!(ui_rect.bottom, Val::Undefined);
+    /// assert_eq!(ui_rect.bottom, Val::Px(0.));
     /// ```
     pub fn top(value: Val) -> Self {
         UiRect {
@@ -298,7 +230,8 @@ impl UiRect {
         }
     }
 
-    /// Creates a new [`UiRect`] where `bottom` takes the given value.
+    /// Creates a new [`UiRect`] where `bottom` takes the given value,
+    /// and the other fields are set to `Val::Px(0.)`.
     ///
     /// # Example
     ///
@@ -307,9 +240,9 @@ impl UiRect {
     /// #
     /// let ui_rect = UiRect::bottom(Val::Px(10.0));
     ///
-    /// assert_eq!(ui_rect.left, Val::Undefined);
-    /// assert_eq!(ui_rect.right, Val::Undefined);
-    /// assert_eq!(ui_rect.top, Val::Undefined);
+    /// assert_eq!(ui_rect.left, Val::Px(0.));
+    /// assert_eq!(ui_rect.right, Val::Px(0.));
+    /// assert_eq!(ui_rect.top, Val::Px(0.));
     /// assert_eq!(ui_rect.bottom, Val::Px(10.0));
     /// ```
     pub fn bottom(value: Val) -> Self {
@@ -376,7 +309,9 @@ impl Size {
         }
     }
 
-    /// Creates a new [`Size`] where `width` takes the given value and its `height` is `Val::Auto`.
+    /// Creates a new [`Size`] where `width` takes the given value,
+    /// and `height` is set to [`Val::Auto`].
+
     ///
     /// # Example
     ///
@@ -395,7 +330,8 @@ impl Size {
         }
     }
 
-    /// Creates a new [`Size`] where `height` takes the given value and its `width` is `Val::Auto`.
+    /// Creates a new [`Size`] where `height` takes the given value,
+    /// and `width` is set to [`Val::Auto`].
     ///
     /// # Example
     ///
@@ -416,9 +352,6 @@ impl Size {
 
     /// Creates a Size where both values are [`Val::Auto`].
     pub const AUTO: Self = Self::all(Val::Auto);
-
-    /// Creates a Size where both values are [`Val::Undefined`].
-    pub const UNDEFINED: Self = Self::all(Val::Undefined);
 }
 
 impl Default for Size {
@@ -481,10 +414,10 @@ mod tests {
         assert_eq!(
             UiRect::default(),
             UiRect {
-                left: Val::Undefined,
-                right: Val::Undefined,
-                top: Val::Undefined,
-                bottom: Val::Undefined
+                left: Val::Px(0.),
+                right: Val::Px(0.),
+                top: Val::Px(0.),
+                bottom: Val::Px(0.)
             }
         );
         assert_eq!(UiRect::default(), UiRect::DEFAULT);
diff --git a/crates/bevy_ui/src/ui_node.rs b/crates/bevy_ui/src/ui_node.rs
index 52290aa3a5f565..2a28c5a1e508c7 100644
--- a/crates/bevy_ui/src/ui_node.rs
+++ b/crates/bevy_ui/src/ui_node.rs
@@ -61,8 +61,6 @@ impl Default for Node {
 #[derive(Copy, Clone, PartialEq, Debug, Serialize, Deserialize, Reflect)]
 #[reflect(PartialEq, Serialize, Deserialize)]
 pub enum Val {
-    /// No value defined
-    Undefined,
     /// Automatically determine this value
     Auto,
     /// Set this value in pixels
@@ -72,7 +70,7 @@ pub enum Val {
 }
 
 impl Val {
-    pub const DEFAULT: Self = Self::Undefined;
+    pub const DEFAULT: Self = Self::Auto;
 }
 
 impl Default for Val {
@@ -86,7 +84,6 @@ impl Mul<f32> for Val {
 
     fn mul(self, rhs: f32) -> Self::Output {
         match self {
-            Val::Undefined => Val::Undefined,
             Val::Auto => Val::Auto,
             Val::Px(value) => Val::Px(value * rhs),
             Val::Percent(value) => Val::Percent(value * rhs),
@@ -97,7 +94,7 @@ impl Mul<f32> for Val {
 impl MulAssign<f32> for Val {
     fn mul_assign(&mut self, rhs: f32) {
         match self {
-            Val::Undefined | Val::Auto => {}
+            Val::Auto => {}
             Val::Px(value) | Val::Percent(value) => *value *= rhs,
         }
     }
@@ -108,7 +105,6 @@ impl Div<f32> for Val {
 
     fn div(self, rhs: f32) -> Self::Output {
         match self {
-            Val::Undefined => Val::Undefined,
             Val::Auto => Val::Auto,
             Val::Px(value) => Val::Px(value / rhs),
             Val::Percent(value) => Val::Percent(value / rhs),
@@ -119,7 +115,7 @@ impl Div<f32> for Val {
 impl DivAssign<f32> for Val {
     fn div_assign(&mut self, rhs: f32) {
         match self {
-            Val::Undefined | Val::Auto => {}
+            Val::Auto => {}
             Val::Px(value) | Val::Percent(value) => *value /= rhs,
         }
     }
@@ -139,7 +135,7 @@ impl Val {
     /// When adding non-numeric [`Val`]s, it returns the value unchanged.
     pub fn try_add(&self, rhs: Val) -> Result<Val, ValArithmeticError> {
         match (self, rhs) {
-            (Val::Undefined, Val::Undefined) | (Val::Auto, Val::Auto) => Ok(*self),
+            (Val::Auto, Val::Auto) => Ok(*self),
             (Val::Px(value), Val::Px(rhs_value)) => Ok(Val::Px(value + rhs_value)),
             (Val::Percent(value), Val::Percent(rhs_value)) => Ok(Val::Percent(value + rhs_value)),
             _ => Err(ValArithmeticError::NonIdenticalVariants),
@@ -157,7 +153,7 @@ impl Val {
     /// When adding non-numeric [`Val`]s, it returns the value unchanged.
     pub fn try_sub(&self, rhs: Val) -> Result<Val, ValArithmeticError> {
         match (self, rhs) {
-            (Val::Undefined, Val::Undefined) | (Val::Auto, Val::Auto) => Ok(*self),
+            (Val::Auto, Val::Auto) => Ok(*self),
             (Val::Px(value), Val::Px(rhs_value)) => Ok(Val::Px(value - rhs_value)),
             (Val::Percent(value), Val::Percent(rhs_value)) => Ok(Val::Percent(value - rhs_value)),
             _ => Err(ValArithmeticError::NonIdenticalVariants),
@@ -236,6 +232,10 @@ pub struct Style {
     pub display: Display,
     /// Whether to arrange this node relative to other nodes, or positioned absolutely
     pub position_type: PositionType,
+    pub left: Val,
+    pub right: Val,
+    pub top: Val,
+    pub bottom: Val,
     /// Which direction the content of this node should go
     pub direction: Direction,
     /// Whether to use column or row layout
@@ -252,8 +252,6 @@ pub struct Style {
     pub align_content: AlignContent,
     /// How items align according to the main axis
     pub justify_content: JustifyContent,
-    /// The position of the node as described by its Rect
-    pub position: UiRect,
     /// The amount of space around a node outside its border.
     ///
     /// If a percentage value is used, the percentage is calculated based on the width of the parent node.
@@ -329,7 +327,7 @@ pub struct Style {
     pub overflow: Overflow,
     /// The size of the gutters between the rows and columns of the flexbox layout
     ///
-    /// Values of `Size::UNDEFINED` and `Size::AUTO` are treated as zero.
+    /// A value of `Size::AUTO` is treated as zero.
     pub gap: Size,
 }
 
@@ -337,6 +335,10 @@ impl Style {
     pub const DEFAULT: Self = Self {
         display: Display::DEFAULT,
         position_type: PositionType::DEFAULT,
+        left: Val::Auto,
+        right: Val::Auto,
+        top: Val::Auto,
+        bottom: Val::Auto,
         direction: Direction::DEFAULT,
         flex_direction: FlexDirection::DEFAULT,
         flex_wrap: FlexWrap::DEFAULT,
@@ -344,7 +346,6 @@ impl Style {
         align_self: AlignSelf::DEFAULT,
         align_content: AlignContent::DEFAULT,
         justify_content: JustifyContent::DEFAULT,
-        position: UiRect::DEFAULT,
         margin: UiRect::DEFAULT,
         padding: UiRect::DEFAULT,
         border: UiRect::DEFAULT,
@@ -356,7 +357,7 @@ impl Style {
         max_size: Size::AUTO,
         aspect_ratio: None,
         overflow: Overflow::DEFAULT,
-        gap: Size::UNDEFINED,
+        gap: Size::AUTO,
     };
 }
 
@@ -769,12 +770,10 @@ mod tests {
 
     #[test]
     fn val_try_add() {
-        let undefined_sum = Val::Undefined.try_add(Val::Undefined).unwrap();
         let auto_sum = Val::Auto.try_add(Val::Auto).unwrap();
         let px_sum = Val::Px(20.).try_add(Val::Px(22.)).unwrap();
         let percent_sum = Val::Percent(50.).try_add(Val::Percent(50.)).unwrap();
 
-        assert_eq!(undefined_sum, Val::Undefined);
         assert_eq!(auto_sum, Val::Auto);
         assert_eq!(px_sum, Val::Px(42.));
         assert_eq!(percent_sum, Val::Percent(100.));
@@ -791,12 +790,10 @@ mod tests {
 
     #[test]
     fn val_try_sub() {
-        let undefined_sum = Val::Undefined.try_sub(Val::Undefined).unwrap();
         let auto_sum = Val::Auto.try_sub(Val::Auto).unwrap();
         let px_sum = Val::Px(72.).try_sub(Val::Px(30.)).unwrap();
         let percent_sum = Val::Percent(100.).try_sub(Val::Percent(50.)).unwrap();
 
-        assert_eq!(undefined_sum, Val::Undefined);
         assert_eq!(auto_sum, Val::Auto);
         assert_eq!(px_sum, Val::Px(42.));
         assert_eq!(percent_sum, Val::Percent(50.));
@@ -804,9 +801,8 @@ mod tests {
 
     #[test]
     fn different_variant_val_try_add() {
-        let different_variant_sum_1 = Val::Undefined.try_add(Val::Auto);
-        let different_variant_sum_2 = Val::Px(50.).try_add(Val::Percent(50.));
-        let different_variant_sum_3 = Val::Percent(50.).try_add(Val::Undefined);
+        let different_variant_sum_1 = Val::Px(50.).try_add(Val::Percent(50.));
+        let different_variant_sum_2 = Val::Percent(50.).try_add(Val::Auto);
 
         assert_eq!(
             different_variant_sum_1,
@@ -816,17 +812,12 @@ mod tests {
             different_variant_sum_2,
             Err(ValArithmeticError::NonIdenticalVariants)
         );
-        assert_eq!(
-            different_variant_sum_3,
-            Err(ValArithmeticError::NonIdenticalVariants)
-        );
     }
 
     #[test]
     fn different_variant_val_try_sub() {
-        let different_variant_diff_1 = Val::Undefined.try_sub(Val::Auto);
-        let different_variant_diff_2 = Val::Px(50.).try_sub(Val::Percent(50.));
-        let different_variant_diff_3 = Val::Percent(50.).try_sub(Val::Undefined);
+        let different_variant_diff_1 = Val::Px(50.).try_sub(Val::Percent(50.));
+        let different_variant_diff_2 = Val::Percent(50.).try_sub(Val::Auto);
 
         assert_eq!(
             different_variant_diff_1,
@@ -836,10 +827,6 @@ mod tests {
             different_variant_diff_2,
             Err(ValArithmeticError::NonIdenticalVariants)
         );
-        assert_eq!(
-            different_variant_diff_3,
-            Err(ValArithmeticError::NonIdenticalVariants)
-        );
     }
 
     #[test]
@@ -861,10 +848,8 @@ mod tests {
     #[test]
     fn val_invalid_evaluation() {
         let size = 250.;
-        let evaluate_undefined = Val::Undefined.evaluate(size);
         let evaluate_auto = Val::Auto.evaluate(size);
 
-        assert_eq!(evaluate_undefined, Err(ValArithmeticError::NonEvaluateable));
         assert_eq!(evaluate_auto, Err(ValArithmeticError::NonEvaluateable));
     }
 
@@ -906,10 +891,8 @@ mod tests {
     fn val_try_add_non_numeric_with_size() {
         let size = 250.;
 
-        let undefined_sum = Val::Undefined.try_add_with_size(Val::Undefined, size);
         let percent_sum = Val::Auto.try_add_with_size(Val::Auto, size);
 
-        assert_eq!(undefined_sum, Err(ValArithmeticError::NonEvaluateable));
         assert_eq!(percent_sum, Err(ValArithmeticError::NonEvaluateable));
     }
 
@@ -924,4 +907,9 @@ mod tests {
             "the given variant of Val is not evaluateable (non-numeric)"
         );
     }
+
+    #[test]
+    fn default_val_equals_const_default_val() {
+        assert_eq!(Val::default(), Val::DEFAULT);
+    }
 }
diff --git a/crates/bevy_ui/src/widget/text.rs b/crates/bevy_ui/src/widget/text.rs
index a4464701fdcee4..e3404575e8ee3c 100644
--- a/crates/bevy_ui/src/widget/text.rs
+++ b/crates/bevy_ui/src/widget/text.rs
@@ -25,9 +25,7 @@ pub fn text_constraint(min_size: Val, size: Val, max_size: Val, scale_factor: f6
     match (min_size, size, max_size) {
         (_, _, Val::Px(max)) => scale_value(max, scale_factor),
         (Val::Px(min), _, _) => scale_value(min, scale_factor),
-        (Val::Undefined, Val::Px(size), Val::Undefined) | (Val::Auto, Val::Px(size), Val::Auto) => {
-            scale_value(size, scale_factor)
-        }
+        (Val::Auto, Val::Px(size), Val::Auto) => scale_value(size, scale_factor),
         _ => f32::MAX,
     }
 }
diff --git a/examples/2d/bloom_2d.rs b/examples/2d/bloom_2d.rs
index 825f4803bf4393..3a7ae32a4d503a 100644
--- a/examples/2d/bloom_2d.rs
+++ b/examples/2d/bloom_2d.rs
@@ -78,11 +78,8 @@ fn setup(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            bottom: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
diff --git a/examples/3d/atmospheric_fog.rs b/examples/3d/atmospheric_fog.rs
index 1969303ff75bdd..0bf6d52aba48d2 100644
--- a/examples/3d/atmospheric_fog.rs
+++ b/examples/3d/atmospheric_fog.rs
@@ -101,11 +101,8 @@ fn setup_instructions(mut commands: Commands, asset_server: Res<AssetServer>) {
     )
     .with_style(Style {
         position_type: PositionType::Absolute,
-        position: UiRect {
-            bottom: Val::Px(10.0),
-            left: Val::Px(10.0),
-            ..default()
-        },
+        bottom: Val::Px(10.0),
+        left: Val::Px(10.0),
         ..default()
     }),));
 }
diff --git a/examples/3d/blend_modes.rs b/examples/3d/blend_modes.rs
index 5fe22dfc4a1776..458b5a6582ebc3 100644
--- a/examples/3d/blend_modes.rs
+++ b/examples/3d/blend_modes.rs
@@ -203,23 +203,16 @@ fn setup(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            top: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
 
     commands.spawn((
         TextBundle::from_section("", text_style).with_style(Style {
-            position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(10.0),
-                right: Val::Px(10.0),
-                ..default()
-            },
+            top: Val::Px(10.0),
+            right: Val::Px(10.0),
             ..default()
         }),
         ExampleDisplay,
@@ -365,8 +358,8 @@ fn example_control_system(
             .world_to_viewport(camera_global_transform, world_position)
             .unwrap();
 
-        style.position.bottom = Val::Px(viewport_position.y);
-        style.position.left = Val::Px(viewport_position.x);
+        style.bottom = Val::Px(viewport_position.y);
+        style.left = Val::Px(viewport_position.x);
     }
 
     let mut display = display.single_mut();
diff --git a/examples/3d/bloom_3d.rs b/examples/3d/bloom_3d.rs
index 94fcdf90fd7899..92688846d73b7b 100644
--- a/examples/3d/bloom_3d.rs
+++ b/examples/3d/bloom_3d.rs
@@ -106,11 +106,8 @@ fn setup_scene(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            bottom: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
diff --git a/examples/3d/fog.rs b/examples/3d/fog.rs
index 745b828982ddde..3e0c74861909d7 100644
--- a/examples/3d/fog.rs
+++ b/examples/3d/fog.rs
@@ -145,11 +145,8 @@ fn setup_instructions(mut commands: Commands, asset_server: Res<AssetServer>) {
     )
     .with_style(Style {
         position_type: PositionType::Absolute,
-        position: UiRect {
-            top: Val::Px(10.0),
-            left: Val::Px(10.0),
-            ..default()
-        },
+        top: Val::Px(10.0),
+        left: Val::Px(10.0),
         ..default()
     }),));
 }
diff --git a/examples/3d/pbr.rs b/examples/3d/pbr.rs
index ccf34966d975de..a6deda72708f1b 100644
--- a/examples/3d/pbr.rs
+++ b/examples/3d/pbr.rs
@@ -84,11 +84,8 @@ fn setup(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(20.0),
-                left: Val::Px(100.0),
-                ..default()
-            },
+            top: Val::Px(20.0),
+            left: Val::Px(100.0),
             ..default()
         }),
     );
@@ -104,11 +101,8 @@ fn setup(
         ),
         style: Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(130.0),
-                right: Val::Px(0.0),
-                ..default()
-            },
+            top: Val::Px(130.0),
+            right: Val::Px(0.0),
             ..default()
         },
         transform: Transform {
@@ -129,11 +123,8 @@ fn setup(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(20.0),
-                right: Val::Px(20.0),
-                ..default()
-            },
+            bottom: Val::Px(20.0),
+            right: Val::Px(20.0),
             ..default()
         }),
         EnvironmentMapLabel,
diff --git a/examples/3d/tonemapping.rs b/examples/3d/tonemapping.rs
index 996f6cbe14758a..81cd602b045786 100644
--- a/examples/3d/tonemapping.rs
+++ b/examples/3d/tonemapping.rs
@@ -76,11 +76,8 @@ fn setup(
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            top: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
diff --git a/examples/games/alien_cake_addict.rs b/examples/games/alien_cake_addict.rs
index 138186acaa46b8..7fbc2961c8a036 100644
--- a/examples/games/alien_cake_addict.rs
+++ b/examples/games/alien_cake_addict.rs
@@ -173,11 +173,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>, mut game: ResMu
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(5.0),
-                left: Val::Px(5.0),
-                ..default()
-            },
+            top: Val::Px(5.0),
+            left: Val::Px(5.0),
             ..default()
         }),
     );
diff --git a/examples/games/breakout.rs b/examples/games/breakout.rs
index bc308797fb3e5b..d74822872f6a31 100644
--- a/examples/games/breakout.rs
+++ b/examples/games/breakout.rs
@@ -240,11 +240,8 @@ fn setup(
         ])
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: SCOREBOARD_TEXT_PADDING,
-                left: SCOREBOARD_TEXT_PADDING,
-                ..default()
-            },
+            top: SCOREBOARD_TEXT_PADDING,
+            left: SCOREBOARD_TEXT_PADDING,
             ..default()
         }),
     );
diff --git a/examples/games/game_menu.rs b/examples/games/game_menu.rs
index 64710c5e2aee75..8dc39e701df44f 100644
--- a/examples/games/game_menu.rs
+++ b/examples/games/game_menu.rs
@@ -401,12 +401,8 @@ mod menu {
             // This takes the icons out of the flexbox flow, to be positioned exactly
             position_type: PositionType::Absolute,
             // The icon will be close to the left border of the button
-            position: UiRect {
-                left: Val::Px(10.0),
-                right: Val::Auto,
-                top: Val::Auto,
-                bottom: Val::Auto,
-            },
+            left: Val::Px(10.0),
+            right: Val::Auto,
             ..default()
         };
         let button_text_style = TextStyle {
diff --git a/examples/input/text_input.rs b/examples/input/text_input.rs
index 4263bfc42e6aa6..e083f76d255de1 100644
--- a/examples/input/text_input.rs
+++ b/examples/input/text_input.rs
@@ -78,11 +78,8 @@ fn setup_scene(mut commands: Commands, asset_server: Res<AssetServer>) {
         ])
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            top: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
diff --git a/examples/mobile/src/lib.rs b/examples/mobile/src/lib.rs
index 366c933162e813..66ae6696765df3 100644
--- a/examples/mobile/src/lib.rs
+++ b/examples/mobile/src/lib.rs
@@ -100,12 +100,10 @@ fn setup_scene(
                 justify_content: JustifyContent::Center,
                 align_items: AlignItems::Center,
                 position_type: PositionType::Absolute,
-                position: UiRect {
-                    left: Val::Px(50.0),
-                    right: Val::Px(50.0),
-                    top: Val::Auto,
-                    bottom: Val::Px(50.0),
-                },
+                left: Val::Px(50.0),
+                right: Val::Px(50.0),
+                top: Val::Auto,
+                bottom: Val::Px(50.0),
                 ..default()
             },
             ..default()
diff --git a/examples/shader/shader_prepass.rs b/examples/shader/shader_prepass.rs
index 9770d9f46a48e2..0271977128a45c 100644
--- a/examples/shader/shader_prepass.rs
+++ b/examples/shader/shader_prepass.rs
@@ -140,11 +140,8 @@ fn setup(
         ])
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(10.0),
-                left: Val::Px(10.0),
-                ..default()
-            },
+            top: Val::Px(10.0),
+            left: Val::Px(10.0),
             ..default()
         }),
     );
diff --git a/examples/stress_tests/bevymark.rs b/examples/stress_tests/bevymark.rs
index 876ef68fa54fe3..e4131e029fb7ad 100644
--- a/examples/stress_tests/bevymark.rs
+++ b/examples/stress_tests/bevymark.rs
@@ -121,11 +121,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
         ])
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(5.0),
-                left: Val::Px(5.0),
-                ..default()
-            },
+            top: Val::Px(5.0),
+            left: Val::Px(5.0),
             ..default()
         }),
         StatsText,
diff --git a/examples/stress_tests/many_buttons.rs b/examples/stress_tests/many_buttons.rs
index d39cfb38810e5e..826aa5395c2820 100644
--- a/examples/stress_tests/many_buttons.rs
+++ b/examples/stress_tests/many_buttons.rs
@@ -89,12 +89,8 @@ fn spawn_button(
             ButtonBundle {
                 style: Style {
                     size: Size::new(Val::Percent(width), Val::Percent(width)),
-
-                    position: UiRect {
-                        bottom: Val::Percent(100.0 / total * i as f32),
-                        left: Val::Percent(100.0 / total * j as f32),
-                        ..default()
-                    },
+                    bottom: Val::Percent(100.0 / total * i as f32),
+                    left: Val::Percent(100.0 / total * j as f32),
                     align_items: AlignItems::Center,
                     position_type: PositionType::Absolute,
                     ..default()
diff --git a/examples/ui/font_atlas_debug.rs b/examples/ui/font_atlas_debug.rs
index a732baca7c3668..0ca5596d243238 100644
--- a/examples/ui/font_atlas_debug.rs
+++ b/examples/ui/font_atlas_debug.rs
@@ -49,11 +49,8 @@ fn atlas_render_system(
                 image: texture_atlas.texture.clone().into(),
                 style: Style {
                     position_type: PositionType::Absolute,
-                    position: UiRect {
-                        top: Val::Px(0.0),
-                        left: Val::Px(512.0 * x_offset),
-                        ..default()
-                    },
+                    top: Val::Px(0.0),
+                    left: Val::Px(512.0 * x_offset),
                     ..default()
                 },
                 ..default()
@@ -85,10 +82,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>, mut state: ResM
             background_color: Color::NONE.into(),
             style: Style {
                 position_type: PositionType::Absolute,
-                position: UiRect {
-                    bottom: Val::Px(0.0),
-                    ..default()
-                },
+                bottom: Val::Px(0.0),
                 ..default()
             },
             ..default()
diff --git a/examples/ui/text.rs b/examples/ui/text.rs
index 3e73c847af3a96..607a204ec62a0a 100644
--- a/examples/ui/text.rs
+++ b/examples/ui/text.rs
@@ -43,11 +43,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
         // Set the style of the TextBundle itself.
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(5.0),
-                right: Val::Px(15.0),
-                ..default()
-            },
+            bottom: Val::Px(5.0),
+            right: Val::Px(15.0),
             ..default()
         }),
         ColorText,
diff --git a/examples/ui/text_debug.rs b/examples/ui/text_debug.rs
index 286558bcbbc00b..759ee88a669f48 100644
--- a/examples/ui/text_debug.rs
+++ b/examples/ui/text_debug.rs
@@ -37,11 +37,8 @@ fn infotext_system(mut commands: Commands, asset_server: Res<AssetServer>) {
         )
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(5.0),
-                left: Val::Px(15.0),
-                ..default()
-            },
+            top: Val::Px(5.0),
+            left: Val::Px(15.0),
             ..default()
         }),
     );
@@ -56,15 +53,9 @@ fn infotext_system(mut commands: Commands, asset_server: Res<AssetServer>) {
         .with_text_alignment(TextAlignment::Center)
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                top: Val::Px(5.0),
-                right: Val::Px(15.0),
-                ..default()
-            },
-            max_size: Size {
-                width: Val::Px(400.),
-                height: Val::Undefined,
-            },
+            top: Val::Px(5.0),
+            right: Val::Px(15.0),
+            max_size: Size::width(Val::Px(400.)),
             ..default()
         })
     );
@@ -115,11 +106,8 @@ fn infotext_system(mut commands: Commands, asset_server: Res<AssetServer>) {
         ])
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(5.0),
-                right: Val::Px(15.0),
-                ..default()
-            },
+            bottom: Val::Px(5.0),
+            right: Val::Px(15.0),
             ..default()
         }),
         TextChanges,
@@ -136,11 +124,8 @@ fn infotext_system(mut commands: Commands, asset_server: Res<AssetServer>) {
         .with_style(Style {
             align_self: AlignSelf::FlexEnd,
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(5.0),
-                left: Val::Px(15.0),
-                ..default()
-            },
+            bottom: Val::Px(5.0),
+            left: Val::Px(15.0),
             size: Size {
                 width: Val::Px(200.0),
                 ..default()
diff --git a/examples/ui/ui.rs b/examples/ui/ui.rs
index 954708c6335d97..827a75aa198ae5 100644
--- a/examples/ui/ui.rs
+++ b/examples/ui/ui.rs
@@ -27,7 +27,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
     commands
         .spawn(NodeBundle {
             style: Style {
-                size: Size::width(Val::Percent(100.0)),
+                size: Size::all(Val::Percent(100.)),
                 justify_content: JustifyContent::SpaceBetween,
                 ..default()
             },
@@ -38,8 +38,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
             parent
                 .spawn(NodeBundle {
                     style: Style {
-                        size: Size::width(Val::Px(200.0)),
-                        border: UiRect::all(Val::Px(2.0)),
+                        size: Size::width(Val::Px(200.)),
+                        border: UiRect::all(Val::Px(2.)),
                         ..default()
                     },
                     background_color: Color::rgb(0.65, 0.65, 0.65).into(),
@@ -50,7 +50,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                     parent
                         .spawn(NodeBundle {
                             style: Style {
-                                size: Size::width(Val::Percent(100.0)),
+                                size: Size::width(Val::Percent(100.)),
                                 ..default()
                             },
                             background_color: Color::rgb(0.15, 0.15, 0.15).into(),
@@ -68,7 +68,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                     },
                                 )
                                 .with_style(Style {
-                                    margin: UiRect::all(Val::Px(5.0)),
+                                    margin: UiRect::all(Val::Px(5.)),
                                     ..default()
                                 }),
                                 // Because this is a distinct label widget and
@@ -85,7 +85,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                         flex_direction: FlexDirection::Column,
                         justify_content: JustifyContent::Center,
                         align_items: AlignItems::Center,
-                        size: Size::width(Val::Px(200.0)),
+                        size: Size::width(Val::Px(200.)),
                         ..default()
                     },
                     background_color: Color::rgb(0.15, 0.15, 0.15).into(),
@@ -101,11 +101,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                 font_size: 25.,
                                 color: Color::WHITE,
                             },
-                        )
-                        .with_style(Style {
-                            size: Size::height(Val::Px(25.)),
-                            ..default()
-                        }),
+                        ),
                         Label,
                     ));
                     // List with hidden overflow
@@ -114,7 +110,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                             style: Style {
                                 flex_direction: FlexDirection::Column,
                                 align_self: AlignSelf::Stretch,
-                                size: Size::height(Val::Percent(50.0)),
+                                size: Size::height(Val::Percent(50.)),
                                 overflow: Overflow::Hidden,
                                 ..default()
                             },
@@ -129,7 +125,6 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                         style: Style {
                                             flex_direction: FlexDirection::Column,
                                             flex_grow: 1.0,
-                                            max_size: Size::UNDEFINED,
                                             align_items: AlignItems::Center,
                                             ..default()
                                         },
@@ -153,7 +148,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                             )
                                             .with_style(Style {
                                                 flex_shrink: 0.,
-                                                size: Size::new(Val::Undefined, Val::Px(20.)),
+                                                size: Size::height(Val::Px(20.)),
                                                 ..default()
                                             }),
                                             Label,
@@ -166,26 +161,23 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
             parent
                 .spawn(NodeBundle {
                     style: Style {
-                        size: Size::new(Val::Px(200.0), Val::Px(200.0)),
+                        size: Size::all(Val::Px(200.)),
                         position_type: PositionType::Absolute,
-                        position: UiRect {
-                            left: Val::Px(210.0),
-                            bottom: Val::Px(10.0),
-                            ..default()
-                        },
-                        border: UiRect::all(Val::Px(20.0)),
+                        left: Val::Px(210.),
+                        bottom: Val::Px(10.),
+                        border: UiRect::all(Val::Px(20.)),
                         ..default()
                     },
-                    background_color: Color::rgb(0.4, 0.4, 1.0).into(),
+                    background_color: Color::rgb(0.4, 0.4, 1.).into(),
                     ..default()
                 })
                 .with_children(|parent| {
                     parent.spawn(NodeBundle {
                         style: Style {
-                            size: Size::new(Val::Percent(100.0), Val::Percent(100.0)),
+                            size: Size::all(Val::Percent(100.)),
                             ..default()
                         },
-                        background_color: Color::rgb(0.8, 0.8, 1.0).into(),
+                        background_color: Color::rgb(0.8, 0.8, 1.).into(),
                         ..default()
                     });
                 });
@@ -193,7 +185,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
             parent
                 .spawn(NodeBundle {
                     style: Style {
-                        size: Size::new(Val::Percent(100.0), Val::Percent(100.0)),
+                        size: Size::all(Val::Percent(100.)),
                         position_type: PositionType::Absolute,
                         align_items: AlignItems::Center,
                         justify_content: JustifyContent::Center,
@@ -205,10 +197,10 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                     parent
                         .spawn(NodeBundle {
                             style: Style {
-                                size: Size::new(Val::Px(100.0), Val::Px(100.0)),
+                                size: Size::all(Val::Px(100.)),
                                 ..default()
                             },
-                            background_color: Color::rgb(1.0, 0.0, 0.0).into(),
+                            background_color: Color::rgb(1.0, 0.0, 0.).into(),
                             ..default()
                         })
                         .with_children(|parent| {
@@ -217,11 +209,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                     // Take the size of the parent node.
                                     size: Size::all(Val::Percent(100.)),
                                     position_type: PositionType::Absolute,
-                                    position: UiRect {
-                                        left: Val::Px(20.0),
-                                        bottom: Val::Px(20.0),
-                                        ..default()
-                                    },
+                                    left: Val::Px(20.),
+                                    bottom: Val::Px(20.),
                                     ..default()
                                 },
                                 background_color: Color::rgb(1.0, 0.3, 0.3).into(),
@@ -231,11 +220,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                 style: Style {
                                     size: Size::all(Val::Percent(100.)),
                                     position_type: PositionType::Absolute,
-                                    position: UiRect {
-                                        left: Val::Px(40.0),
-                                        bottom: Val::Px(40.0),
-                                        ..default()
-                                    },
+                                    left: Val::Px(40.),
+                                    bottom: Val::Px(40.),
                                     ..default()
                                 },
                                 background_color: Color::rgb(1.0, 0.5, 0.5).into(),
@@ -245,11 +231,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                 style: Style {
                                     size: Size::all(Val::Percent(100.)),
                                     position_type: PositionType::Absolute,
-                                    position: UiRect {
-                                        left: Val::Px(60.0),
-                                        bottom: Val::Px(60.0),
-                                        ..default()
-                                    },
+                                    left: Val::Px(60.),
+                                    bottom: Val::Px(60.),
                                     ..default()
                                 },
                                 background_color: Color::rgb(1.0, 0.7, 0.7).into(),
@@ -260,11 +243,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                                 style: Style {
                                     size: Size::all(Val::Percent(100.)),
                                     position_type: PositionType::Absolute,
-                                    position: UiRect {
-                                        left: Val::Px(80.0),
-                                        bottom: Val::Px(80.0),
-                                        ..default()
-                                    },
+                                    left: Val::Px(80.),
+                                    bottom: Val::Px(80.),
                                     ..default()
                                 },
                                 background_color: Color::rgba(1.0, 0.9, 0.9, 0.4).into(),
@@ -286,6 +266,7 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
                 })
                 .with_children(|parent| {
                     // bevy logo (image)
+
                     parent
                         .spawn(ImageBundle {
                             style: Style {
@@ -327,7 +308,7 @@ fn mouse_scroll(
             };
             scrolling_list.position += dy;
             scrolling_list.position = scrolling_list.position.clamp(-max_scroll, 0.);
-            style.position.top = Val::Px(scrolling_list.position);
+            style.top = Val::Px(scrolling_list.position);
         }
     }
 }
diff --git a/examples/ui/ui_scaling.rs b/examples/ui/ui_scaling.rs
index 877857a3528674..d9a0adbbb1adc6 100644
--- a/examples/ui/ui_scaling.rs
+++ b/examples/ui/ui_scaling.rs
@@ -38,11 +38,8 @@ fn setup(mut commands: Commands, asset_server: ResMut<AssetServer>) {
             style: Style {
                 size: Size::new(Val::Percent(50.0), Val::Percent(50.0)),
                 position_type: PositionType::Absolute,
-                position: UiRect {
-                    left: Val::Percent(25.),
-                    top: Val::Percent(25.),
-                    ..default()
-                },
+                left: Val::Percent(25.),
+                top: Val::Percent(25.),
                 justify_content: JustifyContent::SpaceAround,
                 align_items: AlignItems::Center,
                 ..default()
diff --git a/examples/ui/window_fallthrough.rs b/examples/ui/window_fallthrough.rs
index 123b40b41d50ba..21c00cfd33621c 100644
--- a/examples/ui/window_fallthrough.rs
+++ b/examples/ui/window_fallthrough.rs
@@ -40,11 +40,8 @@ fn setup(mut commands: Commands, asset_server: Res<AssetServer>) {
         // Set the style of the TextBundle itself.
         .with_style(Style {
             position_type: PositionType::Absolute,
-            position: UiRect {
-                bottom: Val::Px(5.),
-                right: Val::Px(10.),
-                ..default()
-            },
+            bottom: Val::Px(5.),
+            right: Val::Px(10.),
             ..default()
         }),
     ));
diff --git a/examples/ui/z_index.rs b/examples/ui/z_index.rs
index 08a51b0a68060e..05d6e9c77b3b2b 100644
--- a/examples/ui/z_index.rs
+++ b/examples/ui/z_index.rs
@@ -45,11 +45,8 @@ fn setup(mut commands: Commands) {
                         background_color: Color::RED.into(),
                         style: Style {
                             position_type: PositionType::Absolute,
-                            position: UiRect {
-                                left: Val::Px(10.0),
-                                bottom: Val::Px(40.0),
-                                ..default()
-                            },
+                            left: Val::Px(10.0),
+                            bottom: Val::Px(40.0),
                             size: Size::new(Val::Px(100.0), Val::Px(50.0)),
                             ..default()
                         },
@@ -63,11 +60,8 @@ fn setup(mut commands: Commands) {
                         background_color: Color::BLUE.into(),
                         style: Style {
                             position_type: PositionType::Absolute,
-                            position: UiRect {
-                                left: Val::Px(45.0),
-                                bottom: Val::Px(30.0),
-                                ..default()
-                            },
+                            left: Val::Px(45.0),
+                            bottom: Val::Px(30.0),
                             size: Size::new(Val::Px(100.0), Val::Px(50.0)),
                             ..default()
                         },
@@ -81,11 +75,8 @@ fn setup(mut commands: Commands) {
                         background_color: Color::GREEN.into(),
                         style: Style {
                             position_type: PositionType::Absolute,
-                            position: UiRect {
-                                left: Val::Px(70.0),
-                                bottom: Val::Px(20.0),
-                                ..default()
-                            },
+                            left: Val::Px(70.0),
+                            bottom: Val::Px(20.0),
                             size: Size::new(Val::Px(100.0), Val::Px(75.0)),
                             ..default()
                         },
@@ -100,11 +91,8 @@ fn setup(mut commands: Commands) {
                         background_color: Color::PURPLE.into(),
                         style: Style {
                             position_type: PositionType::Absolute,
-                            position: UiRect {
-                                left: Val::Px(15.0),
-                                bottom: Val::Px(10.0),
-                                ..default()
-                            },
+                            left: Val::Px(15.0),
+                            bottom: Val::Px(10.0),
                             size: Size::new(Val::Px(100.0), Val::Px(60.0)),
                             ..default()
                         },
@@ -119,11 +107,8 @@ fn setup(mut commands: Commands) {
                         background_color: Color::YELLOW.into(),
                         style: Style {
                             position_type: PositionType::Absolute,
-                            position: UiRect {
-                                left: Val::Px(-15.0),
-                                bottom: Val::Px(-15.0),
-                                ..default()
-                            },
+                            left: Val::Px(-15.0),
+                            bottom: Val::Px(-15.0),
                             size: Size::new(Val::Px(100.0), Val::Px(125.0)),
                             ..default()
                         },
diff --git a/examples/window/low_power.rs b/examples/window/low_power.rs
index f57183cc8be368..8a457cbd0b08bf 100644
--- a/examples/window/low_power.rs
+++ b/examples/window/low_power.rs
@@ -201,11 +201,8 @@ pub(crate) mod test_setup {
             .with_style(Style {
                 align_self: AlignSelf::FlexStart,
                 position_type: PositionType::Absolute,
-                position: UiRect {
-                    top: Val::Px(5.0),
-                    left: Val::Px(5.0),
-                    ..default()
-                },
+                top: Val::Px(5.0),
+                left: Val::Px(5.0),
                 ..default()
             }),
             ModeText,