stack & padding fix sorta, preparing for scroll areas

src/layout/pos.rs

@@ -100,9 +100,7 @@ impl UiVec2 {
         self.rel * size + self.abs
     }
 
-    pub const fn max_size() -> Self {
-        Self::rel(Vec2::ONE)
-    }
+    pub const MAX_SIZE: Self = Self::rel(Vec2::ONE);
 
     pub const fn from_axis(axis: Axis, aligned: UiScalar, ortho: UiScalar) -> Self {
         Self {
@@ -134,6 +132,8 @@ impl_op!(UiScalar Add add; rel abs);
 impl_op!(UiScalar Sub sub; rel abs);
 
 impl UiScalar {
+    pub const ZERO: Self = Self { rel: 0.0, abs: 0.0 };
+
     pub fn new(rel: f32, abs: f32) -> Self {
         Self { rel, abs }
     }