diff --git a/ui.odin b/ui.odin
index 1dc42b2..859bd66 100644
--- a/ui.odin
+++ b/ui.odin
@@ -3,8 +3,13 @@ package synthas_ui
 v2 :: [2]f32
 rect2 :: struct {x, y, width, height: f32}
 
-@private rect_get_bl :: proc(rect: rect2) -> v2 {
-	return {rect.x, rect.y + rect.height}
+@private rect_get_tl :: #force_inline proc(rect: rect2) -> v2 {return {rect.x, rect.y}}
+@private rect_get_tr :: #force_inline proc(rect: rect2) -> v2 {return {rect.x + rect.width, rect.y}}
+@private rect_get_br :: #force_inline proc(rect: rect2) -> v2 {return {rect.x + rect.width, rect.y + rect.height}}
+@private rect_get_bl :: #force_inline proc(rect: rect2) -> v2 {return {rect.x, rect.y + rect.height}}
+
+@private rect_grow :: proc(rect: rect2, amount: v2) -> rect2 {
+	return {rect.x - amount.x / 2.0, rect.y - amount.y / 2.0, rect.width + amount.x, rect.height + amount.y}
 }
 
 @private ctx: ^Context
@@ -26,6 +31,7 @@ Element :: struct {
 	label: cstring,
 	color: [4]u8,
 	data: ElementData,
+	margin, padding: v2,
 }
 
 ElementData :: union {
@@ -67,16 +73,26 @@ same_line :: proc() {
 	ctx.same_line = true
 }
 
+element_get_outer_area :: proc(element: Element) -> rect2 {
+	return rect_grow(element.area, element.margin * 2.0)
+}
+
+element_get_inner_area :: proc(element: Element) -> rect2 {
+	return rect_grow(element.area, -element.padding * 2.0)
+}
+
 ElementData_Container :: struct {
 	margin, padding: v2,
 }
 
 container_begin :: proc(dimensions: Dimensions, margin: v2, padding: v2, label: cstring, color: [4]u8) {
 	ctx.container_position += margin
-	area := rect2{**ctx.container_position, **_resolve_dimensions(dimensions)}
-	ctx.element_position = ctx.container_position + padding
+	size := _resolve_dimensions(dimensions) - margin * 2.0
+	area := rect2{**ctx.container_position, **size}
+	ctx.container_position += padding
+	ctx.element_position = ctx.container_position
 	data := ElementData_Container {margin = margin, padding = padding}
-	element := Element{area = area, color = color, label = label, data = data}
+	element := Element{area = area, color = color, label = label, data = data, margin = margin, padding = padding}
 	append(&ctx.elements, element)
 	container := _element_last()
 	append(&ctx.container_stack, container)
@@ -111,7 +127,8 @@ _resolve_size :: proc(size: Size, axis: Axis) -> f32 {
 		return cast(f32)value
 	case Size_Percentage:
 		if container := _container_last(); container != nil {
-			container_size := container.area.width if axis == .X else container.area.height
+			inner := element_get_inner_area(container^)
+			container_size := inner.width if axis == .X else inner.height
 			return container_size * cast(f32)value
 		} else {
 			panic("Cannot use dimension Size_Percentage without an outer container")