diff --git a/flumi/Scripts/Engine/StyleManager.gd b/flumi/Scripts/Engine/StyleManager.gd
index 7cad2c0..9c96e8c 100644
--- a/flumi/Scripts/Engine/StyleManager.gd
+++ b/flumi/Scripts/Engine/StyleManager.gd
@@ -68,13 +68,18 @@ static func apply_element_styles(node: Control, element: HTMLParser.HTMLElement,
 				if width == "100%":
 					node.size_flags_horizontal = Control.SIZE_EXPAND_FILL
 					node.custom_minimum_size.x = 0
+					if node is PanelContainer and node.get_child_count() > 0:
+						var vbox = node.get_child(0)
+						if vbox is VBoxContainer:
+							vbox.size_flags_horizontal = Control.SIZE_EXPAND_FILL
+					node.set_meta("size_flags_set_by_style_manager", true)
 				else:
 					# For other percentages, convert to viewport-relative size
 					var percent = float(width.replace("%", "")) / 100.0
 					var viewport_width = node.get_viewport().get_visible_rect().size.x if node.get_viewport() else 800
 					node.custom_minimum_size.x = viewport_width * percent
-				node.set_meta("size_flags_set_by_style_manager", true)
-				node.size_flags_horizontal = Control.SIZE_SHRINK_BEGIN
+					node.set_meta("size_flags_set_by_style_manager", true)
+					node.size_flags_horizontal = Control.SIZE_SHRINK_BEGIN
 			else:
 				node.custom_minimum_size.x = width
 				node.size_flags_horizontal = Control.SIZE_SHRINK_BEGIN