diff --git a/lib/cyberarm_engine/ui/container.rb b/lib/cyberarm_engine/ui/container.rb
index 7854647..1fa43ab 100644
--- a/lib/cyberarm_engine/ui/container.rb
+++ b/lib/cyberarm_engine/ui/container.rb
@@ -60,8 +60,13 @@ module CyberarmEngine
 
       layout
 
-      @style.width  = @max_width  ? @max_width  : (@children.map {|c| c.x + c.outer_width }.max || 0).round
-      @style.height = @max_height ? @max_height : (@children.map {|c| c.y + c.outer_height}.max || 0).round
+      if is_root?
+        @style.width  = window.width
+        @style.height = window.height
+      else
+        @style.width  = @max_width  ? @max_width  : (@children.map {|c| c.x + c.outer_width }.max || 0).round
+        @style.height = @max_height ? @max_height : (@children.map {|c| c.y + c.outer_height}.max || 0).round
+      end
 
       # Move child to parent after positioning
       @children.each do |child|
diff --git a/lib/cyberarm_engine/ui/element.rb b/lib/cyberarm_engine/ui/element.rb
index 4fe7f0f..8af35fd 100644
--- a/lib/cyberarm_engine/ui/element.rb
+++ b/lib/cyberarm_engine/ui/element.rb
@@ -214,6 +214,10 @@ module CyberarmEngine
       @root
     end
 
+    def is_root?
+      @gui_state != nil
+    end
+
     def recalculate
       raise "#{self.class}#recalculate was not overridden!"
     end