Apply dropShadowEnabled to CSS
<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:Style> @namespace mx "http://www.adobe.com/2006/mxml"; mx|VBox { backgroundColor: green; borderStyle: solid; dropShadowEnabled: 1; } </mx:Style> <mx:VBox width="200" height="200"/> </mx:Application>