<?xml version="1.0" encoding="utf-8"?>
<!-- http://blog.flexexamples.com/2008/10/19/toggling-the-drop-shadow-on-a-panel-container-in-flex/ -->
<mx:Application name="Panel_dropShadowEnabled_test"
        xmlns:mx="http://www.adobe.com/2006/mxml"
        layout="vertical"
        verticalAlign="middle"
        backgroundColor="white">
    
    <mx:Style>
        Panel {
            border-color: haloSilver;
            dropShadowEnabled: false;
        }
    </mx:Style>

    <mx:Panel id="panel"
            title="Panel title"
            width="100%"
            height="100%">
        <mx:Label text="Panel contents" />
    </mx:Panel>

</mx:Application>