Mine

/index.mxml
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<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" 
	xmlns:home="comp.home.*"
	xmlns:news="comp.news.*"
	layout="absolute" 
	backgroundImage="@Embed('assets/back.jpg')">

    <mx:Style source="css/main.css"/>
    
    <mx:Image x="10" y="10" source="@Embed('assets/logo.png')"/>
    
    <mx:ApplicationControlBar y="85" height="27" paddingTop="0" left="10" right="10">
	<mx:LinkBar dataProvider="storeViews" disabledColor="#ffffff"/>
    </mx:ApplicationControlBar>

    <mx:VBox width="100%" paddingLeft="0" paddingRight="0" top="115" height="100%">

        <mx:ViewStack id="storeViews" width="100%" height="100%" creationPolicy="all">
			<home:home label="home"/>
			<news:news label="news"/>
        </mx:ViewStack>

    </mx:VBox>

</mx:Application>

========================================================================

/comp/home/home.mxml
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<?xml version="1.0" encoding="utf-8"?>
<mx:Canvas xmlns:mx="http://www.adobe.com/2006/mxml" width="100%" height="100%" backgroundColor="#0080ff" styleName="views">
    <mx:HBox left="10" top="10" right="10" bottom="10">
    </mx:HBox>
</mx:Canvas>

========================================================================

/css/main.css
------------------------------------------------------------------------

.views {
	background-color: #FFFFFF;  
}

========================================================================