In the opening application tag of my Flex 4 app, I set the width and height properties as follows:

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
           xmlns:s="library://ns.adobe.com/flex/spark"
           xmlns:mx="library://ns.adobe.com/flex/mx"
           creationComplete="init()"
           backgroundColor.mainState="0x303030"
           xmlns:components="components.*"
           width="798"
           height="240">

What I go into Design mode in Flash Builder 4, the app is the correct size. But when I embed the .swf file into a HTML page, the application's background color covers the whole screen, and when the Flash Player Settings message box pops up it is outside of the area I defined in the code above. What am I doing wrong? Thanks for reading.