宿題|余白が15pxのfloat

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "/W3C//DTD XHTML1.0 Strict//EN" "http//www.w3.org/TR/xhtml/DTD/xhtml1-strict.dtd">
<html xmls="http://www.w3/org/1999/xhtml" lang="ja"xml:lang="ja">
<head>
<meta http-equiv="Content-Style-Type" content="text/html;charset=UTF-8" />
<meta http-equiv="Content-Style-Type" content="text/xss" />
<title>10/3 TEST2</title>
<style type="text/css">
<!--
*{
    margin: 0;
	padding: 0;
}
body{
    background-color:  #d2e5e5;
}
#container{
    width: 800px;
	height: auto;
	margin: 15px auto;
	padding: 15px 0;
	background-color: #ffffff;
}
#header{
    width: 770px;
	height: 85px;
	margin: 0 15px 15px 15px;
	background-color: #cbc2eb;
}
#wrapper{
    width: 800px;
	height: auto;
    margin: 0 0 15px 0 ;
	overflow: auto;
}
#content{
    width: 525px;
	height: 350px;
	margin: 0 0 0 15px;
	float: left;
	background-color: #ffefd5;
}
#sidebar{
    width: 230px;
	height: 350px;
	margin: 0 15px 0 0;
	background-color: #ccffcc;
	float: right;
}
#footer{
    width: 770px;
	height: 85px;
	margin: 0 15px 0 15px;
	background-color: #f0e68c;
	clear: both;
}
-->
</style>
</head>
<body>
<div id="container">
	<div id="header">header</div>
	<div id="wrapper">
		<div id="content">content</div>
		<div id="sidebar">sidebar</div>
	</div>
	<div id="footer">footer</div>
</div>
</body>
</html>