求大神错在哪里
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>混合布局编程挑战</title>
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; background::#fff}
.top{width:100%;height:100px; background:#30C}
.main{width:100%;height:600px;background:#00F; position:absolute}
.left{ width:200px;height:600px;background:#3CC; position:absolute;top:0; left:0}
.right{width:80%;height:600px;background:#F33; margin-left:210px}
.foot{width:100px;height:100px; background:#939; clear:both;}
</style>
</head>
<body>
<div class="top">top</div>
<div class="main">
<div class="right">right</div>
<div class="left">left</div>
</div>
<div class="foot">foot</div>
</body>
</html>
