<!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>无标题文档</title>
<style type="text/css">
*{margin:0; padding:0;}
#wrap{background:#00C; margin:0 auto; width:960px;}
#header{ background; #FF3300; width:100%;}
#mainbody{background:#FC0; width:100%; overflow:hidden}
.left{width:800px; height:200px; background:#000; float:left; margin-right:20px;}
.right{width:140px; height:500px; background:#690; float:left;}
#footer{background:#639; width:100%;}
</style>
</head>
<body>
<div id="wrap">
<div id="header">header</div>
<div id="mainbody">mainbody
<div class="left">left</div>
<div class="right">right</div>
</div>
<div id="footer">版权部分</div>
</div>
</body>
</html>
老师我按照课程来编写,为什么是这个状态
