三栏格局
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh" lang="zh">
<head profile="http://www.w3.org/2000/08/w3c-synd/#">
<meta http-equiv="content-language" content="zh-cn" />
<meta http-equiv="content-type" content="text/html;charset=gb2312" />
<title>blueidea</title>
<style type="text/css">
/*<![CDATA[*/
div {
position:absolute;
top:50%;
left:50%;
margin:-100px 0 0 -300px;
}
/*]]>*/
</style>
</head>
<body>
<div style="background:#404040;200px;height:200px;">1</div>
<div style="background:#FD7C03;200px;height:200px;margin:-100px 0 0 -100px;">2</div>
<div style="background:#eee;200px;height:200px;margin:-100px 0 0 100px;">3</div>
</body>
</html>