它主要是采用“隐藏容器溢出”和“正内补丁”和“负外补丁”结合方式，示例代码如下：
<!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>Div + CSS Example, Wayhome's Blog</title>
<style type="text/css">
<!--
#wrap{overflow:hidden;}
#sidebar_left,#sidebar_right{padding-bottom:100000px;margin-bottom:-100000px;}
-->
</style></head>
<body>
<div id="wrap" style="300px; background:#FFFF00;">
<div id="sidebar_left" style="float:left;100px; background:#FF0000;">Left</div>
<div id="sidebar_mid" style="float:left;100px; background:#666;">
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
</div>
<div id="sidebar_right" style="float:right;100px; background:#0000FF;">Right</div>
</div>
</body>
</html>
<html XMLns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Div + CSS Example, Wayhome's Blog</title>
<style type="text/css">
<!--
#wrap{overflow:hidden;}
#sidebar_left,#sidebar_right{padding-bottom:100000px;margin-bottom:-100000px;}
-->
</style></head>
<body>
<div id="wrap" style="300px; background:#FFFF00;">
<div id="sidebar_left" style="float:left;100px; background:#FF0000;">Left</div>
<div id="sidebar_mid" style="float:left;100px; background:#666;">
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
Middle<br />
</div>
<div id="sidebar_right" style="float:right;100px; background:#0000FF;">Right</div>
</div>
</body>
</html>