<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>三列布局_左右固定_中间自适应</title>
<style>
.left{
200px;
height: 600px;
background-color: #008B8B;
float: left;
}
.right{
200px;
height: 600px;
background-color: #FFFF00;
float: right;
}
.main{
height: 600px;
margin-left: 200px;
margin-right: 200px;
background-color: #4169E1;
}
</style>
</head>
<body>
<h2>基本思路</h2>
<ol>
<li>和2列布局很相似</li>
<li>左右2列采用浮动+宽度</li>
<li>中间区域实际是用margin挤压出来的</li>
<li>DOM顺序不能写乱，必须先写左右再写中间</li>
</ol>
<!-- DOM -->
<div class="left">左侧</div>
<div class="right">右侧</div>
<div class="main">主体</div>
</body>
</html>