<!DOCTYPE html>
<html>
    <head>
        <meta charset=utf-8>
        <style type="text/css">
            * {
                margin: 0;
                padding: 0;
                width:300px;
            }
            .left{
                height:120px;
                width:120px;
                float:left;
                background:red;
            }
            .center{
                height:100px;
                width:100px;
                float:left;
                background:green;
            }
            .right{
                height:100px;
                width:100px;
                float:left;
                background:blue;
            }
        </style>
    </head>
    <body>
    	<div class="left"></div>
        <div class="center"></div>
        <div class="right"></div>
    </body>
</html>

小萌新的题解。

考察：

  1. 浮动的特性