<style type="text/css">
div{background:#ddd;border:1px solid #000;width:400px;}
.box{overflow:auto;zoom:1;}/*zoom:IE 6,7*/ 
img{float:right;} </style>
<h1>清除浮动</h1>
<div class="box"><img src="http://zh.learnlayout.com/images/ilta.png"></div>
<br><br>
<div><img src="http://zh.learnlayout.com/images/ilta.png"></div>

<style type="text/css">
div{background:#999;width: 500px;height:100px;margin: 20px;}
.simple {
  -webkit-box-sizing: border-box;
     -moz-box-sizing: border-box;
          box-sizing: border-box;
}
.fancy {
  padding: 50px;
  border: solid #000 20px;
  -webkit-box-sizing: border-box;
     -moz-box-sizing: border-box;
          box-sizing: border-box;
}
.ccc{
  border: solid #000 20px;
}
</style>
<h1>box-sizing : IE8及IE8+</h1>
<div class="simple">aaaaaaaa</div>
<div class="fancy">aaaaaaaaa</div>
<div class="ccc">aaaaaaaaa</div>