如题所述
第1个回答 2015-02-08
里面div高度设置成自动，外面的设置一个 最小高度就行了
第2个回答 推荐于2016-07-22
清除浮动 在最后一个div 后面加上 这句话
<div style="clear:both;height:1px;width:100%; overflow:hidden; margin-top:-1px;"></div>
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<body>
<div style="width:580px; height:auto; margin:0 auto; background-color:#333">
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="clear:both;height:1px;width:100%; overflow:hidden; margin-top:-1px;"></div>
</div>
</body>本回答被提问者和网友采纳
<div style="clear:both;height:1px;width:100%; overflow:hidden; margin-top:-1px;"></div>
--------------------------------------------------------------------------------------------------------------------
<body>
<div style="width:580px; height:auto; margin:0 auto; background-color:#333">
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="height:100px; width:230px; float:left; background-color:#CCC; margin:20px"></div>
<div style="clear:both;height:1px;width:100%; overflow:hidden; margin-top:-1px;"></div>
</div>
</body>本回答被提问者和网友采纳
