1.定高法 :给父级容器添加高度
<style> .contain{ width: 500px; /* 给父级容器添加高 */ height: 500px; border: 1px solid #000; } .box{ width: 300px; height: 300px; background-color: red; float: left; } </style> <div class="contain"> <div class="box"></div> </div>
2.额外标签法:在浮动元素的后边添加一个块级标签,这个标签专门clear:both
<style> .contain{ width: 500px; border: 1px solid #000; } .box{ width: 300px; height: 300px; background-color: red; float: left; } .clear{ clear: both; } </style> <div class="contain"> <div class="box"></div> <div class="clear"></div> </div>
原文:https://www.cnblogs.com/zhaodz/p/11573904.html