<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
.top {
margin: 0 auto;
width: 1000px;
/* height: 300px; */
background-color: pink;
}
.bottom {
height: 100px;
background-color: green;
}
.left {
float: left;
width: 200px;
height: 300px;
background-color: #ccc;
}
.right {
float: right;
width: 790px;
height: 300px;
background-color: skyblue;
}
/* 单伪元素清除浮动 和 额外标签法原理是一样的 */
.clearfix::after {
content: '';
/* 伪元素添加的标签是行内, 要求块 */
display: block;
clear: both;
/* 为了兼容性 */
height: 0;
visibility: hidden;
}
</style>
</head>
<body>
<!-- 父子级标签, 子级浮动, 父级没有高度, 后面的标准流盒子会受影响, 显示到上面的位置 -->
<div class="top clearfix">
<div class="left"></div>
<div class="right"></div>
<!-- 通过css 添加标签 -->
</div>
<div class="bottom"></div>
</body>
</html>
