less伪类（更多）
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link rel="stylesheet/less" type="text/css" href="css/demo2.css">
<script src="js/less.js"></script>
</head>
<body>
<div class="wrap">
<div class="header">
头部
<a href="">更多</a>
</div>
<div class="content">
<div class="left">左边</div>
<div class="right">右边</div>
</div>
</div>
</body>
</html>
