utf-8编码
<mata charset="utf-8">
兼容IE浏览器
<meta http-equiv="X-UA-Compatible" content="IE=edge">
兼容IE 9 以下版本的插件
HTML5:
<script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/htnl5shiv.js"></script>
CSS 3样式：
<script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
媒体查询：
<meta name="viewport" content="width=device-width,initial-scale=1">
