<link href="xiangyingshi.css" type="text/css" rel="stylesheet" media="only screen and(max-width:640px)" />//最大不能超过640px
<style>
@media screen and (min-width:640px){//最小不能小于640px
body{
background-color:#003;}
}
</style>
<body>
</body>
</html>
<meta name="viewport" content="width=device-width,initial-scale=1" />//content="width=device-width指定设备的宽，initial-scale=1按照原比例进行缩放
@media screen and (min-width: 600px;) and (max-width: 960px){}//最小600最大960px；
原文：http://www.cnblogs.com/-chengkai/p/4702689.html