用一段代码来显示：
<!doctype html>
<html>
<head>
<meta charset=utf-8>
<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
<!--[if lt IE 9]>
<script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
<script src="https://oss.maxcdn.com/libs/respond.js/1.3.0/respond.min.js"></script>
<![endif]-->
<meta http-equiv="X-UA-Compatible" content="IE=Edge，chrome=1">
</head>
<body>
<style type=text/css>
/*当浏览器尺寸小于960px时候的代码：*/
@media screen and (max-width:960px){
body{
background:green;
}
}
/*当浏览器尺寸等于960px时候的代码：*/
@media screen and (max-device-width:960px){
body{
background:red;
}
}
/*当浏览器尺寸大于960px时候的代码：*/
@media screen and (min-width:960px){
body{
background:blue;
}
}
/*混合使用上面的用法：
@media screen and (min-width:960px) and (max-width:1200px){
body{
background:yellow;
}
}*/
</style>
</body>
</html>