//必须先加载此meta
<meta name="viewport" content="initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
//共同的css样式
<link rel="stylesheet" href="./css/common.css" />
//指大于500px宽度时调用desktop.css样式
<link media="(min-width:500px)" rel="stylesheet" href="./css/desktop.css" />
//指小于500px时调用mobile.css样式
<link media="(max-width:500px)" rel="stylesheet" href="./css/mobile.css" />
css注意
1个css的像素=2个物理像素
demo
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />
<title></title>
<link rel="stylesheet" href="./css/common.css" />
<link media="(min-width:500px)" rel="stylesheet" href="./css/desktop.css" />
<link media="(max-width:500px)" rel="stylesheet" href="./css/mobile.css" />
<style>
/* checkbox自带的伪类*/
#checkd:checked ~ p{
display: none;
}
#checkd{
display: none;
}
</style>
</head>
<body>
<!--for属性绑定对应的id,表示绑定作用-->
<label for="checkd">菜单</label>
<input id="checkd" type="checkbox" />
<p>aaaa</p>
</body>
</html>