/*可以解决选中时蓝色背景*/
-webkit-user-select: none;
-moz-user-select: none;
-ms-user-select: none;
user-select: none;
--DIV不会被内部撑大可以设置 :box-sizing:padding-box;
-- 流式布局:
<meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0,user-scalable=no" id="viewport">
<title>流式布局</title>
<link rel="stylesheet" type="text/css" href="css/1.css" media="(max-750px)">
<link rel="stylesheet" type="text/css" href="css/2.css" media="(min-751px)">
<link rel="stylesheet" type="text/css" href="css/2.css" media="(max-450px)">