手机站，纯全屏，1rem=100px

<!DOCTYPE html>
<html>
<head>
   <script type="text/javascript">
   document.documentElement.style.fontSize=document.documentElement.clientWidth/6.4+'px';
   document.documentElement.style.fontSize=document.documentElement.clientWidth/6.4+'px';;
   </script>
</head>
<body>
</body>
</html>