媒体查询

@media screen and (max-width:800px){ }

@media screen and (max-width: 600px){
            .list{
                width: 100%;
                height: 100px;
            }
            
}

meta:

<meta name="keywords" content="关键字">
<meta name="description" content="你的网页的内容">

viewport (视窗) ：设置视窗布局

<meta name=”viewport” content=”width=device-width,initial-scale=1″ />

width：控制 viewport 的大小，可以指定的一个值，如 600，或者特殊的值，如 device-width 为设备的宽度（单位为缩放为 100% 时的 CSS 的像素）；
height：和 width 相对应，指定高度；
initial-scale：初始缩放比例，也即是当页面第一次 load 的时候缩放比例；
maximum-scale：允许用户缩放到的最大比例；
minimum-scale：允许用户缩放到的最小比例；
user-scalable：用户是否可以手动缩放，值为"yes"或"no"。

<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no" />

em和rem

em 一个文字的倍数
继承父级元素的字体大小
rem 一个文字的倍数
继承根目录的字体大小

px自动转换成rem网站：
http://mxd.tencent.com/wp-content/uploads/2014/11/rem.html

media-100.css:

<link rel='stylesheet' href='css/media-100.css'>

    @media only screen and (min-width: 1080px), only screen and (min-device-width:1080px) {
     html,body {
         font-size:168.75px;
     }
   }



   @media only screen and (max-width: 1080px), only screen and (max-device-width:1080px) {
     html,body {
         font-size:168.75px;
     }
   }
     @media only screen and (max-width: 960px), only screen and (max-device-width:960px) {
     html,body {
         font-size:150px;
     }
   }
     @media only screen and (max-width: 800px), only screen and (max-device-width:800px) {
     html,body {
         font-size:125px;
     }
   }
     @media only screen and (max-width: 720px), only screen and (max-device-width:720px) {
     html,body {
         font-size:112.5px;
     }
   }
     @media only screen and (max-width: 640px), only screen and (max-device-width:640px) {
     html,body {
         font-size:100px;
     }
   }
     @media only screen and (max-width: 600px), only screen and (max-device-width:600px) {
     html,body {
         font-size:93.75px;
     }
   }
     @media only screen and (max-width: 540px), only screen and (max-device-width:540px) {
     html,body {
         font-size:84.375px;
     }
   }
     @media only screen and (max-width: 480px), only screen and (max-device-width:480px) {
     html,body {
         font-size:75px;
     }
   }
     @media only screen and (max-width: 414px), only screen and (max-device-width:414px) {
     html,body {
         font-size:64.6875px;
     }
   }
     @media only screen and (max-width: 400px), only screen and (max-device-width:400px) {
     html,body {
         font-size:62.5px;
     }
   }
     @media only screen and (max-width: 375px), only screen and (max-device-width:375px) {
     html,body {
         font-size:58.59375px;
     }
   }
     @media only screen and (max-width: 360px), only screen and (max-device-width:360px) {
     html,body {
         font-size:56.25px;
     }
   }
     @media only screen and (max-width: 320px), only screen and (max-device-width:320px) {
     html,body {
         font-size:50px;
     }
   }
     @media only screen and (max-width: 240px), only screen and (max-device-width:240px) {
     html,body {
         font-size:37.5px;
     }
   }