.lizi:after{
content: "I'M after"; /*插入字符串*/
content: "attr(id)"; /*插入当前元素属性*/
content: url(/path/to/image.jpg); /*插入图片*/
content: counter(li); /*插入计数器*/
content: ""; /*啥也不插*/
}
1 <div class="triangle">
2 <input type="text">
3 </div>
4 <style type="text/css">
5 .triangle input{
6 height: 30px;
7 width: 200px;
8 border-radius: 4px;
9 border: 1px solid #ccc;
10 }
11 .triangle{
12 width: 200px;
13 position: relative;
14 }
15 .triangle:after{
16 position: absolute;
17 top: 12px;
18 right: 5px;
19 content: "";
20 width: 0;
21 height: 0;
22 border: 8px solid transparent;
23 border-top-color: red;
24 }
25 </style>
