用div+css实现三角形，三角形内有字
如下图：
------解决方案--------------------
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
.a{
border-bottom:1px solid #aaa;
height:50px;
width:100px;
position:relative;
overflow:hidden;
}
.b{
position:absolute;
display:block;
top:0px;
left:0px;
width:100px;
height:50px;
}
.b i,.b em{
position:absolute;
left:0px;
bottom:0px;
border-color:transparent;
border-color:rgba(255,255,255,0);
border-style:solid;
border-width:0 50px 50px 50px;
}
.b i{
border-bottom-color:#aaa;
}
.b em{
border-bottom-color:#FFF;
bottom:-1px;
}
.text{
position:absolute;
bottom:10px;
background:none;
border:none;
outline:none;
text-align:center;
width:100%;
}
</style>
</head>
<body>
<div class = "a">
<span class = "b">
<i></i>
<em></em>
</span>
<input type = "text" value = "文字" class = "text"/>
</div>
</body>
</html>
用定位模拟呢的，试试看哦。