1.文本框鼠标/焦点处理
<input type="text" name="userid" value="USERNAME" onfocus="this.value = ‘‘;" onblur="if (this.value == ‘‘) {this.value = ‘USERNAME‘;}">
2.三角形图表fontawesone/纯css
链接http://fontawesome.dashgame.com/
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<link href="font-awesome-4.7.0/css/font-awesome.min.css" rel="stylesheet">
<title></title>
<style type="text/css">
.demo{
position: relative;
}
.demo:after {
border: 10px solid transparent;
border-left: 10px solid #f00;
width: 0;
height: 0;
position: absolute;
content: ‘ ‘
}
</style>
.demo{
position: relative;
}
.demo:after {
border: 10px solid transparent;
border-left: 10px solid #f00;
width: 0;
height: 0;
position: absolute;
content: ‘ ‘
}
</head>
<body>
<span class="demo">文字内容</span>
::after
<ul>
<i class="fa fa-caret-right"></i>
</ul>
</body>
原文：http://www.cnblogs.com/ayyayy/p/6096777.html