<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>三角形</title>
<style>
body {}
#sjx {
width:0;
height:0;
_width:8px;
_height:6px;
_display:block;
border-width:6px 5px 0;
_border-width:0px;
border-style:solid;
border-color:#fC0 transparent transparent;
_border-color:none;
_background:url(../images/iconSJXc3.gif) no-repeat;//IE6牛B些，需要做个三角形的图片
</style>
</head>
<body>
<div id="sjx"></div>
</body>
</html>原文：http://blog.csdn.net/xbruin/article/details/22037483