早上了解到一个名为"css border三角"的技术，纯css2实现,兼容各浏览器(包括Ie6)，且效果非常好，当时即"内牛满面"，顿感牛人之强大。自己不敢不有样学样，赶紧做了个应用demo,练手之余也能向更多的盆友介绍此技术。效果如下:
大家请注意：
1.外边框部分:会发现是"圆角"。
2:三角部分:哇！居然不是图片。再点击，哇，太牛x了。
纯css2实现，效果明显，技术简单，真是老少皆宜啊。demo代码如下:
<style type="text/css">
body{
padding:20px;
}
*{
padding:0;
margin:0;
}
.br-test{
width:300px;
}
.items{
border-color:#ccc;
border-style:solid;
border-width:0 2px;
padding:5px;
}
.items-item{
position:relative;
border:#CCC 1px solid;
height:18px;
margin:5px 0 0 0;
}
.items-item h3{
position:absolute;
left:24px;
font-size:14px;
}
.items-item-triangle{
position:absolute;
left:5px;
width:0;
height:0;
overflow:hidden;
font-size:0;
line-height:0;
border-color:transparent transparent transparent #CCC;
border-style:dashed dashed dashed solid;
border-width:8px;
cursor:pointer;
}
.click{
left:0;
top:5px;
border-color:#CCC transparent transparent transparent;
border-style:solid dashed dashed dashed;
}
.top-border{
border-bottom:3px solid #ccc;
border-left:3px dotted transparent;
border-right:3px dotted transparent;
}
.bottom-border{
border-top:3px solid #ccc;
border-left:3px dotted transparent;
border-right:3px dotted transparent;
}
</style>
<script type="text/javascript" src="http://www.wfuyu.com/uploads/common/js/jquery-1.4.2.min.js"></script>
</head>
<body>
<div class="br-test">
<div class="top-border"></div>
<div id="br-items" class="items">
<div class="items-item">
<div class="items-item-triangle"></div>
<h3>常用联系人</h3>
</div>
<div class="items-item">
<div class="items-item-triangle"></div>
<h3>常用联系人</h3>
</div>
<div class="items-item">
<div class="items-item-triangle"></div>
<h3>常用联系人</h3>
</div>
</div>
<div class="bottom-border"></div>
</div>
<script type="text/javascript">
$(".items-item-triangle",$("#br-items")).each(function(){
var that = $(this);
that.click(function(){
$(this).toggleClass("click");
});
});
</script>