<style type="text/CSS">
div#mid{margin:0px 20px;background:#FFBA00;font-size:14px;}
p {padding:5px 10px;margin:2px;text-align:center;}
div.rtop {display:block;background:#fff}
div.rtop div{display:block;height:1px;overflow:hidden;background:#FFBA00}
div.r1{margin:0px 3px}
div.r2{margin:0px 2px}
div.r3{margin:0px 1px}
div.rtop div.r4 {margin:0 1px;height:1px}
</style>
<div id="mid">
<div class="rtop">
<div class="r1"></div>
<div class="r2"></div>
<div class="r3"></div>
<div class="r4"></div>
</div>
<p>div + CSS 圆角矩形</p>
<div class="rtop">
<div class="r4"></div>
<div class="r3"></div>
<div class="r2"></div>
<div class="r1"></div>
</div>
</div>