沒事做了一個淘寶導航的小三角箭頭圖標，測試/支持環境：IE7+、Firefox8、chrome
以下為源碼：
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<title>css實現的交互小三角箭頭圖標 -poluoluo.com網頁教學網</title>
<style type="text/css">
* {padding:0; margin:0;font:16px/22px verdana,"microsoft yahei";}
div {width:400px; height:22px; background:#eee;margin:20px auto; padding:0 20px;}
b {width:0; height:0;+margin-top:-15px;display:inline-block;border-color:#000 #eee #eee; border-style:solid; border-width:10px 10px 0;}
strong {font-weight:500;margin:0 5px 0 0;}
a {color:#333; text-decoration:none;}
a:hover {color:#666}
a:hover b {border-color:#eee #eee #000;border-width:0 10px 10px;}
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<a href="#"><strong>菜單</strong><b></b></a>
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