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a:visited{color:white;text-decorative:none;}
a:hover{color:white;text-decorative:none;}
a:active{color:white;text-decorative:none;}
li{float:left;display:inline;background-color:#003366;width:120px;text-align:center;margin:2px;padding:10px 0 5px 0;position:relative;}
.limouseover{background-color:#0033ff;color:red;}
.limouseout{background-color:#003366;color:black;}
li ul{display:none;width:120px;position:absolute;left:0;top:30px;}
li ul li{margin:0px auto;border-top:1px solid #006699;}

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<ul id=menu1>
<li><a href="">首頁</a></li>
<li><a href="">菜單1菜單1</a>
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<li><a href="">子菜單1子菜單1子菜單1子菜單1</a></li>
<li><a href="">子菜單2</a></li>
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