<script type="text/javascript">function ShowSub(li) {//函數(shù)定義var subMenu = li.getElementsByTagName("ul")[0] ;//獲取subMenu.style.display = " block ";}function HideSub(li) {var subMenu = li.getElementsByTagName("ul")[0];subMenu.style.display = " none ";}</script>

*{ margin:0px; padding:0px;}body{ font-family:Verdana, Geneva, sans-serif; font-size:14px;}#nav{ width:600px; height:40px; background-color:#eee; margin:0 auto;}ul{ list-style:none;}ul li{ float:left; line-height:40px; text-align:center; width:100px;}//ie7顯示寬度的兼容性 設(shè)置width 而不用padding的自適應(yīng)a{ text-decoration:none; color:#000; display:block;}a:hover{ color:#F00; background-color:#666;}ul li ul li{ float:none;background-color:#eee; margin:2px 0px;}ul li ul{ display:none;}

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