演示图1
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>html+CSS仿百度百科导航下拉菜单</title>
<link href="css/style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div class="header">
<div class="top-bar">
头部内容
</div>
<div class="nav-bar">
<div class="nav-bg">
<div class="nav-top">
<div class="nav-content">
<ul class="nav-content-box">
<li class="index on">
<span><a href="#">首页</a></span>
</li>
<li class="cat">
<span><a href="#">分类</a></span>
<ul>
<li><a href="#">自然</a></li>
<li><a href="#">文化</a></li>
<li><a href="#">地理</a></li>
<li><a href="#">历史</a></li>
<li><a href="#">生活</a></li>
<li><a href="#">社会</a></li>
<li><a href="#">艺术</a></li>
<li><a href="#">人物</a></li>
<li><a href="#">经济</a></li>
<li><a href="#">科技</a></li>
<li><a href="#">体育</a></li>
</ul>
</li>
<li class="special ">
<span><a href="javascript:void(0)">特色百科</a></span>
<ul>
<li><a href="#">历史上的今天</a></li>
<li><a href="#">数字博物馆</a></li>
<li><a href="#">城市百科</a></li>
<li><a href="#">高校百科</a></li>
<li><a href="#">艺术百科</a></li>
<li><a href="#">科学百科</a></li>
</ul>
</li>
<li class="user">
<span><a href="javascript:void(0)">用户</a></span>
<ul>
<li><a href="#">蝌蚪团</a></li>
<li><a href="#">燃梦计划</a></li>
<li><a href="#">百科任务</a></li>
<li><a href="#">百科商城</a></li>
</ul>
</li>
<li class="cooperation">
<span><a href="javascript:void(0)">权威合作</a></span>
<ul>
<li><a href="#">合作模式</a></li>
<li><a href="#">常见问题</a></li>
<li><a href="#">联系方式</a></li>
</ul>
</li>
<li class="mobile">
<span><a href="javascript:void(0)">手机百科</a></span>
<ul>
<li><a href="#">客户端</a></li>
<li><a href="#">网页版</a></li>
</ul>
</li>
</ul>
</div>
</div>
</div>
</div>
</div>
</body>
</html>
样式
body{margin:0;padding:0;font-family:arial,tahoma,'Microsoft Yahei','\5b8b\4f53',sans-serif;;}
.top-bar{background-color:#f3f3f3;text-align:center;padding:2.5em;}
a{padding-bottom:3px;color:white;text-decoration:none;}
ul{list-style:none;padding:0;margin:0;}
li{text-align:center;}
.nav-bar{position:relative;z-index:1000;overflow:hidden;min-width:900px;height:45px;}
.nav-bar:hover{overflow:visible;-webkit-transition:all 0.5s ease;transition:all 0.5s ease;}
.nav-bg{position:absolute;width:100%;height:272px;background:#24619c;background:rgba(36,97,158,.95);-webkit-transition:.3s;transition:.3s;z-index:9999;}
.nav-top{height:43px;border-top:1px solid #5895d5;border-bottom:1px solid #3b92e9;background:#459df5;}
.nav-content{position:absolute;width:80%;left:10%;}
.nav-content-box{position:absolute;top:0;left:0;width:100%;}
.nav-content-box>li{float:left;line-height:43px;}
.nav-content-box>li:hover{background:#19508b;}
.nav-content-box>li>span>a{display:block;width:100%;margin:0;height:41px;line-height:41px;}
.nav-content-box>li:hover>span>a{background:#338ce6;}
ul>li.index,ul>li.cat,ul>li.special,ul>li.user,ul>li.cooperation,ul>li.mobile{width:120px;}
ul>li.index{height:43px;}
ul.nav-content-box>li>ul{border-right:solid 1px #3a6fa2;margin:10px 0 6px}
ul.nav-content-box>li>ul:after{visibility:hidden;display:block;font-size:0;content:" ";clear:both;height:0}
.nav-content-box>li:hover>ul{border-right:none;padding-right:1px;}
ul.nav-content-box>li>ul>li{float:left;width:100%;line-height:2;text-align:center;}
ul.nav-content-box>li.cat>ul>li{width:49%;}
ul.nav-content-box>li>ul>li>a{display:block;width:100%;}
