<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf-8">
<title>导航</title>
<style type="text/css">
*{margin: 0;padding: 0;}
.menu,.menu ul,.menu li,.menu a{margin: 0;padding: 0;border: none;outline: none;}
.menu{height: 40px;width: 510px;background: #4c4e5a;background: -webkit-linear-gradient(top, #4c4e5a 0%,#2c2d33 100%);background: -moz-linear-gradient(top, #4c4e5a 0%,#2c2d33 100%);background: -o-linear-gradient(top, #4c4e5a 0%,#2c2d33 100%);background: -ms-linear-gradient(top, #4c4e5a 0%,#2c2d33 100%);background: linear-gradient(top, #4c4e5a 0%,#2c2d33 100%);-webkit-border-radius: 5px;-moz-border-radius: 5px;border-radius: 5px;}
.menu li{position: relative;list-style: none;float: left;display: block;height: 40px;}
.menu li a{display: block;padding: 0 14px;margin: 6px 0;line-height: 28px;text-decoration: none;border-left: 1px solid #393942;border-right: 1px solid #4f5058;font-family: Helvetica, Arial, sans-serif;font-weight: bold;font-size: 13px;color: #f3f3f3;text-shadow: 1px 1px 1px rgba(0,0,0,.6);-webkit-transition: color .2s ease-in-out;-moz-transition: color .2s ease-in-out;-o-transition: color .2s ease-in-out;-ms-transition: color .2s ease-in-out;transition: color .2s ease-in-out;}
.menu li:first-child a{border-left: none;}
.menu li:last-child a{border-right: none;}
.menu li:hover > a{color: #8fde62;}
.menu ul{position: absolute;top: 40px;left: 0;opacity: 0;background: #1f2024;-webkit-border-radius: 0 0 5px 5px;-moz-border-radius: 0 0 5px 5px;border-radius: 0 0 5px 5px;-webkit-transition: opacity .25s ease .1s;-moz-transition: opacity .25s ease .1s;-o-transition: opacity .25s ease .1s;-ms-transition: opacity .25s ease .1s;transition: opacity .25s ease .1s;}
.menu li:hover > ul{opacity: 1;}
.menu ul li{height: 0;overflow: hidden;padding: 0;-webkit-transition: height .25s ease .1s;-moz-transition: height .25s ease .1s;-o-transition: height .25s ease .1s;-ms-transition: height .25s ease .1s;transition: height .25s ease .1s;}
.menu li:hover > ul li{height: 36px;overflow: visible;padding: 0;}
.menu ul li a{width: 100px;padding: 4px 0 4px 40px;margin: 0;border: none;border-bottom: 1px solid #353539;}
.menu ul li:last-child a{border: none;}
.menu a.documents{background: url(../img/docs.png) no-repeat 6px center;}
.menu a.messages{background: url(../img/bubble.png) no-repeat 6px center;}
.menu a.signout{background: url(../img/arrow.png) no-repeat 6px center;}
</style>
</head>
<body>
<ul class="menu">
<li><a href="
http://www.web0752.com/">网站建设</a></li>
<li><a href="
http://www.web0752.com/">网站制作</a></li>
<li><a href="
http://www.web0752.com/">网站优化</a>
<ul>
<li><a href="#" class="documents">Documents</a></li>
<li><a href="#" class="messages">Messages</a></li>
<li><a href="#" class="signout">Sign Out</a></li>
</ul>
</li>
<li><a href="#">Uploads</a></li>
<li><a href="#">Videos</a></li>
<li><a href="#">Documents</a></li>
</ul>
</body>
</html>
他的教程,多了一个</li>
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