CSS3实现的横向二级下拉菜单代码实例:
横向二级下拉菜单是非常常用的效果，例如很多网站的导航栏就是这样的二级下拉菜单效果，非常好用，本章节分享一段使用CSS3实现的下拉菜单，当然当下很多浏览器都不支持，不过相信用不了多久这种现状就会被改变。
代码实例如下:
<!DOCTYPE html><html><head><meta charset="utf-8"><meta name="author" content="http://www.softwhy.com/" /><title>蚂蚁部落</title><style type="text/css">#nav{ float:left; font:bold 12px Arial, Helvetica, Sans-serif; border:1px solid #121314; border-top:1px solid #2b2e30; -webkit-border-radius:5px; -moz-border-radius:5px; border-radius:5px; overflow:hidden;}#nav ul{ margin:0; padding:0; list-style:none;}#nav ul li{float:left;}#nav ul li a{ float:left; color:#d4d4d4; padding:10px 20px; text-decoration:none; background:#3C4042; background:-webkit-gradient( linear, left bottom, left top, color-stop(0.09, rgb(59,63,65)), color-stop(0.55, rgb(72,76,77)), color-stop(0.78, rgb(75,77,77)) ); background:-moz-linear-gradient( center bottom, rgb(59,63,65) 9%, rgb(72,76,77) 55%, rgb(75,77,77) 78% ); background:-o-linear-gradient( center bottom, rgb(59,63,65) 9%, rgb(72,76,77) 55%, rgb(75,77,77) 78% ); box-shadow:0 1px 0 rgba(255, 255, 255, 0.1) inset, 0 0 5px rgba(0, 0, 0, 0.1) inset; border-left:1px solid rgba(255, 255, 255, 0.05); border-right:1px solid rgba(0, 0, 0, 0.2); text-shadow:0 -1px 1px rgba(0, 0, 0, 0.6);}#nav ul li a:hover, #nav ul li:hover > a{ color:#252525; background:#3C4042; background:-webkit-gradient( linear, left bottom, left top, color-stop(0.09, rgb(77,79,79)), color-stop(0.55, rgb(67,70,71)), color-stop(0.78, rgb(69,70,71)) ); background:-moz-linear-gradient( center bottom, rgb(77,79,79) 9%, rgb(67,70,71) 55%, rgb(69,70,71) 78% ); background:-o-linear-gradient( center bottom, rgb(77,79,79) 9%, rgb(67,70,71) 55%, rgb(69,70,71) 78% ); text-shadow:0 1px 0 rgba(255, 255, 255, 0.2), 0 -1px #000;}#nav li ul a:hover, #nav ul li li:hover > a{ color:#2c2c2c; background:#5C9ACD; background:-webkit-gradient( linear, left bottom, left top, color-stop(0.17, rgb(61,111,177)), color-stop(0.51, rgb(80,136,199)), color-stop(1, rgb(92,154,205)) ); background:-moz-linear-gradient( center bottom, rgb(61,111,177) 17%, rgb(80,136,199) 51%, rgb(92,154,205) 100% ); background:-o-linear-gradient( center bottom, rgb(61,111,177) 17%, rgb(80,136,199) 51%, rgb(92,154,205) 100% ); border-bottom:1px solid rgba(0, 0, 0, 0.6); border-top:1px solid #7BAED9; text-shadow:0 1px rgba(255, 255, 255, 0.3);}#nav li ul { background:#3C4042; background-image:-webkit-gradient( linear, left bottom, left top, color-stop(0.09, rgb(77,79,79)), color-stop(0.55, rgb(67,70,71)), color-stop(0.78, rgb(69,70,71)) ); background-image:-moz-linear-gradient( center bottom, rgb(77,79,79) 9%, rgb(67,70,71) 55%, rgb(69,70,71) 78% ); background-image:-o-linear-gradient( center bottom, rgb(77,79,79) 9%, rgb(67,70,71) 55%, rgb(69,70,71) 78% ); border-radius:0 0 10px 10px; -moz-border-radius:0 0 10px 10px; -webkit-border-radius:0 0 10px 10px; left:-999em; margin:35px 0 0; position:absolute; width:160px; z-index:9999; box-shadow:0 0 15px rgba(0, 0, 0, 0.4) inset; -moz-box-shadow:0 0 15px rgba(0, 0, 0, 0.4) inset; -webkit-box-shadow:0 0 15px rgba(0, 0, 0, 0.4) inset; border:1px solid rgba(0, 0, 0, 0.5);}#nav li:hover ul{left: auto;}#nav li ul a{ background: none; border: 0 none; margin-right: 0; width: 120px; box-shadow: none; -moz-box-shadow: none; -webkit-box-shadow: none; border-bottom: 1px solid transparent; border-top: 1px solid transparent;}#nav li li ul{ margin: -1px 0 0 160px; -webkit-border-radius: 0 10px 10px 10px; -moz-border-radius: 0 10px 10px 10px; border-radius: 0 10px 10px 10px; visibility:hidden;}#nav li li:hover ul{visibility:visible;}#nav ul ul li:last-child > a{ -moz-border-radius:0 0 10px 10px; -webkit-border-radius:0 0 10px 10px; border-radius:0 0 10px 10px;}#nav ul ul ul li:first-child > a{ -moz-border-radius:0 10px 0 0; -webkit-border-radius:0 10px 0 0; border-radius:0 10px 0 0;}</style></head><body><div style="margin: 0pt auto; width: 740px;"> <div id="nav"> <ul> <li><a href="#">网站首页</a></li> <li><a href="#">关于我们</a></li> <li><a href="#">CSS3作品</a></li> <li><a href="#">下拉菜单</a> <ul> <li><a href="#">ASP</a></li> <li><a href="#">PHP</a></li> <li><a href="#">JSP</a></li> </ul> </li> <li><a href="#">三级下拉</a> <ul> <li><a href="#">AJAX</a></li> <li><a href="#">EXTJS</a></li> <li><a href="#">脚本资源</a> <ul> <li><a href="#">Javascript</a></li> <li><a href="#">jquery</a></li> <li><a href="#">prototype</a></li> <li><a href="#">Mooltoos</a></li> </ul> </li> <li><a href="#">HTML5</a></li> <li><a href="#">Chrome</a></li> </ul> </li> <li><a href="#">服务</a></li> <li><a href="#">联系我们</a></li> </ul> </div></div><br><br></body></html>原文地址是:http://www.softwhy.com/forum.php?mod=viewthread&tid=10900
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