<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<script src="js/jquery-3.4.1.min.js"></script>
<title>三级菜单</title>
<script>
</script>
<!-- 版本要求IE10 -->
<style>
.top-nav {
width: 960px;
margin: 60px auto;
/* 边框 实线 */
border: 1px solid #222;
background-color: #111;
/* 渐变 */
background-image: linear-gradient(#444, #111);
/* 圆角 */
border-radius: 6px;
/* 阴影 */
box-shadow: 0 1px 1px #777;
padding: 0;
/* 去小圆点 */
list-style: none;
}
/* 清除浮动 */
.top-nav :before,
.top-nav:after {
content: " ";
display: table;
}
.top-nav:after {
clear: both;
}
/* 强制刷新框架 */
.top-nav {
zoom: 1;
}
.top-nav li {
float: left;
border-right: 1px solid #222;
box-shadow: 0 1px 1px #444;
position: relative;
}
/* 二级菜单 */
.top-nav li a {
float: left;
padding: 12px 30px;
color: #999;
/* 字体 */
font: bold 12px;
/* 去除下划线 */
text-decoration: none;
/* 文本阴影 */
text-shadow: 0 1px 0px #000;
}
.top-nav li a:hover {
color: #fafafa;
}
.top-nav li ul {
display: none;
position: absolute;
list-style: none;
top: 38px;
/* opacity: 0; */
z-index: 1;
left: 0;
box-shadow: 0 -1 0 rgba(255, 255, 255, 0.3);
background-image: linear-gradient(#444, #111);
padding: 0px;
border-radius: 3px;
background-color: #444;
margin: 20px 0 0 0;
transition: all 0.2s ease-in-out;
}
.top-nav li:hover>ul {
display: block;
margin: 0;
}
.top-nav ul li {
left: 0;
float: none;
display: block;
border: 0;
box-shadow: 0 1px #111, 0 2px 0 #666;
margin: 0;
}
.top-nav ul a {
padding: 10px;
width: 130px;
float: none;
display: block;
}
.top-nav ul li:first-child>a {
border-radius: 3px 3px 0 0;
}
.top-nav ul li:last-child>a {
border-radius: 0 0 3px 3px;
}
.top-nav ul li:first-child > a:before{
content: " ";
position: absolute;
left: 40px;
top: -6px;
border-left: 6px solid transparent;
border-right: 6px solid transparent;
border-bottom: 6px solid #444;
}
.top-nav ul li:first-child > a :hover:before{
border-bottom-color: #04acec;
}
.top-nav ul ul {
left:150px;
top: 0;
margin: 0 0 0 20px;
box-shadow: -1px 0 0 rgba(255, 255, 255, 0.3);
}
.top-nav ul ul li:first-child > a:before{
content: " ";
left: -6px;
top:40%;
border-left: 0;
border-top: 6px solid transparent;
border-right: 6px solid #444;
border-bottom: 6px solid transparent;
}
.top-nav ul ul li:first-child a:hover:before{
border-right-color: #04acec;
border-bottom-color: transparent;
}
.top-nav ul li:first-child a:hover:before{
border-bottom-color: #04acec;
}
.top-nav ul li a:hover {
background-color: #04acec;
}
</style>
</head>
<body>
<div id="top">
<ul class="top-nav">
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</html>
