abstract：<!DOCTYPE html><html> <head> <meta charset="UTF-8"> <title></title> <script type="text/javascript" src="js/jquery-3.3.1.min.js"&
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script type="text/javascript" src="js/jquery-3.3.1.min.js"></script>
<style type="text/css">
*{margin: 0px;padding: 0px;}
.menu { width: 800px;height: 35px;margin: 0px auto;background: #000; margin-top: 20px;color: #fff; border:1px solid #ccc;border-radius: 5px; }
ul{list-style: none;}
ul li{width: 100px;height: 35px;line-height: 35px;text-align: center;float: left;border-right: 1px solid #ccc;cursor: pointer;}
.twomenu li{width: 100px;height: 30px;line-height: 30px;background: #2D2D2D;color: #A9A9A9; font-size: 14px;position: relative;border:0px;}
.twomenu li:hover{background: #000000; color: #fff;}
.three{position: absolute;top: 0px;left: 100px;}
.three li{width: 99px; height: 30px;line-height: 30px;border: 0;}
</style>
<script type="text/javascript">
$(document).ready(function(){
$('.twomenu').hide();
$('.three').hide();
$('.one>li').mouseover(function(){
$(this).find('.twomenu').slideDown(500)
})
$('.one>li').mouseleave(function(){
$(this).find('.twomenu').slideUp(500)
})
$('.two').mouseover(function(){
$(this).find('.three').slideDown(500)
})
$('.two').mouseleave(function(){
$(this).find('.three').slideUp(500)
})
})
</script>
</head>
<body>
<div class="menu">
<ul class="one">
<li>首页</li>
<li>产品
<ul class="twomenu">
<li>产品1</li>
<li class="two">产品2
<ul class="three">
<li>产品2.1</li>
<li>产品2.2</li>
<li>产品2.3</li>
</ul>
</li>
</ul>
</li>
</ul>
</div>
</body>
</html>
Correcting teacher：查无此人Correction time：2019-05-22 09:20:01
Teacher's summary：完成的不错。三级菜单这个效果，项目中基本都会用到。继续加油