<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<style type="text/css">
*{
padding: 0;
margin: 0;
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ul,li{
list-style: none;
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#warp{
width: 600px;
height: auto;
margin: 0 auto;
margin-top: 20px;
}
#warp .content p{
width: 300px;
height: 30px;
background-color: #000;
color: #fff;
line-height: 30px;
text-align: center;
}
#warp .content+ .content{
margin-top: 2px;
}
#warp .content ul{
display: none;
}
#warp .content ul.on{
display: block;
}
#warp .content li{
background-color: #ccc;
width: 300px;
text-align: center;
}
#warp .content li + li{
margin-top: 1px;
}
</style>
<body>
<div id="warp">
<div class="content">
<p>动物</p>
<ul>
<li>猴子</li>
<li>大象</li>
<li>狮子</li>
</ul>
</div>
<div class="content">
<p>山川</p>
<ul>
<li>长江</li>
<li>黄河</li>
<li>井水</li>
</ul>
</div>
<div class="content">
<p>美女</p>
<ul>
<li>貂蝉</li>
<li>西施</li>
<li>秀秀</li>
</ul>
</div>
</div>
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aUl = document.getElementsByTagName("ul"),
index;
console.log(oP.length);
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oP[i].onclick = function(){
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