出不来效果
<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
<style>
*{
padding: 0;
margin: 0;
}
.page{
width: 100%;
height: 4000px;
background:url("mooc.jpg") conter top no-repeat;
}
.nav{
width: 160px;
height: 205px;
position: fixed;
left: 0;
top: 50%;
margin-top: -103px;
font-family: "微软雅黑";
}
.nav-li{
width:160px;
height: auto;
border-bottom: 1px solid #fff;
background-color: #333;
text-align: center;
line-height: 40px;
color: #fff;
font-size: 16px;
cursor:pointer;
}
.tit{
width: 160px;
height: 40px;
}
.mav-li:hover ul{
display: block;
}
.mav-li ul{
width: 160px;
height: auto;
background: #fff;
display: none;
}
.nav-li ul li{
width: 160px;
height: 40px;
border-bottom: 1px dashed #666;
color: #333;
text-align: center;
line-height: 40px;
}
</style>
</head>
<body>
<div class="page">
<div class="nav">
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
<div class="nav-li">
<div class="tit">慕课网的标题</div>
<ul>
<li>二级栏目</li>
<li>二级栏目</li>
<li>二级栏目</li>
</ul>
</div>
</div>
</div>
</body>
</html>
