帮我看看我这个三级栏为什么不出现？
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
*{
margin: 0;
padding: 0;
}
.page{
width: 100%;
height: 4043px;
background: url("https://timgsa.baidu.com/timg?image&quality=80&size=b9999_10000&sec=1550675751768&di=9c864fe99df038b9d377d382ab1dddd6&imgtype=0&src=http%3A%2F%2Fgss0.baidu.com%2F7Po3dSag_xI4khGko9WTAnF6hhy%2Fzhidao%2Fwh%3D450%2C600%2Fsign%3De01bcbb01430e924cff1943579384230%2F7c1ed21b0ef41bd54a7d3e4c5ada81cb39db3d58.jpg") center top no-repeat;
}
.nav{
width: 160px;
height: 205px;
position: fixed;
left: 0;
top: 50%;
margin-top: -103px;
font-family: 'Miscrosoft YaHei';
}
.tit{
width: 160px;
height: 40px;
}
.nav-li{
width: 160px;
height: auto;
border-bottom: 1px solid #FFF;
background: #333;
text-align: center;
line-height: 40px;
color: #FFF;
font-size: 16px;
cursor: pointer;
}
.nav-li:hover ul{ /*隐藏二级*/
display: block;
}
.nav-li ul{
width: 160px;
height: auto;
background: #FFF;
display: none; /*隐藏二级*/
}
.nav-li ul li{
width: 160px;
height: 40px;
border-bottom: 1px dashed #666;
color: #333;
text-align: center;
line-height: 40px; /*行高*/
position: relative;
}
.nav-li ul li:haver .list-3{
display: block;
}
.list-3{
width: 160px;
height: auto;
position: absolute; /*定位属性，三级在旁边展开*/
left: 160px;
top: 0px;
display: none;
}
.list-3Dom{
width: 160px;
height: 40px;
background: #444;
border-bottom: 1px solid #FFF;
text-align: center;
line-height: 40px;
color: #FFF;
}
</style>
</head>
<body>
<div class="page">
<div class="nav">
<div class="nav-li">
<div class="tit">标题</div>
<ul>
<li>
二级栏目
<div class="list-3">
<div class="list-3Dom">三级</div>
<div class="list-3Dom">三级</div>
<div class="list-3Dom">三级</div>
</div>
</li>
<li>
二级栏目
</li>
<li>
二级栏目
</li>
</ul>
</div>
<div class="nav-li">标题标题</div>
<div class="nav-li">标题标题</div>
<div class="nav-li">标题标题</div>
</div>
</div>
</body>
</html>
