<link rel="stylesheet" type="text/css" href="bootstrap-3.3.0-dist/dist/css/bootstrap.min.css" rel="external nofollow" >
<script src="bootstrap-3.3.0-dist/dist/js/jquery-1.11.2.min.js"></script>
<script src="bootstrap-3.3.0-dist/dist/js/bootstrap.min.js"></script>

<div class="tree well">
 <ul>
 <li> <span><i class="icon-folder-open"></i> 廊坊师范学院</span>
  <ul>
  <li> <span><i class="icon-minus-sign"></i> 教育学院</span>
   <ul>
   <li> <span><i class="icon-leaf"></i> 学前教育</span> </li>
   </ul>
  </li>
  <li> <span><i class="icon-minus-sign"></i> 物电学院</span>
   <ul>
   <li> <span><i class="icon-leaf"></i> 电气工程技术</span> </li>
   <li> <span><i class="icon-minus-sign"></i> 电子信息科学技术</span>
    <ul>
    <li> <span><i class="icon-minus-sign"></i> 电子一班</span>
     <ul>
     <li> <span><i class="icon-leaf"></i> 宋笑</span> </li>
     <li> <span><i class="icon-leaf"></i> 二盟</span> </li>
     </ul>
    </li>
    <li> <span><i class="icon-leaf"></i> 电子二班</span> </li>
    </ul>
   </li>
   <li> <span><i class="icon-leaf"></i> 物理学</span> </li>
   </ul>
  </li>
  </ul>
 </li>
 </ul>
</div>

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 -moz-box-shadow:inset 0 1px 1px rgba(0, 0, 0, 0.05);
 box-shadow:inset 0 1px 1px rgba(0, 0, 0, 0.05)
}
.tree li {
 list-style-type:none;
 margin:0;
 padding:10px 5px 0 5px;
 position:relative
}
.tree li::before, .tree li::after {
 content:'';
 left:-20px;
 position:absolute;
 right:auto
}
.tree li::before {
 border-left:1px solid #999;
 bottom:50px;
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}
.tree li::after {
 border-top:1px solid #999;
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 border:1px solid #999;
 border-radius:5px;
 display:inline-block;
 padding:3px 8px;
 text-decoration:none
}
.tree li.parent_li>span {
 cursor:pointer
}
.tree>ul>li::before, .tree>ul>li::after {
 border:0
}
.tree li:last-child::before {
 height:30px
}
.tree li.parent_li>span:hover, .tree li.parent_li>span:hover+ul li span {
 background:#eee;
 border:1px solid #94a0b4;
 color:#000
}

<script type="text/javascript">
 //为节点添加展开，关闭的操作
$(function(){
 $('.tree li:has(ul)').addClass('parent_li').find(' > span').attr('title', 'Collapse this branch');
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