#wb_tree span{
   border: 1px solid gray;
   cursor: pointer;
   display: inline-block;
   height: 10px;
   width: 10px;
   font-size: 13px;
   line-height: 11px;
   text-align: center;
   vertical-align: middle;
   margin-right: 5px;
   border-radius: 2px;
}
#wb_tree ul{
	list-style: none;
}
#wb_tree ul li{
   margin-left: 10px;
}
#wb_tree ul ul{
   margin-left: 7px;
   border-left: 1px dashed gray;
}
#wb_tree ul ul li{
   padding-left: 10px;
   position: relative
}
#wb_tree ul ul li:before{
   content: "";
   position: absolute;
   border-bottom: 1px dashed gray;
   left: -10px;
   top: 15px;
   width: 15px;
   height: 1px;
}