If someone wants vertical version of the treeview from Harsh's answer, you can save some time:
http://jsfiddle.net/Fh47n/
.tree li {
margin: 0px 0;
list-style-type: none;
position: relative;
padding: 20px 5px 0px 5px;
}
.tree li::before{
content: '';
position: absolute;
top: 0;
width: 1px;
height: 100%;
right: auto;
left: -20px;
border-left: 1px solid #ccc;
bottom: 50px;
}
.tree li::after{
content: '';
position: absolute;
top: 30px;
width: 25px;
height: 20px;
right: auto;
left: -20px;
border-top: 1px solid #ccc;
}
.tree li a{
display: inline-block;
border: 1px solid #ccc;
padding: 5px 10px;
text-decoration: none;
color: #666;
font-family: arial, verdana, tahoma;
font-size: 11px;
border-radius: 5px;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
}
/*Remove connectors before root*/
.tree > ul > li::before, .tree > ul > li::after{
border: 0;
}
/*Remove connectors after last child*/
.tree li:last-child::before{
height: 30px;
}
/*Time for some hover effects*/
/*We will apply the hover effect the the lineage of the element also*/
.tree li a:hover, .tree li a:hover+ul li a {
background: #c8e4f8; color: #000; border: 1px solid #94a0b4;
}
/*Connector styles on hover*/
.tree li a:hover+ul li::after,
.tree li a:hover+ul li::before,
.tree li a:hover+ul::before,
.tree li a:hover+ul ul::before{
border-color: #94a0b4;
}