CSS3 Treeview Without any JavaScript | Nested, Expandable Folders

This is the css, html code for displaying Treeview Without any JavaScript
Demo: Course folder at http://www.liketly.com/course/features/ 
.css-treeview ul,
.css-treeview li
{
padding: 0;
margin: 0;
list-style: none;
}

.css-treeview input
{
position: absolute;
opacity: 0;
}

.css-treeview
{
font: normal 11px "Segoe UI", Arial, Sans-serif;
-moz-user-select: none;
-webkit-user-select: none;