http://www.olivergast.de/2012/05/31/css3-ubersicht-der-artikel-und-demos/
http://www.webresourcesdepot.com/flexible-javascript-tree-menu-dtree/

.code:after {
    -moz-transform: rotate(45deg);
    background: -moz-linear-gradient(center top , #FFA84C 0%, #FF7B0D 100%) repeat scroll 0 0 transparent;
    box-shadow: 0 1px 5px #444444;
    color: #FFFFFF;
    content: "CSS";
    font-size: 16px;
    font-weight: bold;
    height: 25px;
    line-height: 25px;
    position: absolute;
    right: -50px;
    text-align: center;
    top: 20px;
    width: 150px;
}

.code_html:after {
    -moz-transform: rotate(45deg);
    background: -moz-linear-gradient(center top , #CC0000 0%, #560000 100%) repeat scroll 0 0 transparent;
    box-shadow: 0 1px 5px #444444;
    color: #FFFFFF;
    content: "HTML";
    font-size: 16px;
    font-weight: bold;
    height: 25px;
    line-height: 25px;
    position: absolute;
    right: -50px;
    text-align: center;
    top: 20px;
    width: 150px;
}