"

From 2013.igem.org

body {

 font-family: 'Lucida Grande', 'Helvetica Neue', Helvetica, Arial, sans-serif;
 padding: 20px 50px 150px;
 font-size: 13px;
 text-align: center;
 background: #555;

}

ul {

 text-align: left;
 display: inline;
 margin: 0;
 padding: 15px 4px 17px 0;
 list-style: none;
 -webkit-box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);
 -moz-box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);
 box-shadow: 0 0 5px rgba(0, 0, 0, 0.15);

}

ul li {

 font: bold 12px/18px sans-serif;
 display: inline-block;
 margin-right: -4px;
 position: relative;
 padding: 15px 20px;
 background: #fff;
 cursor: pointer;
 -webkit-transition: all 0.2s;
 -moz-transition: all 0.2s;
 -ms-transition: all 0.2s;
 -o-transition: all 0.2s;
 transition: all 0.2s;

} ul li:hover {

 background: #555;
 color: #fff;

} ul li ul {

 padding: 0;
 position: absolute;
 top: 48px;
 left: 0;
 width: 150px;
 -webkit-box-shadow: none;
 -moz-box-shadow: none;
 box-shadow: none;
 display: none;
 opacity: 0;
 visibility: hidden;
 -webkit-transiton: opacity 0.2s;
 -moz-transition: opacity 0.2s;
 -ms-transition: opacity 0.2s;
 -o-transition: opacity 0.2s;
 -transition: opacity 0.2s;

} ul li ul li {

 background: #555; 
 display: block; 
 color: #fff;
 text-shadow: 0 -1px 0 #000;

} ul li ul li:hover { background: #666; } ul li:hover ul {

 display: block;
 opacity: 1;
 visibility: visible;

}