.thumb{
  -webkit-box-shadow: 5px 5px 5px 0px #777;  /* Safari 3-4, iOS 4.0.2 - 4.2, Android 2.3+ */
  -moz-box-shadow:    5px 5px 5px 0px #777;  /* Firefox 3.5 - 3.6 */
  box-shadow:         5px 5px 5px 0px #777;  /* Opera 10.5, IE 9, Firefox 4+, Chrome 6+, iOS 5 */
}

.thumb:{opacity: 1;}
.thumb:hover{opacity: 0.7;}

.thumb:active{
    -moz-box-shadow: none;
    -webkit-box-shadow: none;
    box-shadow: none;
}