facebook box-shadow css
background: -moz-linear-gradient(top, rgba(43,43,43,0) 0%, rgba(43,43,43,0) 40%, rgba(43,43,43,1) 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,rgba(43,43,43,0)), color-stop(40%,rgba(43,43,43,0)), color-stop(100%,rgba(43,43,43,1))); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, rgba(43,43,43,0) 0%,rgba(43,43,43,0) 40%,rgba(43,43,43,1) 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, rgba(43,43,43,0) 0%,rgba(43,43,43,0) 40%,rgba(43,43,43,1) 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, rgba(43,43,43,0) 0%,rgba(43,43,43,0) 40%,rgba(43,43,43,1) 100%); /* IE10+ */
background: linear-gradient(to bottom, rgba(43,43,43,0) 0%,rgba(43,43,43,0) 40%,rgba(43,43,43,1) 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#002b2b2b', endColorstr='#2b2b2b',GradientType=0 ); /* IE6-9 */