body{ background: url("/images/bg.jpg") top center; }
div.body{ width: 748px; height: 589px; background: url("/images/overlay-trans.png") top center; margin: 0px auto 0px auto; position: relative; }
div.link{ width: 748px; height: 47px;  position: relative; margin: 10px auto; }
a{ display:block; width: 262px; height: 47px; background: url("/images/button.jpg"); outline: none; text-indent: -9999px; position: absolute; top: 0px; left: 269px;} 
a:hover{background-position: 0px -47px; }