div.AJAX_contents {
  text-align:center;
  width:100%
}
div.AJAX_background {
  position:relative;
  top:0px;
  bottom:0px;
  left:0px;
  right:0px;
  overflow:hidden;
  padding:0;
  margin:0;
  filter:alpha(opacity=50);
  opacity:0.5;
}