.four_for_four{
	background:#000;
	position:absolute;
	display:block;
	width:325px;
	height:290px;
	top:7px;
	  /* for IE */
  filter:alpha(opacity=25);
  /* CSS3 standard */
  opacity:0.25;
}
.four_for_four:hover{
	  /* for IE */
  filter:alpha(opacity=0);
  /* CSS3 standard */
  opacity:0.0;
}

#tl{
	left:0;
}
#tr{
	right:5px;
}
#bl{
	top:296px;
	left:0;
}
#br{
	top:296px;
	right:5px;
}