.top
{
	width:220px;
  height:150px;
  border-radius:10px;
  box-shadow: 4px 4px 6px #888888;
  border:1px solid orange;
}
.bottom
{
  width:220px;
  height:150px; 
  border-radius:10px;
  box-shadow: 4px 4px 6px #888888;
  border:1px solid orange;
}

#cf {
 position:relative;
  
}

#cf img {
  position:absolute;
  left:0;
  -webkit-transition: opacity 1s ease-in-out;
  -moz-transition: opacity 1s ease-in-out;
  -o-transition: opacity 1s ease-in-out;
  transition: opacity 1s ease-in-out;
}

#cf img.top:hover 
{
  opacity:0;
}