.thumbnail{
position: relative;
z-index: 0;
}

.thumbnail:hover{
background-color: #FFFFFF;
z-index: 50;
}

.thumbnail span{ /*CSS for enlarged image*/
position: absolute;
background-color: #FFFFFF;
padding: 5px;

visibility: hidden;
color: black;
text-decoration: none;
}

.thumbnail span img{ /*CSS for enlarged image*/
border-width: 0;
padding: 2px;
}

.thumbnail:hover span{ /*CSS for enlarged image on hover*/
visibility: visible;
/*position where enlarged image should offset horizontally