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

.thumbnail:hover{
background-color: transparent;
z-index: 1;
}

.thumbnail span{ 
position: absolute;
background-color: #f3f3f3;
padding: 1px;
left: -1000px;
border: 1px gray;
visibility: hidden;
color: #192669;
text-decoration: none;
}

.thumbnail span img{ 
border-width: 0;
padding: 1px;
}

.thumbnail:hover span{ 
visibility: visible;
left: -58px; 
top: -90px;
z-index: 2;
}