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

}

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

.thumbnail span{ 
font-family: Verdana, Arial, Helvetica, sans-serif;
font-size:9px;
position: absolute;
background-color: #FFFFFF;
padding: 5px;
left: -1000px;
border: 1px dashed #000000;
visibility: hidden;
color: black;
text-decoration: none;
}

.thumbnail span img{ 
border-width: 0;
padding: 2px;
}

.thumbnail:hover span{ 
visibility: visible;
top: 40px;
left: 40px;

}