.thumbnail{
position: relative;
z-index: 400;
}

.thumbnail:hover{
background-color: transparent;
z-index: 500;
}

.thumbnail b{
position: absolute;
background-color: lightyellow;
padding: 5px 5px 5px 0px;
left: -1000px;
border: 1px solid #88ccff;
visibility: hidden;
}

.thumbnail:hover b{
visibility: visible;
top: 0px;
left: 160px;
}