.gallerycontainer{ 
 position: relative;
 height: 60px; 
 }

.thumbnail img{
border: 1px solid white;
margin: 1px;
}

.thumbnail:hover{
background-color: transparent;
}

.thumbnail:hover img{
border: 1px solid black;
}

.thumbnail:hover img.big{
border-width: 30px 30px 30px 30px;
border-style: solid;
border-color: black;
}

/*CSS for enlarged image*/
.thumbnail span {
position: absolute;
background-color: transparent;
visibility: hidden;
color: yellow;
}
.thumbnail em {
position: absolute;
background-color: transparent;
visibility: hidden;
color: yellow;
}

.thumbnail:hover span{ /*CSS for enlarged image*/
visibility: visible;
top: -5px;
left: 250px; /*position where enlarged image should offset horizontally */
z-index: 50;
}
.thumbnail:hover em{ /*CSS for enlarged image*/
visibility: visible;
top: 2px;
left: 300px; /*position where enlarged image should offset horizontally */
z-index: 60;
}