.gallerycontainer{
position: relative;
/*Add a height attribute and set to largest image's height to prevent overlaying*/
}

.thumbnail img{
border: 1px solid black;
margin: 0 5px 5px 0;
}

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

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

.thumbnail span{ /*CSS for enlarged image*/
position: absolute;
padding: 5px;
left: -100px;
border: 1px dashed black;
visibility: hidden;
color: black;
text-decoration: none;
width: 300px;
}

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

.thumbnail:hover span{ /*CSS for enlarged image*/
visibility: visible;
top: -285px;
left: 230px; /*position where enlarged image should offset horizontally */
z-index: 50;
}


.smallgallery{
position: relative; padding: 5px;
/*Add a height attribute and set to largest image's height to prevent overlaying*/
}

.smallthumb img{
border: 1px solid black; 
margin: 0 5px 5px 0;
}

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

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

.smallthumb span{ /*CSS for enlarged image*/
position: absolute;
padding: 5px;
left: -100px;
border: 1px dashed black;
visibility: hidden;
color: black;
text-decoration: none;
width: 300px;
}

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

.smallthumb:hover span{ /*CSS for enlarged image*/
visibility: visible;
top: -145px;
left: 200px; /*position where enlarged image should offset horizontally */
z-index: 49;
}