.nav {
	font-family: Tahoma;
	font-size: 12px;
	font-style: normal;
	line-height: normal;
	font-weight: bold;
	font-variant: normal;
	text-transform: none;
	color: #056CC9;
	text-decoration: none;

}
a {
  color: #056CC9;
  text-decoration: none;
}

a:visited {
  color: #056CC9;
}

a:hover {
  colour: #aba7a7 
 }
<style type="text/css">

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

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

.thumbnail span{ /*CSS for enlarged image*/
position: absolute;
background-color: lightyellow;
padding: 5px;
right: -1000px;
border: 1px dashed gray;
visibility: hidden;
color: black;
text-decoration: none;
}

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

.thumbnail:hover span{ /*CSS for enlarged image on hover*/
visibility: visible;
top: 0;
right: 20px; /*position where enlarged image should offset horizontally */

}

</style>