.thumb
{
  margin-bottom: 4px;
  margin-right: 4px;
}

.thumb img
{
  border: 1px solid #ddd;
  width: 75px;
  height: 75px;
}

.thumb a:focus img,
.thumb a:hover img,
.thumb a:active img
{
 border: 1px solid #46718F;
}