.lightbox-thumbnail {
  padding: 15px;
}

.col-md-3 .lightbox-thumbnail {
  max-width: 240px;
  height: auto;
  min-height: 240px;
  max-height: 240px;
}

.col-md-4 .lightbox-thumbnail {
  margin-left: auto;
  margin-right: auto;
  display: block;
}

.col-md-6 .lightbox-thumbnail {
  margin-left: auto;
  margin-right: auto;
  display: block;
}

.col-md-12 .lightbox-thumbnail {
  margin-left: auto;
  margin-right: auto;
  display: block;
}