.lightbox-overlay {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.9);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 9999;
}
.lightbox-overlay img {
  max-width: 90%;
  max-height: 90%;
  border: 4px solid white;
  border-radius: 8px;
}