.gp-lightbox {
  position: fixed; inset: 0; z-index: 9999;
  background: rgba(15, 15, 15, .94);
  display: none;
  align-items: center; justify-content: center;
  -webkit-tap-highlight-color: transparent;
  animation: gp-lb-fade .2s ease;
}
.gp-lightbox.is-open { display: flex; }
@keyframes gp-lb-fade { from { opacity: 0; } to { opacity: 1; } }

.gp-lightbox-stage {
  max-width: 92vw; max-height: 90vh;
  display: flex; align-items: center; justify-content: center;
  position: relative;
}
.gp-lightbox-img {
  max-width: 92vw; max-height: 90vh;
  width: auto; height: auto;
  object-fit: contain;
  box-shadow: 0 20px 60px rgba(0, 0, 0, .5);
  border-radius: 6px;
  user-select: none; -webkit-user-drag: none;
  animation: gp-lb-zoom .25s ease;
}
@keyframes gp-lb-zoom { from { transform: scale(.95); opacity: 0; } to { transform: scale(1); opacity: 1; } }

.gp-lightbox-btn {
  position: absolute;
  background: rgba(255, 255, 255, .1);
  color: #fff;
  border: none; cursor: pointer;
  width: 48px; height: 48px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem; line-height: 1;
  transition: background .2s ease, transform .15s ease;
  font-family: inherit;
  z-index: 1;
}
.gp-lightbox-btn:hover { background: rgba(255, 255, 255, .25); }
.gp-lightbox-btn:active { transform: scale(.94); }

.gp-lightbox-close { top: 1.25rem; right: 1.25rem; }
.gp-lightbox-prev  { left: 1.25rem; top: 50%; transform: translateY(-50%); }
.gp-lightbox-next  { right: 1.25rem; top: 50%; transform: translateY(-50%); }
.gp-lightbox-prev:active, .gp-lightbox-next:active { transform: translateY(-50%) scale(.94); }

.gp-lightbox-counter {
  position: absolute;
  bottom: 1.5rem; left: 50%; transform: translateX(-50%);
  color: rgba(255, 255, 255, .9);
  font: 500 .85rem/1 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: rgba(0, 0, 0, .55);
  padding: .5rem 1rem; border-radius: 999px;
  pointer-events: none;
}

@media (max-width: 640px) {
  .gp-lightbox-btn { width: 40px; height: 40px; font-size: 1.1rem; }
  .gp-lightbox-close { top: .75rem; right: .75rem; }
  .gp-lightbox-prev  { left: .5rem; }
  .gp-lightbox-next  { right: .5rem; }
}