.art-gallery-wall-gallery-wrapper {
  max-width: 1260px; /* 7 cột x 180px + 6 x 15px gap = 1260px */
  margin: 0 auto;
  padding: 20px;
}

.art-gallery-wall-masonry-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 15px;
  justify-content: center; /* 👈 căn giữa flex item */
}

.art-gallery-wall-grid-item {
  width: 180px;
  box-sizing: border-box;
}
@media (max-width: 1200px) {
  .art-gallery-wall-grid-item {
    width: 25%; /* 4 cột */
  }
}

@media (max-width: 768px) {
  .art-gallery-wall-grid-item {
    width: 50%; /* 2 cột */
  }
}

.art-gallery-wall-grid-item img {
  width: 100%;
  height: auto;
  border-radius: 6px;
  cursor: zoom-in;
}

/* Lightbox popup */
#art-gallery-wall-lightbox {
  display: none;
  position: fixed;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(0,0,0,0.85);
  justify-content: center;
  align-items: center;
  z-index: 9999;
}

#art-gallery-wall-lightbox img {
  max-width: 90%;
  max-height: 90%;
  border-radius: 6px;
}

.art-gallery-wall-close-btn {
  position: absolute;
  top: 30px;
  right: 40px;
  font-size: 32px;
  color: white;
  cursor: pointer;
  z-index: 10000;
}

.art-gallery-wall-loading {
  text-align: center;
  font-size: 16px;
  color: #888;
  margin-top: 20px;
}

/* Navigation buttons */
.art-gallery-wall-prev-btn,
.art-gallery-wall-next-btn {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 40px;
  color: white;
  cursor: pointer;
  z-index: 10001;
  padding: 10px;
  background: rgba(0, 0, 0, 0.3);
  border-radius: 8px;
  user-select: none;
}

.art-gallery-wall-prev-btn { left: 30px; }
.art-gallery-wall-next-btn { right: 30px; }

.art-gallery-wall-prev-btn:hover,
.art-gallery-wall-next-btn:hover {
  background: rgba(255,255,255,0.1);
}

.art-gallery-wall-loading {
  text-align: center;
  padding: 20px;
}

.art-gallery-wall-spinner {
  width: 40px;
  height: 40px;
  border: 4px solid #ccc;
  border-top: 4px solid #333;
  border-radius: 50%;
  animation: art-gallery-wall-spin 0.8s linear infinite;
  margin: 0 auto;
}

@keyframes art-gallery-wall-spin {
  0%   { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}