:root {
  --primary: #1f2937;
  --primary-light: #f3f4f6;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --border: #e5e7eb;
  --text-primary: #111827;
  --text-secondary: #6b7280;
}
html.dark {
  --primary: #f3f4f6;
  --primary-light: #1f2937;
  --accent: #60a5fa;
  --accent-hover: #3b82f6;
  --border: #374151;
  --text-primary: #f3f4f6;
  --text-secondary: #d1d5db;
}
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background-color: var(--primary-light);
  color: var(--text-primary);
  transition: background-color .3s, color .3s;
  margin: 0;
  padding: 0;
}
img.lazy-load {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: loading 1.5s infinite;
}
.image-card {
  transition: all .3s ease;
}
.image-card:hover {
  transform: translateY(-4px);
}
.download-btn {
  cursor: pointer;
  transition: all .2s ease;
}
.share-btn {
  cursor: pointer;
  transition: all .2s ease;
}
@keyframes loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}
@media (max-width: 768px) {
  .grid {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)) !important;
  }
}
.smooth-transition {
  transition: all .3s cubic-bezier(0.4, 0, 0.2, 1);
}
.fade-in {
  animation: fadeIn .3s ease-in;
}
@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}