:root { --sk-base: #e6e6e6; --sk-shine: #f4f4f4; }
@media (prefers-color-scheme: dark) { :root { --sk-base: #262626; --sk-shine: #343434; } }

img[data-sk], video[data-sk] {
  background-color: var(--sk-base);
  background-image: linear-gradient(100deg, transparent 20%, var(--sk-shine) 50%, transparent 80%);
  background-size: 200% 100%;
  background-repeat: no-repeat;
  animation: sk-shimmer 1.4s ease-in-out infinite;
}

@keyframes sk-shimmer {
  from { background-position: 150% 0; }
  to { background-position: -50% 0; }
}

/* gave up loading: static placeholder, no shimmer */
img[data-sk="error"] { animation: none; background-image: none; }

@media (prefers-reduced-motion: reduce) {
  img[data-sk], video[data-sk] { animation: none; background-image: none; }
}