#intro-film {
  position: fixed;
  inset: 0;
  z-index: 60;
  height: 100dvh;
  overflow: hidden;
  background: #123f64;
  --film-width: min(100vw, 56.25dvh);
}
/* Both layers share the same video-height coordinate system. */
#intro-film { background: #123f64 url('assets/intro-v10-panorama.webp') center / cover no-repeat; }
#intro-film::before {
  content: "";
  position: absolute;
  left: 50%; top: 50%;
  transform: translate(-50%, -50%);
  width: calc(var(--film-width) * 4);
  height: min(100dvh, 177.777778vw);
  background: url('assets/intro-v10-panorama.webp') center / 100% 100% no-repeat;
}
#intro-film video {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: var(--film-width);
  height: min(100dvh, 177.777778vw);
  max-width: 100%;
  max-height: 100%;
  object-fit: contain;
  display: block;
  z-index: 1;
  mask-image: linear-gradient(to right, transparent, #000 2%, #000 98%, transparent);
}
.film-controls {
  position: absolute;
  z-index: 2;
  left: 0;
  right: 0;
  top: max(16px, env(safe-area-inset-top));
  display: flex;
  justify-content: space-between;
  gap: 15px;
  padding: 0 max(16px, env(safe-area-inset-right));
}
.film-controls button {
  background: #0b3156e8;
  border: 1px solid #e5c478;
  border-radius: 14px;
  color: #fff1c8;
  min-height: 46px;
  padding: 10px 16px;
  font: 700 14px 'Trebuchet MS', sans-serif;
  box-shadow: 0 3px 12px #0004;
}
.film-controls button:focus-visible { outline: 3px solid #8effef; outline-offset: 3px; }

@media (max-aspect-ratio: 9/16) {
  #intro-film { background: #123f64; }
  #intro-film video { mask-image: none; }
}