/* Top only: a faint presence in the empty upper part of the hero background. */
.entrance-page .botanical-hero > .rd-ambient-light {
  --rd-ambient-start: 0.04;
  --rd-ambient-end: 0.055;
  --rd-ambient-x: 4px;
  --rd-ambient-y: 3px;
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background: radial-gradient(ellipse 52% 30% at 18% 0%,
    rgba(255, 246, 222, 0.30), rgba(255, 246, 222, 0.12) 40%, transparent 72%);
  opacity: var(--rd-ambient-start);
  animation: rd-top-ambient-air 22s ease-in-out infinite alternate;
}

:is(.theme-dim, [data-theme="moon"], [data-theme="dark"])
  .entrance-page .botanical-hero > .rd-ambient-light {
  --rd-ambient-start: 0.025;
  --rd-ambient-end: 0.032;
  --rd-ambient-x: 3px;
  --rd-ambient-y: 2px;
  background: radial-gradient(ellipse 52% 30% at 18% 0%,
    rgba(204, 224, 239, 0.22), rgba(204, 224, 239, 0.08) 40%, transparent 72%);
  animation-duration: 26s;
}

@keyframes rd-top-ambient-air {
  from { opacity: var(--rd-ambient-start); transform: translate(0, 0); }
  to { opacity: var(--rd-ambient-end); transform: translate(var(--rd-ambient-x), var(--rd-ambient-y)); }
}

@media (prefers-reduced-motion: reduce) {
  .entrance-page .botanical-hero > .rd-ambient-light {
    display: none;
    animation: none;
    opacity: 0;
    transform: none;
  }
}