:root {
  --gold: #e7b64a;
  --gold-bright: #f4d27a;
  --gold-deep: #8a5f1c;
  --abyss: #060504;        /* fondo tras la portada */
  --eye-glow: #3fd4cf;     /* verde de los ojos de Cthulhu */
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html, body { height: 100%; }

body {
  background: var(--abyss);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  min-height: 100dvh;
  overflow: hidden;
}

/* La portada mantiene su proporción exacta (941 x 1672) y se ve entera,
   sin recortes, ocupando todo el alto disponible. */
.frame {
  position: relative;
  aspect-ratio: 941 / 1672;
  height: 100vh;
  height: 100dvh;
  max-width: 100vw;
  background-image: url("Portada_guarida.jpg");
  background-size: cover;
  background-position: center;
  box-shadow: 0 0 120px rgba(0, 0, 0, 0.9) inset;
}

/* Botón centrado en la parte inferior de la portada */
.download {
  position: absolute;
  left: 50%;
  bottom: 6%;
  transform: translateX(-50%);

  display: inline-flex;
  align-items: center;
  gap: 0.55em;

  font-family: "Cinzel", Georgia, "Times New Roman", serif;
  font-weight: 600;
  font-size: clamp(1rem, 3.2vw, 1.6rem);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  text-decoration: none;

  color: var(--gold-bright);
  padding: 0.7em 1.9em;
  border: 1.5px solid var(--gold);
  border-radius: 2px;
  background: linear-gradient(180deg,
              rgba(20, 15, 8, 0.72),
              rgba(8, 6, 3, 0.82));
  backdrop-filter: blur(2px);

  text-shadow: 0 0 10px rgba(231, 182, 74, 0.5);
  box-shadow:
    0 0 0 1px rgba(0, 0, 0, 0.4),
    0 6px 24px rgba(0, 0, 0, 0.6),
    0 0 22px rgba(231, 182, 74, 0.18);

  cursor: pointer;
  animation: breathe 4.5s ease-in-out infinite;
  transition: transform 0.2s ease, box-shadow 0.3s ease,
              border-color 0.3s ease, color 0.3s ease;
}

.download__icon {
  width: 1.1em;
  height: 1.1em;
}

.download:hover,
.download:focus-visible {
  color: #fff7e2;
  border-color: var(--gold-bright);
  transform: translateX(-50%) translateY(-3px);
  box-shadow:
    0 0 0 1px rgba(0, 0, 0, 0.4),
    0 10px 30px rgba(0, 0, 0, 0.7),
    0 0 34px rgba(231, 182, 74, 0.55),
    0 0 60px rgba(63, 212, 207, 0.18);
  outline: none;
  animation-play-state: paused;
}

.download:active {
  transform: translateX(-50%) translateY(-1px);
}

/* Latido tenue, como los ojos de la criatura */
@keyframes breathe {
  0%, 100% { box-shadow:
      0 0 0 1px rgba(0, 0, 0, 0.4),
      0 6px 24px rgba(0, 0, 0, 0.6),
      0 0 18px rgba(231, 182, 74, 0.14); }
  50% { box-shadow:
      0 0 0 1px rgba(0, 0, 0, 0.4),
      0 6px 24px rgba(0, 0, 0, 0.6),
      0 0 30px rgba(231, 182, 74, 0.32); }
}

@media (prefers-reduced-motion: reduce) {
  .download { animation: none; }
}