/* Convite ML XV · botão flutuante de música (canto inferior direito) */

.music-btn {
  position: fixed;
  right: 16px;
  bottom: calc(16px + var(--sa-bottom));
  z-index: 29; /* abaixo das bottom sheets (31) e do backdrop: some quando uma sheet abre */
  width: 46px; height: 46px;
  display: grid; place-items: center;
  border-radius: 50%;
  color: var(--ouro-claro);
  background: rgba(30, 6, 18, .5);
  border: 1px solid rgba(200, 168, 107, .5);
  -webkit-backdrop-filter: blur(8px) saturate(1.2);
  backdrop-filter: blur(8px) saturate(1.2);
  cursor: pointer;
  opacity: 0; transform: scale(.85);
  pointer-events: none; /* só interage depois que o convite abre */
  transition: opacity .5s ease, transform .5s ease;
}
.music-btn.is-visible { opacity: 1; transform: scale(1); pointer-events: auto; }

.music-btn .ic {
  grid-area: 1 / 1;
  width: 22px; height: 22px;
  fill: none; stroke: currentColor;
  stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round;
}
.music-btn .ic-on { display: none; }
.music-btn .ic-off { display: block; opacity: .8; }
.music-btn.is-on .ic-on { display: block; }
.music-btn.is-on .ic-off { display: none; }

.music-halo {
  position: absolute; inset: -3px;
  border-radius: 50%;
  border: 2px solid rgba(200, 168, 107, .65);
  opacity: 0;
}
.music-btn.is-pulsing .music-halo { animation: musicPulse 1.8s ease-out infinite; }
.music-btn.is-pulsing { animation: musicNudge 1.8s ease-in-out infinite; }

@keyframes musicPulse {
  0%   { transform: scale(1);    opacity: .7; }
  100% { transform: scale(1.95); opacity: 0; }
}
@keyframes musicNudge {
  0%, 100% { box-shadow: 0 0 0 0 rgba(200, 168, 107, 0); }
  50%      { box-shadow: 0 0 16px 2px rgba(200, 168, 107, .4); }
}

@media (prefers-reduced-motion: reduce) {
  .music-btn.is-pulsing,
  .music-btn.is-pulsing .music-halo { animation: none; }
}