/* Mobile-first card-table layout. Cream, indigo, ochre, gold, crimson. */
:root {
  --bg: #16111c;
  --ink: #f6f0e4;
  --muted: #c4b8a4;
  --gold: #c9a227;
  --line: rgba(201, 162, 39, 0.35);
  --bar: rgba(22, 17, 28, 0.94);
  --gap: 0.55rem;
  --bar-h: 5.75rem;
  color-scheme: dark;
  font-family: -apple-system, system-ui, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html, body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
}
body {
  min-height: 100dvh;
  min-height: 100svh;
  padding-top: env(safe-area-inset-top);
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
  padding-bottom: 0;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.7rem 0 0.4rem;
  position: sticky;
  top: 0;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  z-index: 2;
}
h1 {
  margin: 0;
  font-size: 1.05rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 650;
}
h2 {
  margin: 1rem 0 0.55rem;
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--muted);
  font-weight: 600;
}

#signin { padding: 2.5rem 0 3rem; text-align: center; }
#signin-error { color: #e07a7a; }

a.btn, button {
  font: inherit;
  color: inherit;
}
a.btn {
  display: inline-block;
  padding: 0.85rem 1.4rem;
  min-height: 2.75rem;
  border-radius: 999px;
  background: var(--gold);
  color: #16111c;
  text-decoration: none;
  font-weight: 650;
}
#signout, #playpause {
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 999px;
  min-height: 2.5rem;
  min-width: 2.5rem;
  padding: 0.4rem 0.9rem;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
}

#player {
  padding-bottom: calc(var(--bar-h) + env(safe-area-inset-bottom) + 0.75rem);
}
#audio { display: none; }

.deck {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--gap);
}
@media (min-width: 420px) {
  .deck { grid-template-columns: repeat(4, 1fr); }
}
@media (min-width: 640px) {
  body { max-width: 42rem; margin: 0 auto; }
  .deck { grid-template-columns: repeat(5, 1fr); }
}

.card {
  position: relative;
  aspect-ratio: 3 / 4;
  margin: 0;
  padding: 0;
  border: 0;
  background: transparent;
  cursor: pointer;
  perspective: 1000px;
  -webkit-tap-highlight-color: transparent;
  border-radius: 0.45rem;
}
.card:focus-visible {
  outline: 2px solid var(--gold);
  outline-offset: 3px;
}
.card-inner {
  position: relative;
  display: block;
  width: 100%;
  height: 100%;
  transform-style: preserve-3d;
  transition: transform 0.6s cubic-bezier(0.2, 0.7, 0.2, 1);
}
.card.is-flipped .card-inner { transform: rotateY(180deg); }
.card.is-current {
  filter: drop-shadow(0 0 0.55rem color-mix(in srgb, var(--gold) 80%, white));
}
.card-back, .card-face {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: 0.4rem;
  /* Avoid a brief back-face flash on some WebKit builds */
  background: var(--bg);
}
.card-face { transform: rotateY(180deg); }

@media (prefers-reduced-motion: reduce) {
  .card-inner { transition: none; }
}

.nowbar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 5;
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas:
    "btn title time"
    "btn seek seek";
  gap: 0.2rem 0.8rem;
  align-items: center;
  padding: 0.6rem 1rem calc(0.6rem + env(safe-area-inset-bottom));
  background: var(--bar);
  border-top: 1px solid var(--line);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}
#playpause { grid-area: btn; width: 2.85rem; height: 2.85rem; padding: 0; font-size: 0.7rem; font-weight: 650; }
#now-playing {
  grid-area: title;
  margin: 0;
  font-size: 0.88rem;
  font-weight: 600;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
#time {
  grid-area: time;
  font-size: 0.72rem;
  font-variant-numeric: tabular-nums;
  color: var(--muted);
}
#seek {
  grid-area: seek;
  width: 100%;
  min-height: 1.25rem;
  accent-color: var(--gold);
}

/* Locked chapters: dimmed back, gold Adinkra-style seal, no flip. */
.card-back-side {
  position: absolute;
  inset: 0;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
}
.card-back-side .card-back {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 0.4rem;
}
.card.is-locked .card-back {
  filter: grayscale(0.55) brightness(0.68) saturate(0.7);
}
.card-lock {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  color: #e6c34a;
  pointer-events: none;
  text-align: center;
  background:
    radial-gradient(ellipse at center, rgba(22, 17, 28, 0.18) 0%, rgba(22, 17, 28, 0.42) 100%);
  border-radius: 0.4rem;
}
.card-lock-icon {
  width: 38%;
  max-width: 3.2rem;
  height: auto;
  filter: drop-shadow(0 0 0.35rem rgba(201, 162, 39, 0.55));
}
.card-lock-label {
  font-size: 0.58rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 650;
  color: #f3e2a0;
  text-shadow: 0 1px 2px rgba(22, 17, 28, 0.8);
}
.card.is-shake {
  animation: card-wobble 0.45s ease;
}
@keyframes card-wobble {
  0%, 100% { transform: rotate(0deg); }
  20% { transform: rotate(-3.2deg); }
  40% { transform: rotate(3.2deg); }
  60% { transform: rotate(-2deg); }
  80% { transform: rotate(2deg); }
}
@media (prefers-reduced-motion: reduce) {
  .card.is-shake { animation: none; }
}

.toast {
  position: fixed;
  left: 50%;
  bottom: calc(var(--bar-h) + env(safe-area-inset-bottom) + 0.6rem);
  transform: translateX(-50%) translateY(0.4rem);
  z-index: 6;
  max-width: calc(100% - 2rem);
  padding: 0.65rem 1rem;
  border-radius: 999px;
  background: #1a1630;
  color: #f6f0e4;
  border: 1px solid var(--gold);
  box-shadow: 0 0 0.8rem rgba(201, 162, 39, 0.28);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
}
.toast.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}
@media (prefers-reduced-motion: reduce) {
  .toast { transition: opacity 0.15s ease; }
}