:root {
  --font: "Inter", "PingFang SC", "Microsoft YaHei UI", "Microsoft YaHei", system-ui, sans-serif;
  --fg: rgb(255 255 255 / 0.94);
  --fg-dim: rgb(255 255 255 / 0.62);
  --panel: rgb(16 20 28 / 0.42);
  --line: rgb(255 255 255 / 0.14);
  --accent: #9fd4ff;
  --radius: 18px;
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
  overflow: hidden;
  background: #070a10;
  color: var(--fg);
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

#view {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

button {
  font: inherit;
  color: inherit;
  cursor: pointer;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

/* ---------- 开场 ---------- */
.intro {
  position: fixed;
  inset: 0;
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 12px;
  padding: 24px;
  text-align: center;
  transition: opacity 0.7s var(--ease), transform 0.7s var(--ease), visibility 0.7s;
}

.intro h2 {
  margin: 0;
  font-size: clamp(2rem, 6vw, 3.6rem);
  font-weight: 650;
  letter-spacing: 0.04em;
  text-shadow: 0 2px 24px rgb(0 0 0 / 0.5);
}

.intro p {
  margin: 0;
  color: var(--fg-dim);
  text-shadow: 0 1px 10px rgb(0 0 0 / 0.6);
}

.intro .hint {
  font-size: 0.85rem;
}

.btn-primary {
  margin: 18px 0 6px;
  padding: 14px 30px;
  min-height: 48px;
  border: 1px solid rgb(255 255 255 / 0.35);
  border-radius: 999px;
  background: rgb(255 255 255 / 0.14);
  backdrop-filter: blur(10px);
  font-weight: 600;
  transition: background 0.2s, transform 0.2s var(--ease);
}

.btn-primary:hover {
  background: rgb(255 255 255 / 0.24);
}

.btn-primary:active {
  transform: scale(0.97);
}

.intro .loading {
  display: none;
  color: var(--fg);
}

body[data-state="loading"] .intro .loading {
  display: block;
  animation: pulse 1.1s ease-in-out infinite;
}

body[data-state="loading"] .btn-primary {
  opacity: 0.5;
  pointer-events: none;
}

body[data-state="ready"] .intro,
body[data-state="switching"] .intro {
  opacity: 0;
  visibility: hidden;
  transform: scale(1.04);
}

@keyframes pulse {
  50% {
    opacity: 0.45;
  }
}

/* ---------- 播放控制条：位于玻璃外侧，不被水滴遮挡 ---------- */
.dock {
  position: fixed;
  left: 50%;
  bottom: max(20px, env(safe-area-inset-bottom));
  width: min(920px, calc(100% - 32px));
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 10px 18px 10px 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  backdrop-filter: blur(18px) saturate(1.3);
  box-shadow: 0 10px 40px rgb(0 0 0 / 0.35);
  opacity: 0;
  visibility: hidden;
  transform: translate(-50%, 24px);
  transition: opacity 0.6s var(--ease) 0.9s, transform 0.6s var(--ease) 0.9s, visibility 0s 0.9s;
}

body[data-state="ready"] .dock,
body[data-state="switching"] .dock {
  opacity: 1;
  visibility: visible;
  transform: translate(-50%, 0);
}

.btn-icon {
  flex: none;
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  border: 0;
  border-radius: 50%;
  background: var(--fg);
  color: #0b0f16;
  transition: transform 0.2s var(--ease);
}

.btn-icon:active {
  transform: scale(0.94);
}

.btn-icon svg {
  width: 24px;
  height: 24px;
  fill: currentColor;
}

.btn-icon[data-state="paused"] .i-pause,
.btn-icon[data-state="playing"] .i-play {
  display: none;
}

.btn-ghost {
  flex: none;
  min-height: 40px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--fg-dim);
  font-size: 0.9rem;
}

.btn-ghost:hover {
  color: var(--fg);
  border-color: rgb(255 255 255 / 0.3);
}

.seek {
  flex: 1;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 10px;
}

.time {
  flex: none;
  min-width: 3.2em;
  font-size: 0.8rem;
  font-variant-numeric: tabular-nums;
  color: var(--fg-dim);
  text-align: center;
}

.slider {
  flex: none;
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--fg-dim);
}

.slider input {
  width: 84px;
}

input[type="range"] {
  flex: 1;
  min-width: 0;
  height: 24px;
  margin: 0;
  background: transparent;
  accent-color: var(--accent);
  cursor: pointer;
}

/* ---------- 拖放提示 ---------- */
.drop-hint {
  position: fixed;
  inset: 16px;
  display: grid;
  place-items: center;
  border: 2px dashed rgb(255 255 255 / 0.5);
  border-radius: 24px;
  background: rgb(10 14 22 / 0.45);
  font-size: 1.25rem;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.2s;
}

body.dragging .drop-hint {
  opacity: 1;
}

.toast {
  position: fixed;
  top: max(18px, env(safe-area-inset-top));
  left: 50%;
  max-width: calc(100% - 32px);
  margin: 0;
  padding: 10px 18px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgb(12 16 24 / 0.72);
  backdrop-filter: blur(12px);
  font-size: 0.9rem;
  transform: translate(-50%, -8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s, transform 0.3s var(--ease);
}

.toast.show {
  opacity: 1;
  transform: translate(-50%, 0);
}

@media (max-width: 720px) {
  .dock {
    flex-wrap: wrap;
    gap: 10px 14px;
    padding: 10px 14px;
  }

  .seek {
    order: 3;
    flex-basis: 100%;
  }

  .slider input {
    width: 64px;
  }

  #wipe {
    margin-left: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}