body.book-yyjf .audio-lab-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: end;
  padding: 28px 30px;
  border: 1px solid rgba(36, 74, 120, 0.18);
  border-left: 7px solid var(--brand);
  background: linear-gradient(120deg, #ffffff 0%, #edf4fb 72%, #fff3da 100%);
  box-shadow: var(--shadow);
}

body.book-yyjf .audio-lab-header h1 {
  max-width: 720px;
  margin: 0;
  color: var(--brand-strong);
  font-size: clamp(2rem, 4vw, 3.75rem);
  line-height: 0.98;
}

body.book-yyjf .audio-lab-header p {
  max-width: 720px;
  margin: 12px 0 0;
  color: #53667b;
}

body.book-yyjf .audio-signal {
  display: flex;
  align-items: end;
  gap: 5px;
  min-width: 116px;
  height: 74px;
  padding: 12px;
  border: 1px solid rgba(36, 74, 120, 0.2);
  background: rgba(255, 255, 255, 0.75);
}

body.book-yyjf .audio-signal span {
  flex: 1;
  height: 26%;
  background: var(--accent);
  transform-origin: bottom;
  animation: audio-signal-pulse 1.1s ease-in-out infinite alternate;
}

body.book-yyjf .audio-signal span:nth-child(2) { height: 58%; animation-delay: 0.1s; }
body.book-yyjf .audio-signal span:nth-child(3) { height: 88%; animation-delay: 0.2s; }
body.book-yyjf .audio-signal span:nth-child(4) { height: 48%; animation-delay: 0.3s; }
body.book-yyjf .audio-signal span:nth-child(5) { height: 72%; animation-delay: 0.4s; }
body.book-yyjf .audio-signal span:nth-child(6) { height: 34%; animation-delay: 0.5s; }

@keyframes audio-signal-pulse {
  from { transform: scaleY(0.62); opacity: 0.62; }
  to { transform: scaleY(1); opacity: 1; }
}

body.book-yyjf .audio-layout {
  display: grid;
  grid-template-columns: minmax(220px, 0.34fr) minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}

body.book-yyjf .audio-lesson-list {
  display: grid;
  gap: 8px;
  position: sticky;
  top: 94px;
}

body.book-yyjf .audio-lesson-button {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr);
  gap: 10px;
  align-items: center;
  width: 100%;
  min-height: 62px;
  padding: 10px 12px;
  color: var(--ink);
  text-align: left;
  border: 1px solid rgba(36, 74, 120, 0.16);
  border-left: 3px solid transparent;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.86);
  transition: border-color 180ms ease, background 180ms ease, transform 180ms ease;
}

body.book-yyjf .audio-lesson-button:hover,
body.book-yyjf .audio-lesson-button.active {
  border-left-color: var(--accent);
  border-color: rgba(36, 74, 120, 0.28);
  background: linear-gradient(105deg, var(--brand-soft), var(--accent-soft));
  transform: translateX(3px);
}

body.book-yyjf .audio-lesson-number {
  display: grid;
  place-items: center;
  width: 30px;
  aspect-ratio: 1;
  color: #fff;
  font: 700 12px/1 Consolas, "Courier New", monospace;
  background: var(--brand-strong);
  border-radius: 50%;
}

body.book-yyjf .audio-lesson-button strong,
body.book-yyjf .audio-lesson-button small {
  display: block;
}

body.book-yyjf .audio-lesson-button strong {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

body.book-yyjf .audio-lesson-button small {
  margin-top: 4px;
  color: var(--muted);
  font-size: 12px;
}

body.book-yyjf .audio-panel {
  min-width: 0;
  padding: 26px;
  border: 1px solid rgba(36, 74, 120, 0.18);
  border-top: 5px solid var(--brand);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: var(--shadow);
}

body.book-yyjf .audio-panel-head {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: start;
  margin-bottom: 22px;
}

body.book-yyjf .audio-panel-head h2 {
  margin: 0;
  color: var(--brand-strong);
}

body.book-yyjf .audio-panel-head p {
  max-width: 620px;
  margin: 8px 0 0;
  color: var(--muted);
}

body.book-yyjf .audio-speed-control {
  display: grid;
  gap: 5px;
  min-width: 120px;
  color: var(--muted);
  font-size: 12px;
}

body.book-yyjf .audio-speed-control select {
  min-height: 36px;
  padding: 0 10px;
  color: var(--ink);
  border: 1px solid rgba(36, 74, 120, 0.25);
  border-radius: 4px;
  background: #fff;
}

body.book-yyjf .audio-clip-list {
  display: grid;
  gap: 12px;
}

body.book-yyjf .audio-clip-list-compact {
  gap: 8px;
  margin-top: 14px;
}

body.book-yyjf .audio-clip {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr) minmax(240px, auto);
  gap: 14px;
  align-items: center;
  padding: 16px;
  border: 1px solid rgba(36, 74, 120, 0.16);
  background: #fbfdff;
}

body.book-yyjf .audio-clip-number {
  align-self: start;
  color: var(--accent);
  font: 700 18px/1 Consolas, "Courier New", monospace;
}

body.book-yyjf .audio-clip-compact {
  grid-template-columns: 34px minmax(0, 1fr) minmax(180px, auto);
  gap: 10px;
  padding: 11px 12px;
}

body.book-yyjf .audio-clip-compact .audio-sentence {
  font-size: 15px;
}

body.book-yyjf .audio-clip-compact .audio-translation {
  margin-top: 3px;
  font-size: 12px;
}

body.book-yyjf .lesson-audio-head {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 14px;
}

body.book-yyjf .lesson-audio-head h3 {
  margin: 0;
}

body.book-yyjf .audio-clip-label {
  margin: 0 0 7px;
  color: var(--brand-strong);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

body.book-yyjf .audio-sentence {
  margin: 0;
  color: var(--ink);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.45;
}

body.book-yyjf .audio-translation {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 13px;
}

body.book-yyjf .audio-clip-actions {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 38px;
  gap: 8px;
  align-items: center;
}

body.book-yyjf .audio-player {
  width: 100%;
  min-width: 0;
  height: 38px;
}

body.book-yyjf .audio-speak-button {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  padding: 0;
  color: var(--brand-strong);
  border: 1px solid rgba(36, 74, 120, 0.24);
  border-radius: 4px;
  background: var(--brand-soft);
}

body.book-yyjf .audio-speak-button:hover {
  color: #fff;
  background: var(--brand);
}

body.book-yyjf .audio-disclosure,
body.book-yyjf .audio-coach-note {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-top: 18px;
  padding: 12px 14px;
  color: #53667b;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  font-size: 13px;
  line-height: 1.7;
}

body.book-yyjf .audio-coach-note .lucide {
  flex: 0 0 auto;
  width: 18px;
  height: 18px;
  margin-top: 3px;
}

body.book-yyjf .audio-panel-actions {
  margin-top: 20px;
}

body.book-yyjf .audio-quiz-panel {
  border-top: 5px solid var(--accent);
}

body.book-yyjf .audio-quiz-question .question-audio {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 38px;
  gap: 8px;
  align-items: center;
  margin: 16px 0;
  padding: 10px;
  border: 1px solid rgba(36, 74, 120, 0.16);
  background: #f5f8fd;
}

body.book-yyjf .audio-quiz-question .question-audio audio {
  width: 100%;
  height: 36px;
}

body.book-yyjf .audio-quiz-question .question-audio button {
  width: 38px;
  height: 38px;
}

@media (max-width: 860px) {
  body.book-yyjf .audio-lab-header {
    grid-template-columns: 1fr;
    padding: 22px;
  }

  body.book-yyjf .audio-signal {
    width: 100%;
  }

  body.book-yyjf .audio-layout {
    grid-template-columns: 1fr;
  }

  body.book-yyjf .audio-lesson-list {
    position: static;
    display: flex;
    overflow-x: auto;
    padding-bottom: 4px;
  }

  body.book-yyjf .audio-lesson-button {
    flex: 0 0 188px;
  }

  body.book-yyjf .audio-panel-head {
    display: grid;
  }

  body.book-yyjf .audio-clip {
    grid-template-columns: 34px minmax(0, 1fr);
  }

  body.book-yyjf .audio-clip-compact {
    grid-template-columns: 34px minmax(0, 1fr);
  }

  body.book-yyjf .audio-clip-actions {
    grid-column: 2;
  }

  body.book-yyjf .lesson-audio-head {
    display: grid;
  }
}

@media (max-width: 520px) {
  body.book-yyjf .audio-panel {
    padding: 18px 14px;
  }

  body.book-yyjf .audio-sentence {
    font-size: 16px;
  }

  body.book-yyjf .audio-clip-actions {
    grid-template-columns: minmax(0, 1fr) 36px;
  }
}

@media (prefers-reduced-motion: reduce) {
  body.book-yyjf .audio-signal span {
    animation: none;
  }
}