/* ==========================================================================
 * sections/piano.css — 04 / 听觉留白：曲目单 + 音符监视器 + 键盘容器
 * 依赖：tokens.css, base.css, components/section-header.css, components/keyboard.css
 * 逻辑见 js/modules/piano-player.js、wave-monitor.js、piano-keyboard.js
 * ========================================================================== */

.piano-section {
  padding: clamp(5rem, 9vw, 8rem) 0;
  background: linear-gradient(180deg, var(--bg-alabaster) 0%, var(--bg-sand-tint) 100%);
}
/* 滚动进入时微缩放展开，transform 由 js/modules/scroll-choreography.js 写入。
   注意：wave-monitor 用 clientWidth 量画布尺寸，正是为了不受这里的 scale 影响。 */
.piano-studio-card {
  background: var(--surface-card);
  border: 1px solid var(--border-strong);
  border-radius: 26px;
  padding: clamp(1.75rem, 4vw, 3.25rem);
  box-shadow: 0 32px 72px rgba(30, 42, 36, 0.1);
  will-change: transform;
}
.piano-top-grid {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: clamp(2rem, 4vw, 3.5rem);
  align-items: center;
  margin-bottom: 2.5rem;
}

/* ---------- 左侧：三首曲目单 ---------- */
.track-selector {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}
.track-card-btn {
  width: 100%;
  background: var(--bg-alabaster);
  border: 1px solid var(--border-subtle);
  border-radius: 14px;
  padding: 1.1rem 1.35rem;
  display: grid;
  grid-template-columns: 36px 1fr auto;
  gap: 0.85rem;
  align-items: center;
  text-align: left;
  cursor: pointer;
  color: var(--ink-main);
  transition: transform 0.4s var(--ease-out-expo), background 0.3s ease, border-color 0.3s ease, box-shadow 0.4s ease;
}
.track-card-btn.active {
  background: var(--forest-deep);
  color: var(--surface-card);
  border-color: var(--forest-deep);
  transform: translateX(10px);
  box-shadow: 0 14px 30px rgba(30, 42, 36, 0.16);
}
.t-idx {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--accent-sage);
}
.track-card-btn.active .t-idx {
  color: var(--accent-ochre);
}
.t-info strong {
  display: block;
  font-family: var(--font-serif-en);
  font-size: 1.3rem;
  font-weight: 600;
  line-height: 1.2;
}
.t-info span {
  font-size: 0.8rem;
  opacity: 0.75;
}
.t-badge {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.28rem 0.75rem;
  border-radius: 99px;
  border: 1px solid currentColor;
  text-transform: uppercase;
}

/* ---------------------------------------------------------------------------
   悬停态：仅限有指针的设备。
   手机点一下曲目会一直卡在 translateX(8px) 的偏移上，必须挡掉。
   --------------------------------------------------------------------------- */
@media (hover: hover) and (pointer: fine) {
  .track-card-btn:hover {
    transform: translateX(8px);
    border-color: var(--border-strong);
    box-shadow: 0 10px 24px rgba(30, 42, 36, 0.06);
  }
}

/* ---------- 右侧：实时音符谱面监视器 + 共振弦纹画布 ---------- */
.score-monitor-box {
  background: var(--forest-deep);
  color: var(--surface-card);
  border-radius: 20px;
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 270px;
  position: relative;
  overflow: hidden;
}
#noteWaveCanvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.55;
}
.monitor-header,
.live-note-stage,
.monitor-quote {
  position: relative;
  z-index: 2;
}
.monitor-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.25rem 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: rgba(250, 247, 242, 0.7);
  border-bottom: 1px solid rgba(250, 247, 242, 0.12);
  padding-bottom: 0.85rem;
}
.live-note-stage {
  margin: auto 0;
  padding: 1.5rem 0;
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.current-chord-display {
  font-family: var(--font-serif-en);
  font-style: italic;
  font-size: clamp(2.2rem, 3.8vw, 3.2rem);
  color: var(--accent-ochre);
  line-height: 1;
  transition: transform 0.15s var(--ease-out-expo);
}
.note-stream-ribbon {
  display: flex;
  gap: 0.45rem;
  flex-wrap: wrap;
  align-items: center;
}
.note-pill {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.22rem 0.55rem;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.08);
  color: rgba(255, 255, 255, 0.75);
  transition: all 0.2s var(--ease-out-expo);
}
.note-pill.current {
  background: var(--accent-terracotta);
  color: #fff;
  transform: scale(1.12) translateY(-2px);
}
.monitor-quote {
  font-family: var(--font-serif-zh);
  font-size: 0.86rem;
  color: rgba(250, 247, 242, 0.75);
  border-top: 1px solid rgba(250, 247, 242, 0.12);
  padding-top: 0.85rem;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.5rem;
}

/* ---------- 窄屏 ---------- */
@media (max-width: 960px) {
  .piano-top-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  .piano-studio-card {
    padding: 1.25rem 1.1rem;
    border-radius: 20px;
  }
  .piano-top-grid {
    gap: 1.5rem;
    margin-bottom: 1.75rem;
  }
  .track-selector {
    gap: 0.6rem;
  }
  .track-card-btn {
    padding: 0.9rem 1rem;
    grid-template-columns: 28px 1fr auto;
    gap: 0.6rem;
    border-radius: 12px;
  }
  .track-card-btn.active {
    transform: translateX(6px);
  }
  .t-idx {
    font-size: 0.7rem;
  }
  .t-info strong {
    font-size: 1.12rem;
  }
  .t-info span {
    font-size: 0.74rem;
    line-height: 1.5;
    display: block;
    margin-top: 0.15rem;
  }
  .t-badge {
    font-size: 0.6rem;
    padding: 0.2rem 0.5rem;
  }
  .score-monitor-box {
    padding: 1.15rem;
    min-height: 230px;
    border-radius: 16px;
  }
  .monitor-header {
    font-size: 0.66rem;
  }
  .live-note-stage {
    padding: 1.1rem 0;
    gap: 0.6rem;
  }
  .current-chord-display {
    font-size: 2rem;
  }
  .note-stream-ribbon {
    gap: 0.35rem;
  }
  .note-pill {
    font-size: 0.68rem;
    padding: 0.18rem 0.45rem;
  }
  .monitor-quote {
    font-size: 0.78rem;
  }
}