/* ── Global interaction states ──────────────────────────── */
/* Keyboard navigation must be visible (WCAG 2.4.7) */
:focus-visible {
  outline: 2px solid var(--c-primary);
  outline-offset: 2px;
  border-radius: var(--r-sm);
}

/* Respect user motion preferences (WCAG 2.3.3) */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Dark-theme scrollbars (chain rack, stems) */
.chain-modules::-webkit-scrollbar,
.stems-panel::-webkit-scrollbar,
.meters-panel::-webkit-scrollbar { width: 8px; }
.chain-modules::-webkit-scrollbar-track,
.stems-panel::-webkit-scrollbar-track,
.meters-panel::-webkit-scrollbar-track { background: transparent; }
.chain-modules::-webkit-scrollbar-thumb,
.stems-panel::-webkit-scrollbar-thumb,
.meters-panel::-webkit-scrollbar-thumb {
  background: var(--c-bg-overlay);
  border-radius: var(--r-full);
}
.chain-modules::-webkit-scrollbar-thumb:hover,
.stems-panel::-webkit-scrollbar-thumb:hover,
.meters-panel::-webkit-scrollbar-thumb:hover { background: var(--c-text-3); }

/* ── App shell ──────────────────────────────────────────── */
#app {
  display: grid;
  grid-template-rows: var(--header-h) var(--analysis-h) 1fr var(--transport-h);
  grid-template-columns: 1fr var(--chain-w);
  height: 100dvh;
  overflow: hidden;
}


/* ── Header ─────────────────────────────────────────────── */
.header {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  padding: 0 var(--sp-5);
  background: var(--c-bg-surface);
  border-bottom: 1px solid var(--c-border);
  z-index: 10;
}

.logo {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--c-primary);
  letter-spacing: -0.5px;
  flex-shrink: 0;
}

.logo span { color: var(--c-text-2); font-weight: 400; }

/* Upload drop zone */
.upload-zone {
  flex: 1;
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-4);
  border: 1px dashed var(--c-border);
  border-radius: var(--r-md);
  cursor: pointer;
  transition: border-color var(--dur-fast), background var(--dur-fast);
  max-width: 480px;
  position: relative;
  overflow: hidden;
}

.upload-zone:hover, .upload-zone.drag-over {
  border-color: var(--c-primary);
  background: var(--c-primary-dim);
}

.upload-zone input[type="file"] {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
  width: 100%;
}

.upload-icon { color: var(--c-primary); font-size: 18px; }

.upload-text { font-size: var(--text-sm); color: var(--c-text-2); }
.upload-text strong { color: var(--c-text-1); }

.upload-formats { font-size: var(--text-xs); color: var(--c-text-3); }

.upload-filename {
  font-size: var(--text-sm);
  color: var(--c-text-1);
  font-weight: 500;
}

.header-actions { display: flex; align-items: center; gap: var(--sp-3); margin-left: auto; }

/* A/B toggle */
.ab-toggle {
  display: flex;
  align-items: center;
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  overflow: hidden;
}

.ab-btn {
  padding: 6px 14px;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--c-text-2);
  transition: color var(--dur-fast), background var(--dur-fast);
}

.ab-btn:hover:not(.active) { color: var(--c-text-1); background: var(--c-bg-overlay); }

.ab-btn.active {
  color: var(--c-text-1);
  background: var(--c-primary);
}

/* 存1/存2 slots — dimmer until filled */
.ab-btn.snap-btn { color: var(--c-text-3); opacity: 0.6; border-left: 1px solid var(--c-border); }
.ab-btn.snap-btn:hover { opacity: 1; color: var(--c-text-1); background: var(--c-bg-overlay); }
.ab-btn.snap-btn.snap-filled { opacity: 1; color: var(--c-primary); }

.header-btn {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: 6px var(--sp-4);
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  font-size: var(--text-sm);
  color: var(--c-text-2);
  transition: border-color var(--dur-fast), color var(--dur-fast);
}

.header-btn:hover:not(:disabled) { border-color: var(--c-border-hover); color: var(--c-text-1); }

.header-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.export-bitdepth {
  padding: 6px var(--sp-2);
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  font-size: var(--text-sm);
  color: var(--c-text-2);
  cursor: pointer;
}
.export-bitdepth:hover { border-color: var(--c-border-hover); color: var(--c-text-1); }

.header-btn.primary {
  background: var(--c-primary);
  border-color: var(--c-primary);
  color: #fff;
}

.header-btn.primary:hover:not(:disabled) { background: var(--c-primary-h); border-color: var(--c-primary-h); }
.header-btn.primary:disabled { opacity: 0.4; cursor: not-allowed; }

/* ── Analysis bar ───────────────────────────────────────── */
.analysis-bar {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  padding: 0 var(--sp-5);
  background: var(--c-bg-elevated);
  border-bottom: 1px solid var(--c-border);
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  overflow: hidden;
}

.analysis-pill {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: 3px var(--sp-3);
  background: var(--c-bg-overlay);
  border-radius: var(--r-full);
  border: 1px solid var(--c-border);
  white-space: nowrap;
  transition: border-color var(--dur-fast);
}

.analysis-pill:hover { border-color: var(--c-border-hover); }

.analysis-label { color: var(--c-text-3); letter-spacing: 0.03em; }
.analysis-value {
  color: var(--c-text-1);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  transition: color var(--dur-mid);
}
.analysis-value.updated {
  animation: flash-value 0.5s var(--ease-out);
}

/* Confidence bar (thin underline inside pill) */
.analysis-conf-track {
  display: block;
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--c-border);
  border-radius: 0 0 var(--r-full) var(--r-full);
  overflow: hidden;
}
.analysis-conf-fill {
  display: block;
  height: 100%;
  width: 0%;
  background: currentColor;
  transition: width var(--dur-slow) var(--ease-out);
}
/* Pills with confidence bar need relative positioning */
.analysis-pill {
  position: relative;
}

.analysis-pill.genre .analysis-value  { color: var(--c-primary); }
.analysis-pill.genre .analysis-conf-fill { background: var(--c-primary); }
.analysis-pill.bpm .analysis-value    { color: var(--c-blue); }
.analysis-pill.bpm .analysis-conf-fill   { background: var(--c-blue); }
.analysis-pill.key .analysis-value    { color: var(--c-green); }
.analysis-pill.key .analysis-conf-fill   { background: var(--c-green); }
.analysis-pill.lufs .analysis-value   { color: var(--c-orange); }

.analysis-sep { color: var(--c-border); }

.analysis-status {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  color: var(--c-text-3);
}

/* Status text turns red on error so failures are visually distinct */
#status-text.status-error { color: var(--c-primary-h); font-weight: 600; }

.analysis-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--c-text-3);
}

.analysis-dot.active { background: var(--c-green); animation: pulse 2s ease infinite; }
.analysis-dot.processing { background: var(--c-orange); animation: pulse 0.8s ease infinite; }

/* ── Workspace ──────────────────────────────────────────── */
.workspace {
  grid-column: 1;
  grid-row: 3;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-height: 0;
  min-width: 0;
}

/* Main waveform */
.main-waveform-panel {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
  padding: var(--sp-4) var(--sp-4) 0;
  background: var(--c-bg-base);
}

.waveform-toolbar {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-bottom: var(--sp-3);
  min-width: 0;
}

.waveform-label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.waveform-zoom {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  margin-left: auto;
  padding: 3px;
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.03);
  flex-shrink: 0;
}

.waveform-zoom-label {
  padding: 0 var(--sp-2);
  color: var(--c-text-3);
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.12em;
}

.icon-btn {
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--r-sm);
  color: var(--c-text-3);
  transition: color var(--dur-fast), background var(--dur-fast);
}

.icon-btn:hover:not(:disabled) { color: var(--c-text-1); background: var(--c-bg-elevated); }
.icon-btn:disabled { opacity: 0.3; cursor: not-allowed; }

.waveform-zoom .icon-btn {
  border: 1px solid transparent;
  background: var(--c-bg-input);
  color: var(--c-text-2);
}
.waveform-zoom .icon-btn:hover:not(:disabled) {
  border-color: var(--c-border-hover);
  background: var(--c-bg-overlay);
}
.waveform-zoom-value {
  min-width: 38px;
  padding: 0 var(--sp-2);
  color: var(--c-text-1);
  font-family: var(--font-mono);
  font-size: var(--text-xs);
  font-variant-numeric: tabular-nums;
  text-align: center;
}

#waveform-main {
  flex: 1;
  min-height: 0;
  border-radius: var(--r-md);
  overflow: hidden;
  background: var(--c-bg-surface);
  position: relative;
}

/* Empty state: shown before any file is loaded */
.waveform-empty {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-3);
  pointer-events: none;
  user-select: none;
}

.waveform-empty-bars {
  display: flex;
  align-items: flex-end;
  gap: 3px;
  height: 36px;
  opacity: 0.18;
}

.waveform-empty-bar {
  width: 3px;
  background: var(--c-waveform);
  border-radius: 2px;
}

.waveform-empty-text {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* Idle shimmer scan line on the empty waveform */
.waveform-empty::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 40%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(232,0,60,0.04), transparent);
  animation: waveform-idle-scan 3s linear infinite;
  pointer-events: none;
}

/* ── Album panel (sequence for DDP master) ──────────────── */
.album-panel {
  height: var(--stems-h);
  flex-shrink: 0;
  overflow-y: auto;
  border-top: 1px solid var(--c-border);
  background: var(--c-bg-surface);
}
.album-head {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  padding: var(--sp-2) var(--sp-4);
  border-bottom: 1px solid var(--c-border);
}
.album-title-label {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-right: auto;   /* push count + export button to the right */
}
#album-export-btn, #album-align-btn { padding: 4px var(--sp-3); font-size: var(--text-xs); }
.album-target { font-size: var(--text-xs); color: var(--c-text-3); display: flex; align-items: center; gap: 4px; }
.album-target input {
  width: 56px; padding: 3px 6px;
  background: var(--c-bg-input); border: 1px solid var(--c-border);
  border-radius: var(--r-sm); font-size: var(--text-xs);
  font-family: var(--font-mono); color: var(--c-text-1);
}
.album-count { font-size: var(--text-xs); color: var(--c-text-3); font-family: var(--font-mono); }

.album-cols, .album-row {
  display: grid;
  grid-template-columns: 32px 1fr 72px 84px 64px 120px 88px;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-4);
}
.album-cols {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  border-bottom: 1px solid var(--c-border);
}
.album-row {
  border-bottom: 1px solid var(--c-border);
  font-size: var(--text-sm);
  transition: background var(--dur-fast);
}
.album-row:hover { background: var(--c-bg-elevated); }
.album-row .ac-num { font-family: var(--font-mono); color: var(--c-text-3); }
.album-row .ac-title { color: var(--c-text-1); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.album-row .ac-lufs { font-family: var(--font-mono); font-variant-numeric: tabular-nums; color: var(--c-text-2); }
.album-row input[type="number"] {
  width: 100%;
  padding: 3px 6px;
  background: var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  color: var(--c-text-1);
}
.album-row input.ac-isrc {
  width: 100%;
  padding: 3px 6px;
  background: var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  color: var(--c-text-1);
  letter-spacing: 0.04em;
}
.album-row input.ac-isrc::placeholder { color: var(--c-text-3); letter-spacing: 0; }
.album-row .ac-ops { display: flex; gap: 4px; justify-content: flex-end; }
.album-op-btn {
  width: 22px; height: 22px;
  display: flex; align-items: center; justify-content: center;
  border-radius: var(--r-sm);
  border: 1px solid var(--c-border);
  color: var(--c-text-3);
  font-size: 11px;
  transition: all var(--dur-fast);
}
.album-op-btn:hover:not(:disabled) { border-color: var(--c-border-hover); color: var(--c-text-1); }
.album-op-btn:disabled { opacity: 0.3; cursor: not-allowed; }
.album-op-btn.remove:hover { border-color: var(--c-primary); color: var(--c-primary); }

.album-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 140px;
  gap: var(--sp-2);
  color: var(--c-text-3);
  text-align: center;
  padding: 0 var(--sp-6);
}
.album-empty-icon { font-size: 28px; opacity: 0.4; }
.album-empty-text { font-size: var(--text-sm); max-width: 420px; }

/* Stems panel */
.stems-panel {
  height: var(--stems-h);
  flex-shrink: 0;
  overflow-y: auto;
  border-top: 1px solid var(--c-border);
  background: var(--c-bg-surface);
}

.stems-header {
  display: flex;
  align-items: center;
  padding: var(--sp-2) var(--sp-4);
  border-bottom: 1px solid var(--c-border);
  font-size: var(--text-xs);
  color: var(--c-text-3);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  gap: var(--sp-4);
}

.stems-header-spacer { width: 180px; flex-shrink: 0; }
.stems-header-waveform { flex: 1; }
.stems-header-controls { width: 120px; flex-shrink: 0; text-align: right; }

.stem-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 160px;
  gap: var(--sp-3);
  color: var(--c-text-3);
}

.stem-empty-icon { font-size: 32px; opacity: 0.3; }
.stem-empty-text { font-size: var(--text-sm); }

/* Stem track */
.stem-track {
  display: flex;
  align-items: center;
  height: 38px;
  border-bottom: 1px solid var(--c-border);
  transition: background var(--dur-fast);
}

.stem-track:hover { background: var(--c-bg-elevated); }
.stem-track.muted { opacity: 0.4; }

.stem-info {
  width: 180px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: 0 var(--sp-4);
}

.stem-color-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.stem-icon { font-size: 14px; }
.stem-name { font-size: var(--text-sm); color: var(--c-text-1); font-weight: 500; }
.stem-type { font-size: var(--text-xs); color: var(--c-text-3); }

.stem-waveform {
  flex: 1;
  height: 100%;
  overflow: hidden;
  position: relative;
}

.stem-controls {
  width: 120px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: var(--sp-2);
  padding: 0 var(--sp-3);
}

.stem-vol {
  width: 60px;
  height: 3px;
  accent-color: var(--c-primary);
  cursor: pointer;
}

.stem-btn {
  width: 24px;
  height: 24px;
  border-radius: var(--r-sm);
  font-size: 10px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--c-border);
  color: var(--c-text-3);
  transition: all var(--dur-fast);
}

.stem-btn:hover { border-color: var(--c-border-hover); color: var(--c-text-1); }
.stem-btn.active-mute { background: var(--c-text-3); color: var(--c-bg-base); border-color: var(--c-text-3); }
.stem-btn.active-solo { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }

/* ── Chain panel (right sidebar) ────────────────────────── */
.chain-panel {
  grid-column: 2;
  grid-row: 3;
  display: flex;
  flex-direction: column;
  background: var(--c-bg-surface);
  border-left: 1px solid var(--c-border);
  overflow: hidden;
  min-height: 0;
}

.chain-header {
  display: flex;
  align-items: center;
  padding: var(--sp-3) var(--sp-4);
  border-bottom: 1px solid var(--c-border);
  gap: var(--sp-3);
}

.chain-title {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--c-text-2);
}

.preset-select {
  flex: 1;
  padding: 3px var(--sp-3);
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  color: var(--c-text-2);
  cursor: pointer;
}

.chain-modules {
  flex: 1 1 56%;
  min-height: 220px;
  overflow-y: auto;
  padding: var(--sp-3);
  display: flex;
  flex-direction: column;
  gap: var(--sp-2);
}

/* Module card */
.module-card {
  background: var(--c-bg-elevated);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  overflow: hidden;
  transition: border-color var(--dur-fast), box-shadow var(--dur-fast);
  flex-shrink: 0;  /* flex children compress before the rack scrolls — never squash cards */
}

.module-card:hover:not(.unimplemented) { border-color: var(--c-border-hover); }

/* Enabled modules get an accent left edge — signal chain at a glance */
.module-card.active {
  border-color: var(--c-primary-glow);
  box-shadow: inset 3px 0 0 var(--c-primary);
}

/* Unimplemented modules (第二期): visibly inert, honest about status */
.module-card.unimplemented {
  opacity: 0.5;
  filter: saturate(0.2);
}
.module-card.unimplemented .knob-wrap { pointer-events: none; }
.module-card.unimplemented .module-toggle { cursor: not-allowed; }

.phase-badge {
  display: inline-block;
  font-size: 9px;
  font-weight: 600;
  letter-spacing: 0.05em;
  color: var(--c-orange);
  border: 1px solid var(--c-orange);
  border-radius: var(--r-sm);
  padding: 0 4px;
  margin-left: 4px;
  vertical-align: middle;
}

.module-card.bypassed {
  opacity: 0.42;
  filter: saturate(0.3);
  border-style: dashed;
}
.module-card.bypassed .module-head::after {
  content: 'BYPASS';
  font-size: 9px;
  letter-spacing: 0.1em;
  color: var(--c-text-3);
  margin-left: auto;
  padding-right: var(--sp-3);
}

.module-head {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-3);
  cursor: pointer;
}

.module-toggle {
  width: 28px;
  height: 14px;
  position: relative;
  cursor: pointer;
  flex-shrink: 0;
}

.module-toggle input { opacity: 0; width: 0; height: 0; }

.module-toggle-track {
  position: absolute;
  inset: 0;
  background: var(--c-bg-overlay);
  border-radius: var(--r-full);
  border: 1px solid var(--c-border);
  transition: background var(--dur-fast);
}

.module-toggle-thumb {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 8px;
  height: 8px;
  background: var(--c-text-3);
  border-radius: 50%;
  transition: transform var(--dur-fast), background var(--dur-fast);
}

.module-toggle input:checked ~ .module-toggle-track { background: var(--c-primary-muted); border-color: var(--c-primary); }
.module-toggle input:checked ~ .module-toggle-thumb { transform: translateX(14px); background: var(--c-primary); }

.module-name { font-size: var(--text-sm); font-weight: 600; color: var(--c-text-1); flex: 1; }
.module-name-cn { font-size: var(--text-xs); color: var(--c-text-3); }

.module-expand { color: var(--c-text-3); font-size: 10px; transition: transform var(--dur-fast); }
.module-card.expanded .module-expand { transform: rotate(180deg); }

.module-body { padding: var(--sp-3); border-top: 1px solid var(--c-border); display: none; }
.module-card.expanded .module-body { display: block; }

/* Meters panel in chain */
.meters-panel {
  border-top: 1px solid var(--c-border);
  padding: var(--sp-3);
  flex: 1 1 44%;
  min-height: 230px;
  overflow-y: auto;
  display: grid;
  grid-template-columns: minmax(108px, 0.78fr) minmax(0, 1.22fr);
  grid-template-areas:
    "title title"
    "readings readings"
    "corr corr"
    "gonio graph"
    "gonio platforms";
  align-content: start;
  gap: var(--sp-3);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.018), transparent 120px),
    var(--c-bg-surface);
}

.meters-title {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0;
  grid-area: title;
}

/* Stereo correlation meter — needle moves across a −1…+1 track */
.corr-meter { margin-bottom: 0; grid-area: corr; }
.corr-meter-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}
.corr-meter-title {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.corr-meter-value {
  font-size: var(--text-sm);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--c-text-2);
}
.corr-meter-value.warn { color: var(--c-primary); }   /* anti-phase danger */
.corr-meter-track {
  position: relative;
  height: 8px;
  background: linear-gradient(90deg,
    var(--c-primary) 0%, var(--c-orange) 35%, var(--c-green) 50%, var(--c-blue) 100%);
  border-radius: 4px;
  opacity: 0.5;
}
.corr-meter-zero {
  position: absolute;
  left: 50%; top: -2px; bottom: -2px;
  width: 1px;
  background: var(--c-text-3);
  opacity: 0.5;
}
.corr-meter-needle {
  position: absolute;
  top: -2px; bottom: -2px;
  left: 50%;
  width: 3px;
  margin-left: -1.5px;
  background: var(--c-text-1);
  border-radius: 2px;
  transition: left 0.1s linear;
  box-shadow: 0 0 4px rgba(0,0,0,0.6);
}
.corr-meter-scale {
  display: flex;
  justify-content: space-between;
  font-size: 9px;
  color: var(--c-text-3);
  font-family: var(--font-mono);
  margin-top: 2px;
}

.gonio-meter { margin-bottom: 0; grid-area: gonio; min-width: 0; }
.gonio-meter-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}
.gonio-meter-title {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.gonio-wrap {
  width: 100%;
  aspect-ratio: 1 / 1;
  min-height: 108px;
  background: radial-gradient(circle at 50% 50%, rgba(78,205,196,0.08), transparent 64%), var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  overflow: hidden;
  box-shadow: inset 0 0 24px rgba(0,0,0,0.45);
}
.gonio-wrap canvas { display: block; width: 100%; height: 100%; }

.loudness-graph-meter { margin-bottom: 0; grid-area: graph; min-width: 0; }
.loudness-graph-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}
.loudness-graph-title {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.loudness-graph-wrap {
  width: 100%;
  height: 72px;
  background: var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  overflow: hidden;
}
.loudness-graph-wrap canvas { display: block; width: 100%; height: 100%; }

.lufs-platforms {
  grid-area: platforms;
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 0;
  padding: var(--sp-2);
  background: var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
}

.platform-row {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  font-size: 9px;
  font-family: var(--font-mono);
}

.platform-name { width: 54px; color: var(--c-text-2); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.platform-target { width: 43px; color: var(--c-text-3); white-space: nowrap; }

.platform-bar-wrap {
  flex: 1;
  height: 6px;
  background: var(--c-bg-overlay);
  border-radius: 3px;
  overflow: hidden;
}

.platform-bar { height: 100%; border-radius: 3px; transition: width 0.1s linear; }
.platform-bar.ok { background: var(--c-green); }
.platform-bar.warn { background: var(--c-orange); }
.platform-bar.over { background: var(--c-primary); }

.platform-status { font-size: 10px; width: 12px; text-align: center; }

.lufs-readings {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--sp-2);
  margin-bottom: 0;
  grid-area: readings;
}

/* Recessed LCD-style meter cells — the focal instrument cluster */
.lufs-reading {
  background: var(--c-bg-input);
  border: 1px solid var(--c-border);
  border-radius: var(--r-md);
  padding: var(--sp-2) var(--sp-3);
  text-align: center;
  box-shadow: inset 0 2px 6px rgba(0,0,0,0.5);
  position: relative;
  overflow: hidden;
}

/* Thin top accent line lights up when a live value is present */
.lufs-reading::before {
  content: '';
  position: absolute;
  top: 0; left: 20%; right: 20%;
  height: 2px;
  background: var(--c-text-3);
  opacity: 0.25;
  border-radius: 0 0 2px 2px;
  transition: background var(--dur-mid), opacity var(--dur-mid);
}
.lufs-reading.live::before { background: var(--c-green); opacity: 0.9; }

.lufs-reading-label {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  margin-bottom: 2px;
  letter-spacing: 0.04em;
}
.lufs-reading-value {
  font-size: var(--text-xl);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--c-text-1);
  transition: color var(--dur-mid);
}
.lufs-reading-value.warn { color: var(--c-orange); }
.lufs-reading-value.over { color: var(--c-primary); text-shadow: 0 0 12px var(--c-primary-glow); }

/* ── Transport ──────────────────────────────────────────── */
.transport {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: var(--sp-4);
  padding: 0 var(--sp-5);
  background: var(--c-bg-surface);
  border-top: 1px solid var(--c-border);
}

.transport-time {
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--c-text-1);
  min-width: 120px;
}

.transport-time .time-total { color: var(--c-text-3); font-size: var(--text-md); }

.transport-controls { display: flex; align-items: center; gap: var(--sp-2); }

.transport-btn {
  width: 36px;
  height: 36px;
  border-radius: var(--r-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--c-text-2);
  border: 1px solid var(--c-border);
  transition: all var(--dur-fast);
  font-size: 13px;
}

.transport-btn:hover { background: var(--c-bg-elevated); color: var(--c-text-1); border-color: var(--c-border-hover); }
.transport-btn:active { transform: scale(0.94); }

.transport-btn.play-btn {
  width: 44px;
  height: 44px;
  background: var(--c-primary);
  border-color: var(--c-primary);
  color: #fff;
  font-size: 15px;
  box-shadow: 0 0 16px var(--c-primary-glow);
}

.transport-btn.play-btn:hover {
  background: var(--c-primary-h);
  border-color: var(--c-primary-h);
  box-shadow: 0 0 24px var(--c-primary-glow);
}
.transport-btn.active { background: var(--c-bg-elevated); color: var(--c-primary); border-color: var(--c-primary); }

.transport-progress {
  flex: 1;
  height: 5px;
  background: var(--c-bg-overlay);
  border-radius: 3px;
  position: relative;
  cursor: pointer;
  transition: height var(--dur-fast);
  /* Expand the hit area well beyond the visual bar (Fitts) */
  background-clip: content-box;
  padding: 10px 0;
  box-sizing: content-box;
}

.transport-progress:hover { height: 8px; }

.transport-progress-fill {
  position: absolute;
  top: 10px; bottom: 10px; left: 0;
  height: auto;
  background: linear-gradient(90deg, var(--c-primary), var(--c-primary-h));
  border-radius: 3px;
  transition: width 0.05s linear;
  pointer-events: none;
}

/* Seek thumb appears on hover at the playhead position */
.transport-progress-fill::after {
  content: '';
  position: absolute;
  right: -6px;
  top: 50%;
  transform: translateY(-50%) scale(0);
  width: 12px;
  height: 12px;
  background: #fff;
  border-radius: 50%;
  box-shadow: 0 0 8px var(--c-primary-glow);
  transition: transform var(--dur-fast) var(--ease-out);
}
.transport-progress:hover .transport-progress-fill::after { transform: translateY(-50%) scale(1); }

.transport-right {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-left: auto;
}

.vol-knob-wrap { display: flex; align-items: center; gap: var(--sp-2); font-size: var(--text-xs); color: var(--c-text-3); }

/* ── Processing overlay ─────────────────────────────────── */
#processing-overlay {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--sp-6);
  background: rgba(10,10,15,0.9);
  backdrop-filter: blur(8px);
}

#processing-overlay.visible { display: flex; }

.processing-wave {
  display: flex;
  align-items: flex-end;
  gap: 4px;
  height: 40px;
}

.processing-wave-bar {
  width: 4px;
  background: var(--c-primary);
  border-radius: 2px;
  animation: wave-bar 1s ease-in-out infinite;
}

.processing-wave-bar:nth-child(1) { animation-delay: 0s;    height: 20%; }
.processing-wave-bar:nth-child(2) { animation-delay: 0.1s;  height: 40%; }
.processing-wave-bar:nth-child(3) { animation-delay: 0.2s;  height: 80%; }
.processing-wave-bar:nth-child(4) { animation-delay: 0.3s;  height: 100%; }
.processing-wave-bar:nth-child(5) { animation-delay: 0.4s;  height: 80%; }
.processing-wave-bar:nth-child(6) { animation-delay: 0.5s;  height: 40%; }
.processing-wave-bar:nth-child(7) { animation-delay: 0.6s;  height: 20%; }
.processing-wave-bar:nth-child(8) { animation-delay: 0.5s;  height: 40%; }
.processing-wave-bar:nth-child(9) { animation-delay: 0.4s;  height: 60%; }
.processing-wave-bar:nth-child(10){ animation-delay: 0.3s;  height: 90%; }
.processing-wave-bar:nth-child(11){ animation-delay: 0.2s;  height: 60%; }
.processing-wave-bar:nth-child(12){ animation-delay: 0.1s;  height: 30%; }

.processing-step { font-size: var(--text-md); color: var(--c-text-2); }
.processing-step strong { color: var(--c-text-1); }

.processing-progress-bar {
  width: 280px;
  height: 3px;
  background: var(--c-bg-overlay);
  border-radius: 2px;
  overflow: hidden;
}

.processing-progress-fill {
  height: 100%;
  background: var(--c-primary);
  border-radius: 2px;
  transition: width 0.3s var(--ease-out);
}

/* ── Knob component ─────────────────────────────────────── */
.knob-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  cursor: ns-resize;
  user-select: none;
}

.knob-svg { overflow: visible; }

.knob-label { font-size: 9px; color: var(--c-text-3); text-transform: uppercase; letter-spacing: 0.06em; text-align: center; }
.knob-value { font-size: 10px; font-family: var(--font-mono); color: var(--c-text-2); text-align: center; }

/* ── EQ module ──────────────────────────────────────────── */
.eq-canvas-wrap {
  width: 100%;
  height: 120px;
  background: var(--c-bg-input);
  border-radius: var(--r-sm);
  overflow: hidden;
  margin-bottom: var(--sp-3);
  cursor: crosshair;
  position: relative;
}

#eq-canvas { width: 100%; height: 100%; }

.eq-bands {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: var(--sp-2);
}

.eq-band {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.eq-linphase-row {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  margin: var(--sp-3) 0;
  font-size: var(--text-xs);
  color: var(--c-text-2);
  cursor: pointer;
}
.eq-linphase-row input { accent-color: var(--c-primary); cursor: pointer; }

.eq-match-row {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-bottom: var(--sp-3);
}
.eq-match-btn {
  flex-shrink: 0;
  padding: 5px var(--sp-3);
  background: var(--c-bg-overlay);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--c-text-2);
  cursor: pointer;
  transition: border-color var(--dur-fast), color var(--dur-fast);
}
.eq-match-btn:hover { border-color: var(--c-primary); color: var(--c-text-1); }
.eq-match-status {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.eq-match-status.err { color: var(--c-primary-h); }

/* ── Spectrum canvas ─────────────────────────────────────── */
.spectrum-wrap {
  width: 100%;
  height: 60px;
  background: var(--c-bg-input);
  border-radius: var(--r-sm);
  overflow: hidden;
  margin-top: var(--sp-3);
}

#spectrum-canvas { width: 100%; height: 100%; }

.spectrogram-wrap {
  width: 100%;
  height: 96px;
  background: #04040E;
  border-radius: var(--r-sm);
  overflow: hidden;
  margin-top: var(--sp-2);
}
#spectrogram-canvas { display: block; width: 100%; height: 100%; }

/* ── Compressor module ──────────────────────────────────── */
.comp-controls { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--sp-3); }

/* Multiband: crossover row + per-band rows */
.mbc-xovers {
  display: flex;
  justify-content: space-around;
  gap: var(--sp-3);
  margin: var(--sp-3) 0;
  padding-bottom: var(--sp-3);
  border-bottom: 1px solid var(--c-border);
}
.mbc-band {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-bottom: var(--sp-2);
}
.mbc-band-label {
  width: 40px;
  flex-shrink: 0;
  font-size: var(--text-xs);
  font-weight: 700;
  color: var(--c-text-2);
  letter-spacing: 0.04em;
}
.mbc-band .knob-wrap { flex: 1; }
.comp-controls { margin-top: var(--sp-3); padding-top: var(--sp-3); border-top: 1px solid var(--c-border); }

.comp-gr-canvas {
  width: 100%;
  height: 80px;
  background: var(--c-bg-input);
  border-radius: var(--r-sm);
  margin-bottom: var(--sp-3);
}

.comp-gr-label {
  font-size: var(--text-xs);
  color: var(--c-text-3);
  text-align: center;
  margin-top: 4px;
  font-family: var(--font-mono);
}

/* GR meter for De-esser / Dynamic EQ — fills downward as reduction increases */
.gr-meter {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  margin-top: var(--sp-3);
}
.gr-meter-bar {
  flex: 1;
  height: 6px;
  background: var(--c-bg-input);
  border-radius: 3px;
  overflow: hidden;
}
.gr-meter-fill {
  height: 100%;
  width: 0%;
  background: var(--c-green);
  border-radius: 3px;
  transition: width 0.1s linear, background 0.1s linear;
}
.gr-meter-fill.active { background: var(--c-orange); }
.gr-meter-fill.heavy  { background: var(--c-primary); }
.gr-meter-label {
  font-size: var(--text-xs);
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  color: var(--c-text-3);
  min-width: 72px;
  text-align: right;
}

/* ── Vinyl module ───────────────────────────────────────── */
.vinyl-format-select {
  display: flex;
  gap: var(--sp-2);
  margin-bottom: var(--sp-3);
}

.vinyl-format-btn {
  flex: 1;
  padding: var(--sp-2);
  background: var(--c-bg-overlay);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--c-text-3);
  text-align: center;
  cursor: pointer;
  transition: all var(--dur-fast);
}

.vinyl-format-btn.active { border-color: var(--c-primary); color: var(--c-primary); background: var(--c-primary-muted); }

.vinyl-warnings { display: flex; flex-direction: column; gap: var(--sp-2); }

.vinyl-warning {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  font-size: var(--text-xs);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-sm);
  background: var(--c-bg-overlay);
}

.vinyl-warning.ok    { color: var(--c-green); }
.vinyl-warning.warn  { color: var(--c-orange); background: rgba(255,165,2,0.08); }
.vinyl-warning.error { color: var(--c-primary); background: var(--c-primary-dim); }

.vinyl-time-bar-wrap {
  height: 8px;
  background: var(--c-bg-overlay);
  border-radius: 4px;
  overflow: hidden;
  margin: var(--sp-2) 0;
}

.vinyl-time-bar { height: 100%; border-radius: 4px; transition: width 0.3s, background 0.3s; }

/* ── Animations ─────────────────────────────────────────── */
@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-8px); }
  75% { transform: translateX(8px); }
}

@keyframes wave-bar {
  0%, 100% { transform: scaleY(0.3); }
  50% { transform: scaleY(1); }
}

@keyframes flash-value {
  0%   { background: var(--c-primary-muted); border-radius: var(--r-sm); }
  60%  { background: var(--c-primary-muted); }
  100% { background: transparent; }
}

@keyframes waveform-idle-scan {
  0%   { left: -100%; }
  100% { left: 120%; }
}

/* ── Tooltips ───────────────────────────────────────────── */
[data-tooltip] { position: relative; }
[data-tooltip]::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%) translateY(2px);
  padding: 4px 8px;
  background: var(--c-bg-overlay);
  border: 1px solid var(--c-border);
  border-radius: var(--r-sm);
  font-size: var(--text-xs);
  color: var(--c-text-1);
  white-space: nowrap;
  pointer-events: none;
  z-index: 50;
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--dur-fast) var(--ease-out) 300ms,
              transform var(--dur-fast) var(--ease-out) 300ms,
              visibility 0s 300ms;
}
[data-tooltip]:hover::after {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

/* ── Responsive (RWD) ───────────────────────────────────── */
@media (max-width: 900px) {
  :root { --chain-w: 280px; }
  .waveform-zoom-label { display: none; }
  .meters-panel {
    grid-template-columns: 1fr;
    grid-template-areas:
      "title"
      "readings"
      "corr"
      "gonio"
      "graph"
      "platforms";
  }
  .gonio-wrap { aspect-ratio: 16 / 10; }
}

@media (max-width: 680px) {
  /* Mobile: natural page flow + body scroll instead of fixed 100dvh grid —
     the fixed grid squeezed the waveform to ~0px and clipped the chain panel */
  html, body { max-width: 100%; overflow-x: hidden; }
  body { overflow-y: auto; }

  #app {
    grid-template-columns: 1fr;
    grid-template-rows: auto auto auto auto auto;
    height: auto;
    min-height: 100dvh;
    min-width: 0;
    max-width: 100vw;
    overflow: visible;
  }

  .main-waveform-panel { min-height: 220px; }
  .waveform-toolbar { flex-wrap: wrap; }
  .waveform-zoom { width: 100%; margin-left: 0; justify-content: flex-end; }
  .waveform-zoom-label { display: inline; margin-right: auto; }

  .chain-panel {
    grid-column: 1;
    grid-row: 4;
    border-left: none;
    border-top: 1px solid var(--c-border);
    height: auto;
    overflow: visible;
  }

  .chain-modules,
  .meters-panel {
    flex: none;
    min-height: 0;
    overflow: visible;
  }

  .meters-panel {
    grid-template-columns: minmax(120px, 0.8fr) minmax(0, 1.2fr);
    grid-template-areas:
      "title title"
      "readings readings"
      "corr corr"
      "gonio graph"
      "gonio platforms";
  }

  .workspace { grid-column: 1; grid-row: 3; }

  :root { --stems-h: 150px; }

  .header {
    width: 100%;
    min-width: 0;
    max-width: 100vw;
    flex-wrap: wrap;
    gap: var(--sp-2);
    padding: var(--sp-2) var(--sp-3);
    overflow: hidden;
  }
  .header .upload-zone { min-width: 160px; }
  .header-actions {
    flex: 1 0 100%;
    min-width: 0;
    max-width: 100%;
    margin-left: 0;
    overflow-x: auto;
    overflow-y: hidden;
    contain: inline-size;
    scrollbar-width: none;
  }
  .header-actions::-webkit-scrollbar { display: none; }
  .upload-formats { display: none; }
  .ab-btn { padding: 5px 10px; }

  /* Pills must scroll, not silently clip (base rule is overflow: hidden) */
  .analysis-bar {
    width: 100%;
    min-width: 0;
    max-width: 100vw;
    flex-wrap: wrap;
    gap: var(--sp-2);
    padding: var(--sp-2) var(--sp-3);
    overflow: visible;
  }
  .analysis-sep { display: none; }
  .analysis-pill { flex: 1 1 auto; justify-content: center; }
  .analysis-status { flex: 1 0 100%; margin-left: 0; justify-content: flex-end; }

  .album-panel {
    height: auto;
    min-height: var(--stems-h);
    overflow: visible;
  }
  .album-head { flex-wrap: wrap; align-items: center; }
  .album-title-label { flex: 1 1 auto; }
  .album-target { order: 3; }
  #album-align-btn,
  #album-export-btn { order: 4; flex: 1 1 120px; }
  .album-cols { display: none; }
  .album-row {
    grid-template-columns: 28px minmax(0, 1fr) auto;
    grid-template-areas:
      "num title ops"
      ". lufs ops"
      ". gain ops"
      ". gap ops"
      ". isrc ops";
    gap: var(--sp-2);
    padding: var(--sp-3);
  }
  .album-row .ac-num { grid-area: num; }
  .album-row .ac-title { grid-area: title; }
  .album-row .ac-lufs { grid-area: lufs; }
  .album-row .ac-gain { grid-area: gain; }
  .album-row .ac-gap { grid-area: gap; }
  .album-row .ac-isrc { grid-area: isrc; }
  .album-row .ac-ops {
    grid-area: ops;
    flex-direction: column;
    align-self: stretch;
    justify-content: center;
  }
  .album-row .ac-gain::before { content: '增益 '; color: var(--c-text-3); }
  .album-row .ac-gap::before { content: '間隙 '; color: var(--c-text-3); }
  .album-row .ac-isrc::before { content: 'ISRC '; color: var(--c-text-3); font-size: var(--text-xs); }
  .album-op-btn { width: 32px; height: 32px; }

  /* Keep transport in document flow so it never covers lower parameters. */
  .transport {
    grid-row: 5;
    position: relative;
    z-index: 1;
    flex-wrap: wrap;
    height: auto;
    row-gap: 0;
    padding: var(--sp-2) var(--sp-3);
    box-shadow: 0 -4px 16px rgba(0,0,0,0.35);
  }
  .transport-progress { flex-basis: 100%; order: -1; }
  .transport-time { min-width: 0; }
}