* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary: #9333ea;
  --primary-dark: #7e22ce;
  --secondary: #d946ef;
  --accent: #c084fc;
  --bg: #0c0618;
  --bg-light: #1a0f2e;
  --bg-card: #160d24;
  --text: #f1f5f9;
  --text-muted: #94a3b8;
  --border: #334155;
  --white-key: #f8fafc;
  --black-key: #1e293b;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
}

body {
  font-family: 'Inter', 'Noto Sans', 'Segoe UI', system-ui, -apple-system, sans-serif;
  background: var(--bg);
  background-image: radial-gradient(ellipse at 50% -20%, rgba(147, 51, 234, 0.18), transparent 50%);
  color: var(--text);
  min-height: 100vh;
  line-height: 1.6;
}

.app-header {
  background: #efe6ff;
  padding: 1.25rem 1rem 1.5rem;
  border-bottom: 1px solid rgba(147, 51, 234, 0.18);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1100px;
  margin: 0 auto 0.5rem;
  gap: 1rem;
}

.logo-boz {
  flex-shrink: 0;
  line-height: 0;
  background: transparent;
}

.logo-img {
  display: block;
  height: clamp(44px, 11vw, 68px);
  width: auto;
  max-width: min(260px, 58vw);
  object-fit: contain;
  background: transparent;
  filter: none;
  user-select: none;
  -webkit-user-drag: none;
}

.lang-select-wrap {
  flex-shrink: 0;
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  flex-shrink: 0;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.lang-select {
  background: var(--bg);
  border: 1px solid rgba(147, 51, 234, 0.5);
  color: var(--text);
  padding: 0.45rem 0.75rem;
  border-radius: 8px;
  font-size: 0.9rem;
  cursor: pointer;
}

.lang-select:hover,
.lang-select:focus {
  border-color: var(--primary);
  outline: none;
}

.midi-wrap {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  flex-shrink: 0;
  flex-wrap: wrap;
  justify-content: flex-end;
  max-width: min(100%, 320px);
}

.midi-btn {
  background: var(--bg);
  border: 1px solid rgba(147, 51, 234, 0.5);
  color: var(--text);
  padding: 0.45rem 0.7rem;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
}

.midi-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: rgba(147, 51, 234, 0.15);
}

.midi-btn.active {
  border-color: var(--success);
  background: rgba(16, 185, 129, 0.12);
}

.midi-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.midi-select {
  background: var(--bg);
  border: 1px solid rgba(147, 51, 234, 0.45);
  color: var(--text);
  padding: 0.35rem 0.5rem;
  border-radius: 8px;
  font-size: 0.8rem;
  max-width: 140px;
}

.midi-status {
  font-size: 0.75rem;
  color: var(--text-muted);
  max-width: 120px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.midi-status.midi-ok {
  color: var(--success);
}

.midi-status.midi-err {
  color: var(--danger);
}

@media (max-width: 720px) {
  .header-bar {
    flex-wrap: wrap;
    justify-content: center;
  }

  .midi-wrap {
    width: 100%;
    justify-content: center;
    max-width: none;
  }

  .midi-status {
    max-width: none;
    flex: 1 1 100%;
    text-align: center;
  }
}

.subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 1rem;
  font-size: 0.95rem;
}

.nav-tabs {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  max-width: 100%;
  padding: 0 0.5rem;
}

.tab-btn {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.6rem 1.2rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.95rem;
  transition: all 0.2s;
  white-space: nowrap;
  flex-shrink: 0;
}

.tab-btn:hover {
  background: var(--bg-light);
  border-color: var(--primary);
}

.tab-btn.active {
  background: var(--primary);
  border-color: var(--primary);
}

.tab-panel {
  display: none;
  padding: 2rem 1rem;
  max-width: 1400px;
  margin: 0 auto;
}

.tab-panel.active {
  display: block;
}

h2 {
  margin-bottom: 1.5rem;
  color: var(--text);
}

/* Diatonic-inspired theme for non-guitar tabs */
#piano,
#scales,
#chords,
#sheetmusic,
#composer,
#metronome,
#tuner {
  --warm-ink: #15110d;
  --warm-panel: #241b13;
  --warm-panel-alt: #2a2016;
  --warm-brass: #e8a33d;
  --warm-brass-strong: #d98f2a;
  --warm-cream: #efe7d8;
  --warm-muted: #a48f74;
  --warm-line: #3a2c1f;
  --warm-neck-top: #3a2718;
  --warm-neck-bottom: #2c1d12;
  --warm-paper: #fbf6ec;
  --warm-paper-line: #d6c6aa;
}

#piano h2,
#scales h2,
#chords h2,
#sheetmusic h2,
#composer h2,
#metronome h2,
#tuner h2 {
  color: var(--warm-cream);
  font-weight: 800;
  letter-spacing: -0.02em;
}

#piano .piano-container,
#scales .scales-controls,
#scales .scale-display,
#chords .scales-controls,
#chords .scale-display,
#sheetmusic .training-controls,
#sheetmusic .sheetmusic-controls,
#sheetmusic #trainingEarPanel,
#composer .composer-main,
#composer .tracks-panel,
#metronome .metronome-container,
#tuner .tuner-container {
  background: radial-gradient(120% 80% at 50% -10%, #2a2017 0%, var(--warm-ink) 60%), var(--warm-ink);
  color: var(--warm-cream);
  border: 1px solid var(--warm-line);
  border-radius: 16px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04), 0 18px 40px -28px rgba(0, 0, 0, 0.7);
}

#piano .piano-container,
#composer .composer-main {
  padding: 1.5rem;
}

#sheetmusic #trainingEarPanel {
  max-width: 800px;
  margin: 0 auto;
  padding: 1.25rem 1.5rem 1.5rem;
}

#piano .piano-info,
#scales .scale-description,
#chords .scale-description,
#sheetmusic .quiz-score,
#sheetmusic .ear-feedback,
#composer .comp-hint,
#metronome .tempo-name,
#tuner .scale-description,
#tuner .tuner-target,
#tuner .tuner-detected-freq,
#tuner .tuner-status,
#tuner .tuner-mic-status,
#tuner .tuner-string-freq,
#tuner .tuner-auto-label,
#metronome .bpm-unit {
  color: var(--warm-muted);
}

#piano .current-note,
#scales .scale-title,
#chords .scale-title,
#metronome .bpm-value,
#tuner .tuner-note,
#composer .composer-panel-title {
  background: linear-gradient(90deg, #f0ab44, var(--warm-brass-strong));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

#scales .control-group label,
#chords .control-group label,
#sheetmusic .control-group label,
#metronome .control-group label,
#tuner .control-group label,
#composer .tracks-header,
#composer .composer-settings-title,
#composer .track-count,
#composer .track-vol-label,
#composer .track-eq-title,
#composer .fx-slider,
#composer .comp-inline-label {
  color: var(--warm-muted);
}

#scales .control-group select,
#chords .control-group select,
#sheetmusic .control-group select,
#metronome .control-group select,
#tuner .control-group select,
#composer .comp-name-input,
#composer .composer-save select,
#composer .track-row select,
#composer .comp-inline-label select,
#composer .comp-toggle {
  background: var(--warm-panel);
  color: var(--warm-cream);
  border: 1px solid var(--warm-line);
  border-radius: 10px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

#piano .play-btn,
#scales .play-btn,
#chords .play-btn,
#sheetmusic .play-btn,
#sheetmusic .reset-btn,
#sheetmusic .ear-btn,
#composer .play-btn,
#composer .reset-btn,
#composer .comp-import-label,
#metronome .play-btn,
#metronome .tempo-btn,
#tuner .play-btn {
  background: linear-gradient(180deg, #f0ab44, #d6892a);
  color: #1c1409;
  border: 1px solid rgba(240, 171, 68, 0.7);
  border-radius: 11px;
  box-shadow: 0 4px 16px -6px rgba(232, 163, 61, 0.65);
}

#piano .play-btn:hover,
#scales .play-btn:hover,
#chords .play-btn:hover,
#sheetmusic .play-btn:hover,
#sheetmusic .reset-btn:hover,
#sheetmusic .ear-btn:hover,
#composer .play-btn:hover,
#composer .reset-btn:hover,
#composer .comp-import-label:hover,
#metronome .play-btn:hover,
#metronome .tempo-btn:hover,
#tuner .play-btn:hover {
  background: linear-gradient(180deg, #f6b95d, #dd9530);
  border-color: #f6b95d;
}

#sheetmusic .sheet-letter-btn {
  border-color: var(--warm-paper-line);
  background: linear-gradient(180deg, #fffdf8, #f5efe4);
  color: #2a2017;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.18);
}

#sheetmusic .sheet-letter-btn:hover:not(:disabled) {
  border-color: var(--warm-brass);
  background: linear-gradient(180deg, #fffaf0, #f3e2bf);
  box-shadow: 0 6px 18px rgba(232, 163, 61, 0.28);
}

#sheetmusic .sheet-letter-btn.highlight {
  border-color: var(--warm-brass);
  background: #fef3c7;
  box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.35);
}

#sheetmusic .sheet-letter-btn.correct,
#sheetmusic .ear-btn.correct {
  border-color: var(--success);
  background: #d1fae5;
  color: #065f46;
}

#sheetmusic .sheet-letter-btn.wrong,
#sheetmusic .ear-btn.wrong {
  border-color: var(--danger);
  background: #fee2e2;
  color: #991b1b;
}

#sheetmusic .staff-container,
#composer .staff-container {
  background: linear-gradient(180deg, #fffdf8, #f5efe4);
  border: 1px solid var(--warm-paper-line);
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.85), 0 18px 40px -28px rgba(0,0,0,0.55);
}

#sheetmusic .ear-btn,
#composer .track-row,
#composer .composer-mixer,
#composer .composer-settings-group,
#metronome .beat-dot,
#tuner .tuner-string-btn {
  border-color: var(--warm-line);
  background: rgba(36, 27, 19, 0.52);
}

#sheetmusic .ear-btn:hover,
#composer .track-row:hover,
#composer .track-row.active,
#metronome .tempo-btn:hover,
#tuner .tuner-string-btn:hover,
#tuner .tuner-string-btn.active {
  border-color: var(--warm-brass);
  box-shadow: 0 0 0 1px rgba(232, 163, 61, 0.22);
}

#composer .track-row.active {
  background: rgba(232, 163, 61, 0.14);
}

#metronome .beat-dot.lit {
  background: var(--warm-brass);
  border-color: var(--warm-brass);
  box-shadow: 0 0 16px rgba(232, 163, 61, 0.45);
}

#metronome .beat-dot.accent,
#metronome .beat-dot.accent.lit {
  border-color: #f6b95d;
}

#metronome .metro-start.running {
  background: var(--danger);
  border-color: var(--danger);
  color: white;
}

#metronome .metro-start.running:hover {
  background: #dc2626;
  border-color: #dc2626;
}

#metronome .bpm-slider,
#composer .bpm-slider,
#tuner input[type="range"] {
  accent-color: var(--warm-brass);
}

#tuner .tuner-gauge::after {
  background: var(--warm-panel);
  border-color: var(--warm-line);
}

#tuner .tuner-gauge-arc {
  border-color: var(--warm-line);
}

#tuner .tuner-needle {
  background: linear-gradient(to top, #a85d14, var(--warm-brass));
}

#tuner .tuner-gauge.in-tune .tuner-gauge-arc {
  border-color: #22c55e;
  box-shadow: 0 0 20px rgba(34, 197, 94, 0.35);
}

#tuner .tuner-gauge.sharp .tuner-gauge-arc {
  border-top-color: #f59e0b;
  border-right-color: #f59e0b;
}

#tuner .tuner-gauge.flat .tuner-gauge-arc {
  border-top-color: #3b82f6;
  border-left-color: #3b82f6;
}

#tuner .tuner-gauge.in-tune .tuner-needle {
  background: linear-gradient(to top, #16a34a, #22c55e);
}

#tuner .tuner-cents.is-sharp,
#tuner .tuner-status.is-sharp {
  color: #d97706;
}

#tuner .tuner-cents.is-flat,
#tuner .tuner-status.is-flat {
  color: #2563eb;
}

#tuner .tuner-cents.is-in-tune,
#tuner .tuner-status.is-in-tune,
#tuner .tuner-mic-status.tuner-ok {
  color: #16a34a;
}

#tuner .tuner-mic-status.tuner-err {
  color: #dc2626;
}

#tuner .tuner-string-btn.active {
  background: rgba(232, 163, 61, 0.12);
}

#tuner .tuner-string-btn.near {
  border-color: #22c55e;
  background: rgba(34, 197, 94, 0.08);
}

/* Piano Styles */
.piano-container {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 12px;
  border: 1px solid var(--border);
}

.piano-wrapper {
  overflow-x: auto;
  overflow-y: visible;
  padding: 1rem 0;
  display: flex;
  justify-content: center;
}

.piano-keyboard {
  display: flex;
  position: relative;
  height: 200px;
  user-select: none;
}

.key {
  cursor: pointer;
  border-radius: 0 0 6px 6px;
  transition: all 0.1s;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 8px;
  font-size: 0.75rem;
  font-weight: 600;
  min-width: 40px;
  flex: 0 0 auto;
}

.key.white {
  background: var(--white-key);
  border: 1px solid #cbd5e1;
  color: #475569;
  height: 200px;
  width: 50px;
  z-index: 1;
  padding: 10px 4px;
}

.key.white.mapped-range {
  background:
    linear-gradient(to top, rgba(99, 102, 241, 0.12), rgba(99, 102, 241, 0.12)) ,
    var(--white-key);
  border-color: rgba(99, 102, 241, 0.35);
  box-shadow: inset 0 -14px 0 rgba(99, 102, 241, 0.08);
}

.key.white:hover {
  background: #e2e8f0;
}

.key.white:active,
.key.white.active {
  background: var(--primary);
  color: white;
  transform: translateY(2px);
}

.key.black {
  background: var(--black-key);
  color: white;
  height: 130px;
  width: 34px;
  position: absolute;
  z-index: 2;
  padding: 8px 2px;
  border: 1px solid #0f172a;
}

.key.black.mapped-range {
  background: linear-gradient(to bottom, #475569, #1e293b);
  border-color: rgba(129, 140, 248, 0.55);
  box-shadow: 0 0 0 1px rgba(129, 140, 248, 0.18);
}

.key.black:hover {
  background: #334155;
}

.key.black:active,
.key.black.active {
  background: var(--secondary);
  border-color: var(--secondary);
}

.piano-info {
  margin-top: 1.5rem;
  text-align: center;
  color: var(--text-muted);
}

.current-note {
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

kbd {
  background: var(--bg);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
  border: 1px solid var(--border);
  font-family: monospace;
  font-size: 0.875rem;
}

/* Guitar Styles */
#guitar,
#guitarchords {
  --gtr-ink: #15110d;
  --gtr-panel: #241b13;
  --gtr-maple: #c9a876;
  --gtr-brass: #e8a33d;
  --gtr-cream: #efe7d8;
  --gtr-muted: #a48f74;
  --gtr-line: #3a2c1f;
  --gtr-neck-top: #3a2718;
  --gtr-neck-bottom: #2c1d12;
  --gtr-string: #caa06a;
  --gtr-wire: #8a7146;
  --gtr-hover: rgba(232, 163, 61, 0.22);
  --gtr-active: rgba(232, 163, 61, 0.45);
}

.guitar-container {
  background: radial-gradient(120% 80% at 50% -10%, #2a2017 0%, var(--gtr-ink) 60%), var(--gtr-ink);
  color: var(--gtr-cream);
  padding: 1.5rem;
  border-radius: 16px;
  border: 1px solid var(--gtr-line);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04), 0 18px 40px -28px rgba(0, 0, 0, 0.7);
}

.string-selector {
  margin-bottom: 1rem;
  color: var(--gtr-muted);
  font-weight: 600;
}

.string-selector select {
  background: var(--gtr-panel);
  color: var(--gtr-cream);
  border: 1px solid var(--gtr-line);
  padding: 0.6rem 1rem;
  border-radius: 10px;
  font-size: 0.95rem;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

.fretboard {
  overflow-x: auto;
  background: linear-gradient(180deg, var(--gtr-neck-top), var(--gtr-neck-bottom));
  border: 1px solid #4a3322;
  box-shadow: inset 0 1px 0 #5a3f28, 0 18px 40px -24px #000;
  padding: 1.2rem 1rem;
  border-radius: 14px;
  position: relative;
  min-height: 200px;
}

.fretboard-table {
  display: flex;
  flex-direction: column;
  gap: 6px;
  min-width: max-content;
}

.string-row {
  display: flex;
  align-items: center;
  gap: 0;
  position: relative;
  height: 34px;
}

.nut {
  width: 24px;
  min-width: 24px;
  height: 100%;
  background: linear-gradient(180deg, #efe7d8, #b8a073);
  border-radius: 3px 0 0 3px;
  z-index: 3;
  box-shadow: 0 0 4px rgba(0,0,0,0.3);
}

.fret-cell {
  position: relative;
  width: 56px;
  height: 100%;
  border-right: 2px solid #d9c39a;
  border-left: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s;
  border-radius: 0;
}

.fret-cell:hover {
  background: var(--gtr-hover);
}

.fret-cell.active {
  background: var(--gtr-active);
  box-shadow: inset 0 0 0 1px rgba(240, 171, 68, 0.55), 0 0 16px -8px var(--gtr-brass);
}

.fret-cell.blank {
  background: rgba(36, 27, 19, 0.28);
  cursor: default;
}

.fret-cell::before {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  background: var(--gtr-string);
  opacity: 0.72;
  transform: translateY(-50%);
  pointer-events: none;
}

.fret-marker {
  position: absolute;
  background: #5c4126;
  border-radius: 50%;
  pointer-events: none;
  opacity: 0.72;
}

.fret-number {
  position: absolute;
  right: 8px;
  top: 2px;
  font-size: 0.7rem;
  color: var(--gtr-muted);
  font-weight: bold;
}

.fret-label {
  font-size: 0.85rem;
  font-weight: 700;
  color: #1b1308;
  background: linear-gradient(180deg, #f6cd84, #e8a33d);
  min-width: 26px;
  height: 26px;
  border-radius: 999px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 6px -1px rgba(0,0,0,0.5);
  pointer-events: none;
  position: relative;
  z-index: 1;
}

.guitar-info {
  margin-top: 1rem;
  text-align: center;
  color: var(--gtr-muted);
}

#guitar .current-note,
#guitarchords .current-note {
  color: var(--gtr-brass);
}

/* Scales Styles */
.scales-controls {
  display: flex;
  gap: 1.5rem;
  align-items: flex-end;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.control-group label {
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 600;
}

.control-group select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 0.6rem 1rem;
  border-radius: 6px;
  font-size: 1rem;
  min-width: 180px;
}

.play-btn {
  background: var(--primary);
  color: white;
  border: none;
  padding: 0.6rem 1.5rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  transition: all 0.2s;
}

.play-btn:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

.scale-display {
  background: var(--bg-card);
  padding: 1.5rem;
  border-radius: 12px;
  border: 1px solid var(--border);
}

.piano-keys-mini {
  display: flex;
  justify-content: center;
  gap: 2px;
  margin-bottom: 1.5rem;
  min-height: 100px;
}

.scale-notes {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.scale-note-chip {
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  padding: 0.5rem 1.2rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 1.1rem;
}

.scale-note-chip.tonic {
  background: linear-gradient(135deg, var(--secondary), #be185d);
}

#chords .chord-tone-chip {
  color: #1b1308;
  box-shadow: 0 6px 18px -12px rgba(0, 0, 0, 0.45);
  transition: transform 0.15s, box-shadow 0.15s, filter 0.15s;
}

#chords .chord-tone-chip.degree-root {
  background: linear-gradient(135deg, #f6cd84, #e8a33d);
}

#chords .chord-tone-chip.degree-third {
  background: linear-gradient(135deg, #9fe0d4, #5cc0b0);
}

#chords .chord-tone-chip.degree-fifth {
  background: linear-gradient(135deg, #f3b29a, #e58062);
}

#chords .chord-tone-chip.degree-ext {
  background: linear-gradient(135deg, #eadcc6, #cfb692);
}

#chords .chord-tone-chip.active {
  transform: scale(1.1);
  box-shadow: 0 0 0 2px rgba(255, 248, 235, 0.55), 0 0 20px -6px rgba(232, 163, 61, 0.85);
  filter: brightness(1.06);
}

.intervals {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
}

.interval-badge {
  background: var(--bg);
  padding: 0.4rem 0.8rem;
  border-radius: 6px;
  font-size: 0.85rem;
  border: 1px solid var(--border);
}

.interval-badge.whole {
  border-left: 3px solid var(--success);
}

.interval-badge.half {
  border-left: 3px solid var(--danger);
}

/* Sheet Music Styles */
.training-controls {
  margin-bottom: 1rem;
}

.training-panel[hidden] {
  display: none !important;
}

.sheetmusic-controls {
  display: flex;
  gap: 1.5rem;
  align-items: flex-end;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.staff-container {
  background: white;
  border-radius: 12px;
  padding: 1.5rem;
  box-shadow: 0 4px 20px rgba(0,0,0,0.3);
  max-width: 800px;
  margin: 0 auto;
}

.quiz-answer {
  text-align: center;
  margin-top: 1.5rem;
  font-size: 1.5rem;
  font-weight: bold;
  color: var(--text-muted);
  min-height: 2rem;
}

.quiz-answer.correct {
  color: var(--success);
}

.quiz-answer.wrong {
  color: var(--danger);
}

.quiz-answer.revealed {
  color: var(--warning);
}

.quiz-score {
  text-align: center;
  margin-top: 1rem;
  font-size: 1.1rem;
}

.sheet-letter-pad {
  display: flex;
  justify-content: center;
  gap: 0.55rem;
  flex-wrap: wrap;
  margin-top: 1.25rem;
  padding-top: 0.25rem;
}

.sheet-letter-btn {
  min-width: 3.1rem;
  height: 3.1rem;
  padding: 0 0.75rem;
  font-size: 1.35rem;
  font-weight: 800;
  border-radius: 12px;
  border: 2px solid #cbd5e1;
  background: #f8fafc;
  color: #1e293b;
  cursor: pointer;
  transition: transform 0.12s, border-color 0.15s, background 0.15s, box-shadow 0.15s;
  font-family: Georgia, 'Times New Roman', serif;
}

.sheet-letter-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: #f3e8ff;
  transform: translateY(-2px);
  box-shadow: 0 4px 14px rgba(147, 51, 234, 0.25);
}

.sheet-letter-btn:active:not(:disabled) {
  transform: translateY(0);
}

.sheet-letter-btn:disabled {
  opacity: 0.55;
  cursor: default;
}

.sheet-letter-btn.highlight {
  border-color: var(--warning);
  background: #fef3c7;
  box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.35);
}

.sheet-letter-btn.correct {
  border-color: var(--success);
  background: #d1fae5;
  color: #065f46;
}

.sheet-letter-btn.wrong {
  border-color: var(--danger);
  background: #fee2e2;
  color: #991b1b;
}

.reset-btn {
  background: var(--danger);
  color: white;
  border: none;
  padding: 0.4rem 1rem;
  border-radius: 6px;
  cursor: pointer;
  margin-left: 0.5rem;
}

/* App layout with global settings panel */
.app-layout {
  display: flex;
  align-items: stretch;
  gap: 0;
}

.app-main {
  flex: 1;
  min-width: 0;
}

body:not([data-active-tab="composer"]) .settings-composer-only {
  display: none;
}

/* Composer */
.composer-page {
  display: flex;
  align-items: stretch;
  gap: 0;
  min-height: 420px;
}

.composer-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.composer-main-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem 1rem;
}

.composer-main-head h2 {
  margin: 0;
}

.composer-transport {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
}

.composer-mouse-tools {
  align-items: flex-end;
  margin: 0 0 0.6rem;
  padding: 0.8rem 0.95rem 0.35rem;
  border: 1px solid var(--warm-line);
  border-radius: 12px;
  background: rgba(36, 27, 19, 0.46);
}

.composer-mouse-tools .control-group {
  min-width: 8.5rem;
}

.comp-inline-number {
  width: 100%;
  min-height: 2.35rem;
  padding: 0.55rem 0.7rem;
  border-radius: 10px;
  border: 1px solid rgba(201, 168, 118, 0.38);
  background: rgba(20, 14, 10, 0.82);
  color: var(--text-primary);
  font: inherit;
}

.composer-notation-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
  align-items: flex-end;
}

.composer-notation-actions button {
  flex: 0 1 auto;
  min-width: 0;
  padding: 0.45rem 0.8rem;
  font-size: 0.92rem;
  line-height: 1.2;
}

.composer-settings {
  position: relative;
  flex-shrink: 0;
  width: var(--composer-settings-width, 300px);
  border-left: 1px solid var(--border);
  background: var(--bg-card);
  display: flex;
  transition: width 0.22s ease;
}

.composer-settings.resizing {
  transition: none;
}

.composer-settings.collapsed {
  width: 0;
  border-left: none;
  overflow: visible;
}

.composer-settings-resizer {
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 8px;
  transform: translateX(-50%);
  cursor: col-resize;
  z-index: 4;
  touch-action: none;
}

.composer-settings-resizer::after {
  content: '';
  position: absolute;
  left: 50%;
  top: 0;
  bottom: 0;
  width: 2px;
  transform: translateX(-50%);
  background: transparent;
  transition: background 0.15s;
}

.composer-settings-resizer:hover::after,
.composer-settings.resizing .composer-settings-resizer::after {
  background: var(--primary);
}

.composer-settings.collapsed .composer-settings-resizer {
  display: none;
}

body.composer-resizing {
  cursor: col-resize;
  user-select: none;
}

body.composer-resizing * {
  cursor: col-resize !important;
}

.composer-settings-tab {
  position: absolute;
  left: 0;
  top: 50%;
  transform: translate(-100%, -50%);
  z-index: 2;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  width: 44px;
  padding: 0.75rem 0.35rem;
  border: 1px solid var(--border);
  border-right: none;
  border-radius: 10px 0 0 10px;
  background: var(--bg-card);
  color: var(--text);
  cursor: pointer;
  font-size: 0.72rem;
  line-height: 1.2;
  transition: background 0.15s, border-color 0.15s;
}

.composer-settings-tab:hover {
  background: rgba(147, 51, 234, 0.12);
  border-color: var(--primary);
}

.composer-settings-tab-icon {
  font-size: 1.1rem;
}

.composer-settings-tab-label {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  transform: rotate(180deg);
  font-weight: 600;
  letter-spacing: 0.02em;
}

.composer-settings-inner {
  flex: 1;
  min-width: 0;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 0.75rem 0.85rem 1rem;
  max-height: calc(100vh - 140px);
}

.composer-settings.collapsed .composer-settings-inner {
  visibility: hidden;
  pointer-events: none;
}

.composer-settings-title {
  font-size: 0.95rem;
  margin: 0 0 0.65rem;
  color: var(--text-muted);
}

.composer-settings-group {
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 0.55rem;
  background: rgba(147, 51, 234, 0.04);
}

.composer-settings-group summary {
  cursor: pointer;
  padding: 0.5rem 0.65rem;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  list-style: none;
  user-select: none;
}

.composer-settings-group summary::-webkit-details-marker {
  display: none;
}

.composer-settings-group summary::before {
  content: '▸ ';
  color: var(--primary);
}

.composer-settings-group[open] summary::before {
  content: '▾ ';
}

.composer-settings-controls {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(108px, 1fr));
  gap: 0.45rem 0.55rem;
  padding: 0 0.65rem 0.65rem;
  margin-bottom: 0;
}

.composer-settings-controls .control-group {
  flex-direction: column;
  align-items: stretch;
  gap: 0.2rem;
  min-width: 0;
}

.composer-settings-controls .control-group label {
  font-size: 0.72rem;
  line-height: 1.2;
}

.composer-settings-controls .control-group select,
.composer-settings-controls .control-group .comp-toggle {
  width: 100%;
  box-sizing: border-box;
}

.composer-settings-controls .control-group-wide {
  grid-column: 1 / -1;
}

.composer-settings-controls .control-group-wide .bpm-slider {
  width: 100%;
}

.composer-key-octave-hint {
  grid-column: 1 / -1;
  font-size: 0.72rem;
  margin: 0;
  padding: 0 0.1rem;
}

.composer-settings-controls .comp-detected {
  font-size: 0.75rem;
  line-height: 1.35;
}

.composer-settings-block {
  padding: 0 0.65rem 0.65rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.composer-settings-btns {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.composer-settings-btns .play-btn {
  width: 100%;
  justify-content: center;
}

.composer-settings .composer-mixer {
  margin: 0;
  padding: 0 0.65rem 0.65rem;
  border: none;
  background: transparent;
}

.composer-settings .composer-fx-grid {
  grid-template-columns: 1fr;
}

.composer-settings .track-eq-grid {
  grid-template-columns: 1fr;
}

.composer-save-stack {
  flex-direction: column;
  align-items: stretch;
  margin-top: 0;
}

.composer-save-stack .comp-name-input,
.composer-save-stack select,
.composer-save-stack .play-btn,
.composer-save-stack .reset-btn,
.composer-save-stack .comp-import-label {
  width: 100%;
  margin-left: 0;
  justify-content: center;
}

.composer-actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 1rem;
}

.composer-staff-wrap {
  flex: 1;
  max-width: 100%;
  overflow-x: auto;
  min-height: 200px;
}

.composer-staff-wrap canvas {
  display: block;
}

.composer-save {
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  margin-top: 1.25rem;
}

.comp-name-input {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 0.55rem 0.9rem;
  border-radius: 6px;
  font-size: 0.95rem;
}

.composer-save select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 0.55rem 0.9rem;
  border-radius: 6px;
  font-size: 0.95rem;
  min-width: 160px;
}

.comp-import-label {
  display: inline-flex;
  align-items: center;
  cursor: pointer;
}

/* Compact composer controls */
.composer-compact.sheetmusic-controls {
  gap: 0.7rem 1rem;
  margin-bottom: 1rem;
}

.composer-compact .control-group label {
  font-size: 0.78rem;
}

.composer-compact select {
  min-width: unset;
  padding: 0.35rem 0.5rem;
  font-size: 0.88rem;
}

.composer-compact .bpm-slider {
  width: 130px;
}

.comp-toggle {
  padding: 0.35rem 0.9rem;
  font-size: 0.85rem;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text);
  cursor: pointer;
}

.comp-detected {
  font-size: 0.82rem;
  color: var(--secondary);
  font-weight: 600;
  white-space: nowrap;
}

.comp-hint kbd {
  font-size: 0.75rem;
  padding: 0.1rem 0.35rem;
}

/* Composer tracks panel */
.tracks-panel {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.6rem 0.8rem;
  margin-bottom: 0;
}

.tracks-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-bottom: 0.5rem;
  color: var(--text-muted);
  font-size: 0.82rem;
}

.tracks-header-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.comp-inline-label {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.comp-inline-label select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 0.3rem 0.45rem;
  border-radius: 6px;
  font-size: 0.82rem;
  max-width: 160px;
}

#compTracks {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.track-row {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.5rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.15s;
}

.track-row:hover { border-color: var(--primary); }

.track-row.active {
  border-color: var(--primary);
  background: rgba(147, 51, 234, 0.14);
}

.track-vol-wrap {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  min-width: 88px;
}

.track-vol {
  width: 56px;
  height: 4px;
  accent-color: var(--primary);
}

.track-vol-label {
  font-size: 0.72rem;
  color: var(--text-muted);
  min-width: 22px;
  text-align: right;
}

.composer-mixer {
  margin: 1rem 0;
  padding: 0.85rem 1rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: rgba(147, 51, 234, 0.06);
}

.composer-panel-title {
  font-size: 0.95rem;
  margin-bottom: 0.35rem;
}

.composer-mixer-hint {
  font-size: 0.82rem;
  margin-bottom: 0.75rem;
}

.composer-fx-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: 0.65rem 1rem;
}

.fx-slider {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.fx-slider strong {
  color: var(--accent);
  font-size: 0.8rem;
}

.fx-slider .bpm-slider {
  width: 100%;
}

.track-eq-panel {
  margin-top: 1rem;
  padding-top: 0.85rem;
  border-top: 1px solid var(--border);
}

.track-eq-title {
  font-size: 0.88rem;
  margin-bottom: 0.55rem;
  color: var(--text-muted);
}

.track-eq-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.65rem;
}

@media (max-width: 520px) {
  .track-eq-grid {
    grid-template-columns: 1fr;
  }
}

.track-name {
  font-weight: 700;
  font-size: 0.85rem;
}

.track-row select {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 0.25rem 0.4rem;
  border-radius: 6px;
  font-size: 0.82rem;
}

.track-count {
  color: var(--text-muted);
  font-size: 0.8rem;
  min-width: 18px;
  text-align: center;
}

.track-del {
  background: transparent;
  border: none;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--text-muted);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  line-height: 1;
}

.track-del:hover {
  color: #f87171;
  background: rgba(248, 113, 113, 0.12);
}

.comp-remove-track:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

@media (max-width: 860px) {
  .composer-page {
    flex-direction: column;
  }

  .composer-settings {
    width: 100%;
    border-left: none;
    border-top: 1px solid var(--border);
  }

  .composer-settings-resizer {
    display: none;
  }

  .composer-settings.collapsed {
    width: 100%;
  }

  .composer-settings-tab {
    position: static;
    transform: none;
    flex-direction: row;
    width: 100%;
    padding: 0.55rem 0.85rem;
    border: none;
    border-bottom: 1px solid var(--border);
    border-radius: 0;
  }

  .composer-settings-tab-label {
    writing-mode: horizontal-tb;
    transform: none;
  }

  .composer-settings-inner {
    max-height: 50vh;
  }
}

/* Ear Training Styles */
.ear-training-controls {
  display: flex;
  gap: 1.5rem;
  align-items: flex-end;
  margin-bottom: 2rem;
  flex-wrap: wrap;
}

.ear-answer-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
  margin-top: 1.5rem;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.ear-btn {
  background: var(--bg-card);
  border: 2px solid var(--border);
  color: var(--text);
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.2s;
  min-width: 100px;
}

.ear-btn:hover {
  border-color: var(--primary);
  background: var(--bg-light);
}

.ear-btn.correct {
  background: var(--success);
  border-color: var(--success);
  color: white;
}

.ear-btn.wrong {
  background: var(--danger);
  border-color: var(--danger);
  color: white;
}

.ear-feedback {
  text-align: center;
  margin-top: 1.5rem;
  font-size: 1.2rem;
  font-weight: 600;
  min-height: 2rem;
}

/* Extended Scale / Chord theory */
.scale-title {
  text-align: center;
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 0.25rem;
}

.scale-description {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.scale-degrees {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.degree-badge {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 0.35rem 0.75rem;
  border-radius: 6px;
  font-weight: 600;
  font-size: 0.9rem;
  min-width: 42px;
  text-align: center;
}

.interval-badge.aug {
  border-left: 3px solid var(--warning);
}

/* Full / Half step ruler */
.step-pattern-label {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-bottom: 0.25rem;
}

.step-pattern {
  text-align: center;
  font-family: monospace;
  font-size: 1.4rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--text);
  margin-bottom: 1rem;
}

.step-ruler-wrap {
  overflow-x: auto;
  padding: 0.5rem 0 1.5rem;
}

.step-ruler {
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: max-content;
  margin: 0 auto;
}

.ruler-note {
  display: flex;
  flex-direction: column;
  align-items: center;
  cursor: pointer;
  flex: 0 0 auto;
}

.ruler-dot {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary), var(--primary-dark));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.95rem;
  border: 3px solid transparent;
  transition: all 0.15s;
}

.ruler-note.tonic .ruler-dot {
  background: linear-gradient(135deg, var(--secondary), #be185d);
  border-color: #fff;
}

.ruler-dot.lit {
  transform: scale(1.18);
  box-shadow: 0 0 18px var(--primary);
}

.ruler-step {
  position: relative;
  flex: 0 0 auto;
  height: 6px;
  border-radius: 3px;
  margin: 0 -2px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.ruler-step.full {
  width: 76px;
  background: var(--success);
}

.ruler-step.half {
  width: 40px;
  background: var(--danger);
}

.ruler-step.aug {
  width: 90px;
  background: var(--warning);
}

.ruler-step-label {
  position: absolute;
  top: -22px;
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0 0.4rem;
}

.sub-heading {
  text-align: center;
  color: var(--text-muted);
  font-size: 1rem;
  margin: 1.5rem 0 1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.harmonized-chords {
  margin-top: 0.5rem;
}

.scale-examples {
  margin-top: 1.75rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
}

.scale-examples-list {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  margin-top: 0.75rem;
}

.scale-example-card {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.75rem 1rem;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 10px;
}

.scale-example-info {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 0;
}

.scale-example-info strong {
  font-size: 0.95rem;
  color: var(--text);
}

.scale-example-meta {
  font-size: 0.8rem;
  color: var(--text-muted, #94a3b8);
}

.scale-example-btns {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.scale-examples-empty {
  margin-top: 0.5rem;
  font-style: italic;
}

.chord-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

.chord-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.75rem 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  cursor: pointer;
  transition: all 0.15s;
  min-width: 70px;
}

.chord-card:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
}

.chord-card.active {
  background: var(--primary);
  border-color: var(--primary);
}

.chord-roman {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--secondary);
}

.chord-card.active .chord-roman {
  color: white;
}

.chord-name {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.chord-card.active .chord-name {
  color: white;
}

/* Guitar Chords */
.gc-card,
.gc-detail,
.gc-neck-wrap,
#guitarchords .scales-controls {
  color: var(--gtr-cream);
}

#guitarchords .scales-controls {
  background: radial-gradient(120% 80% at 50% -10%, #2a2017 0%, var(--gtr-ink) 60%), var(--gtr-ink);
  border: 1px solid var(--gtr-line);
  border-radius: 16px;
  padding: 1.25rem 1.1rem;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.04), 0 18px 40px -28px rgba(0,0,0,0.7);
}

#guitarchords .control-group label,
#guitarchords .gc-orientation-note,
#guitarchords .gc-info .scale-description,
#guitarchords .gc-neck-controls label {
  color: var(--gtr-muted);
}

#guitarchords .control-group select {
  background: var(--gtr-panel);
  color: var(--gtr-cream);
  border-color: var(--gtr-line);
  border-radius: 10px;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.04);
}

#guitarchords .toggle-group {
  border-color: var(--gtr-line);
}

#guitarchords .toggle-btn {
  background: var(--gtr-panel);
  color: var(--gtr-cream);
}

#guitarchords .toggle-btn:hover {
  background: #2e2317;
}

#guitarchords .toggle-btn.active {
  background: linear-gradient(180deg, #f0ab44, #d98f2a);
  color: #1c1409;
}

#guitarchords .play-btn {
  background: linear-gradient(180deg, #f0ab44, #d6892a);
  color: #1c1409;
}

#guitarchords .play-btn:hover {
  background: linear-gradient(180deg, #f6b95d, #dd9530);
}

.gc-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 2rem;
}

.gc-card {
  background: linear-gradient(180deg, #2a2016, #211912);
  border: 1px solid var(--gtr-line);
  border-radius: 14px;
  padding: 0.75rem;
  cursor: pointer;
  transition: transform 0.15s, border-color 0.15s, box-shadow 0.15s;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.03);
}

.gc-card:hover {
  border-color: var(--gtr-brass);
  box-shadow: 0 10px 26px -18px var(--gtr-brass);
  transform: translateY(-3px);
}

.gc-name {
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--gtr-cream);
}

.gc-diagram {
  display: block;
}

.gc-detail {
  background: radial-gradient(120% 80% at 50% -10%, #2a2017 0%, var(--gtr-ink) 60%), var(--gtr-ink);
  border: 1px solid var(--gtr-line);
  border-radius: 16px;
  padding: 2rem;
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
  align-items: center;
  justify-content: center;
}

.gc-info {
  flex: 1;
  min-width: 240px;
  max-width: 420px;
}

.gc-detail-title {
  font-size: 2rem;
  margin-bottom: 0.75rem;
  background: linear-gradient(90deg, #f0ab44, #d98f2a);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.gc-info .scale-description {
  text-align: left;
  line-height: 1.9;
}

.gc-btn-row {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.25rem;
  flex-wrap: wrap;
}

.toggle-group {
  display: flex;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  width: fit-content;
}

.toggle-btn {
  background: var(--bg);
  border: none;
  color: var(--text);
  padding: 0.6rem 1.4rem;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 600;
  transition: all 0.15s;
}

.toggle-btn:hover {
  background: var(--bg-light);
}

.toggle-btn.active {
  background: var(--primary);
  color: white;
}

.gc-orientation-note {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

.gc-section-title {
  text-align: center;
  margin: 2.5rem 0 0.5rem;
  color: var(--gtr-cream);
}

.gc-shape-buttons {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 1rem 0;
}

.gc-shape-btn {
  background: var(--bg-card);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.6rem 1rem;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.9rem;
  transition: all 0.15s;
}

.gc-shape-btn:hover {
  border-color: var(--primary);
}

.gc-shape-btn.active {
  background: var(--primary);
  border-color: var(--primary);
}

.gc-neck-controls {
  display: flex;
  align-items: center;
  gap: 1rem;
  justify-content: center;
  flex-wrap: wrap;
  margin: 1rem auto;
  max-width: 640px;
}

.gc-neck-controls .bpm-slider {
  flex: 1;
  min-width: 180px;
}

.gc-neck-name {
  text-align: center;
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0.5rem 0 1rem;
  color: var(--gtr-brass);
}

.gc-neck-wrap {
  overflow-x: auto;
  background: linear-gradient(180deg, var(--gtr-neck-top), var(--gtr-neck-bottom));
  border: 1px solid #4a3322;
  border-radius: 14px;
  padding: 1rem;
  box-shadow: inset 0 1px 0 #5a3f28, 0 18px 40px -24px #000;
}

.gc-neck-svg {
  display: block;
  margin: 0 auto;
}

.metro-start.active {
  background: var(--danger, #dc2626);
}

/* Tuner */
.tuner-container {
  background: var(--bg-card);
  padding: 1.5rem 2rem 2rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  max-width: 640px;
  margin: 0 auto;
}

.tuner-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  align-items: center;
  margin-bottom: 1.25rem;
}

.tuner-controls .control-group {
  flex: 1 1 14rem;
  min-width: 12rem;
}

.tuner-auto-label {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.9rem;
  cursor: pointer;
  user-select: none;
}

.tuner-display {
  text-align: center;
  margin-bottom: 1.25rem;
}

.tuner-target {
  font-size: 0.9rem;
  color: var(--text-muted, #64748b);
  margin: 0 0 0.5rem;
}

.tuner-note {
  font-size: 3.5rem;
  font-weight: 800;
  line-height: 1.1;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.tuner-detected-freq {
  font-size: 1rem;
  color: var(--text-muted, #64748b);
  margin-bottom: 0.75rem;
}

.tuner-gauge-wrap {
  max-width: 320px;
  margin: 0 auto;
}

.tuner-gauge {
  position: relative;
  height: 140px;
  margin-bottom: 0.35rem;
}

.tuner-gauge::after {
  content: '';
  position: absolute;
  left: 50%;
  bottom: 2px;
  width: 14px;
  height: 14px;
  margin-left: -7px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 3px solid var(--border);
  z-index: 3;
}

.tuner-gauge-arc {
  position: absolute;
  left: 50%;
  bottom: 8px;
  width: 220px;
  height: 110px;
  margin-left: -110px;
  border: 4px solid var(--border);
  border-bottom: none;
  border-radius: 220px 220px 0 0;
  box-sizing: border-box;
}

.tuner-gauge.in-tune .tuner-gauge-arc {
  border-color: #22c55e;
  box-shadow: 0 0 20px rgba(34, 197, 94, 0.35);
}

.tuner-gauge.sharp .tuner-gauge-arc {
  border-top-color: #f59e0b;
  border-right-color: #f59e0b;
}

.tuner-gauge.flat .tuner-gauge-arc {
  border-top-color: #3b82f6;
  border-left-color: #3b82f6;
}

.tuner-gauge-scale {
  position: absolute;
  left: 50%;
  bottom: 4px;
  width: 200px;
  margin-left: -100px;
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted, #64748b);
  padding: 0 0.25rem;
}

.tuner-needle {
  position: absolute;
  left: 50%;
  bottom: 8px;
  width: 4px;
  height: 100px;
  margin-left: -2px;
  transform-origin: bottom center;
  transform: rotate(0deg);
  transition: transform 0.08s ease-out;
  background: linear-gradient(to top, var(--primary), #ef4444);
  border-radius: 2px;
  z-index: 2;
}

.tuner-gauge.in-tune .tuner-needle {
  background: linear-gradient(to top, #16a34a, #22c55e);
}

.tuner-cents {
  font-size: 1.35rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--text, #0f172a);
}

.tuner-status {
  font-size: 0.95rem;
  margin-top: 0.25rem;
  min-height: 1.4em;
  color: var(--text-muted, #64748b);
}

.tuner-gauge.in-tune + .tuner-cents,
.tuner-gauge.in-tune ~ .tuner-status {
  color: #16a34a;
}

.tuner-cents.is-sharp,
.tuner-status.is-sharp {
  color: #d97706;
}

.tuner-cents.is-flat,
.tuner-status.is-flat {
  color: #2563eb;
}

.tuner-cents.is-in-tune,
.tuner-status.is-in-tune {
  color: #16a34a;
}

.tuner-strings {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1.25rem;
}

.tuner-string-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  min-width: 5.5rem;
  padding: 0.55rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg, #fff);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, box-shadow 0.15s;
  font: inherit;
}

.tuner-string-btn:hover {
  border-color: var(--primary);
}

.tuner-string-btn.active {
  border-color: var(--primary);
  background: rgba(99, 102, 241, 0.08);
  box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

.tuner-string-btn.near {
  border-color: #22c55e;
  background: rgba(34, 197, 94, 0.08);
}

.tuner-string-name {
  font-weight: 600;
  font-size: 0.85rem;
}

.tuner-string-freq {
  font-size: 0.72rem;
  color: var(--text-muted, #64748b);
}

.tuner-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  justify-content: center;
}

.tuner-actions .play-btn {
  min-width: 12rem;
}

.tuner-mic-status {
  text-align: center;
  font-size: 0.85rem;
  margin-top: 0.75rem;
  color: var(--text-muted, #64748b);
}

.tuner-mic-status.tuner-ok {
  color: #16a34a;
}

.tuner-mic-status.tuner-err {
  color: #dc2626;
}

#tunerPlayRef.active {
  opacity: 0.85;
}

@media (max-width: 480px) {
  .tuner-container {
    padding: 1.1rem 1rem 1.25rem;
  }

  .tuner-controls .control-group {
    min-width: 100%;
  }

  .tuner-gauge-wrap {
    max-width: 100%;
  }

  .tuner-gauge-arc {
    width: 192px;
    height: 96px;
    margin-left: -96px;
  }

  .tuner-gauge-scale {
    width: 176px;
    margin-left: -88px;
  }

  .tuner-needle {
    height: 88px;
  }

  .tuner-note {
    font-size: 2.75rem;
  }

  .tuner-string-btn {
    min-width: 4.75rem;
    padding: 0.45rem 0.5rem;
  }

  .tuner-actions .play-btn {
    width: 100%;
    min-width: 0;
  }
}

/* Metronome */
.metronome-container {
  background: var(--bg-card);
  padding: 2rem;
  border-radius: 12px;
  border: 1px solid var(--border);
  max-width: 600px;
  margin: 0 auto;
}

.metronome-display {
  text-align: center;
  margin-bottom: 1.5rem;
}

.bpm-value {
  font-size: 4rem;
  font-weight: 800;
  line-height: 1;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.bpm-unit {
  font-size: 1.2rem;
  margin-left: 0.5rem;
  color: var(--text-muted);
  -webkit-text-fill-color: var(--text-muted);
}

.tempo-name {
  color: var(--text-muted);
  font-style: italic;
  font-size: 1.1rem;
  margin-top: 0.25rem;
}

.beat-indicators {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  margin: 1.5rem 0;
  min-height: 28px;
}

.beat-dot {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--bg);
  border: 2px solid var(--border);
  transition: all 0.05s;
}

.beat-dot.accent {
  border-color: var(--secondary);
}

.beat-dot.lit {
  background: var(--primary);
  border-color: var(--primary);
  transform: scale(1.3);
  box-shadow: 0 0 16px var(--primary);
}

.beat-dot.accent.lit {
  background: var(--secondary);
  border-color: var(--secondary);
  box-shadow: 0 0 16px var(--secondary);
}

.metronome-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.bpm-slider {
  flex: 1;
  accent-color: var(--primary);
  cursor: pointer;
}

.tempo-btn {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.5rem 0.7rem;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 600;
  transition: all 0.15s;
  white-space: nowrap;
}

.tempo-btn:hover {
  border-color: var(--primary);
  background: var(--bg-light);
}

.metronome-options {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 1.5rem;
}

.metronome-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
}

.metro-start.running {
  background: var(--danger);
}

.metro-start.running:hover {
  background: #dc2626;
}

/* Larger labeled piano for the Chords tab */
.piano-keys-mini {
  position: relative;
  min-height: 150px;
  overflow-x: auto;
  overflow-y: visible;
  padding: 1rem 0.75rem 0.35rem;
  display: flex;
  justify-content: center;
  border-radius: 12px;
  background: linear-gradient(180deg, rgba(15, 23, 42, 0.05), rgba(15, 23, 42, 0.02));
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.55);
}

.piano-chord-key {
  border-radius: 0 0 6px 6px;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  padding-bottom: 8px;
  cursor: pointer;
  transition: all 0.12s;
  user-select: none;
  box-sizing: border-box;
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.12);
}

.piano-chord-key.white {
  background: linear-gradient(180deg, #fffdf9, #efe7d8);
  border: 1px solid #ccb690;
  color: #5a4631;
  z-index: 1;
  padding: 10px 4px;
}

.piano-chord-key.black {
  background: linear-gradient(180deg, #3b2b1f, #17110c);
  color: #f7eddc;
  z-index: 2;
  border: 1px solid #120d09;
  padding: 8px 2px;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.28);
}

.piano-chord-key.white:hover {
  background: linear-gradient(180deg, #fffdfc, #f4ead6);
}

.piano-chord-key.black:hover {
  background: linear-gradient(180deg, #4a3526, #211810);
}

.piano-chord-key.chord-member.white,
.piano-chord-key.chord-root.white {
  color: #1b1308;
}

.piano-chord-key.chord-member.black,
.piano-chord-key.chord-root.black {
  color: #1b1308;
}

.piano-chord-key.degree-root.white {
  background: linear-gradient(180deg, #f6cd84, #e8a33d);
  border-color: rgba(232, 163, 61, 0.55);
}

.piano-chord-key.degree-root.black {
  background: linear-gradient(180deg, #e8a33d, #b9801f);
  border-color: rgba(232, 163, 61, 0.75);
}

.piano-chord-key.degree-third.white {
  background: linear-gradient(180deg, #9fe0d4, #5cc0b0);
  border-color: rgba(92, 192, 176, 0.5);
}

.piano-chord-key.degree-third.black {
  background: linear-gradient(180deg, #5cc0b0, #3d9183);
  border-color: rgba(92, 192, 176, 0.7);
}

.piano-chord-key.degree-fifth.white {
  background: linear-gradient(180deg, #f3b29a, #e58062);
  border-color: rgba(229, 128, 98, 0.5);
}

.piano-chord-key.degree-fifth.black {
  background: linear-gradient(180deg, #e58062, #bd5640);
  border-color: rgba(229, 128, 98, 0.72);
}

.piano-chord-key.degree-ext.white {
  background: linear-gradient(180deg, #e9dcc6, #cfb692);
  border-color: rgba(201, 168, 118, 0.55);
  color: #1b1308;
}

.piano-chord-key.degree-ext.black {
  background: linear-gradient(180deg, #b99667, #80613d);
  border-color: rgba(201, 168, 118, 0.75);
  color: #1b1308;
}

.piano-chord-key.pressed {
  transform: translateY(2px);
  filter: brightness(1.08);
}

.pck-label {
  font-size: 0.8rem;
  font-weight: 700;
  pointer-events: none;
}

/* Solar System Mini Piano for Scales */
.solar-system-piano {
  position: relative;
  height: 60px;
  margin: 1.5rem 0;
  background: var(--bg);
  border-radius: 8px;
  padding: 10px 0;
}

.solar-key {
  position: absolute;
  top: 5px;
  height: 50px;
  border-radius: 4px;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 600;
  border: 2px solid transparent;
}

.solar-key.white {
  background: var(--white-key);
  color: #475569;
  width: 40px;
  border-color: #cbd5e1;
  border-radius: 0 0 6px 6px;
  box-shadow: 0 3px 8px rgba(15, 23, 42, 0.08);
}

.solar-key.black {
  background: linear-gradient(180deg, #1f2937, #020617);
  color: white;
  width: 26px;
  height: 35px;
  z-index: 2;
  border-color: #0f172a;
  border-radius: 0 0 5px 5px;
  box-shadow: 0 4px 10px rgba(2, 6, 23, 0.3);
}

.solar-key.white:hover {
  background: #e2e8f0;
}

.solar-key.black:hover {
  background: #334155;
}

.solar-key.active {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
  transform: translateY(2px);
}

.solar-key.black.active {
  background: linear-gradient(180deg, #f9a8d4, var(--secondary));
  border-color: var(--secondary);
}

/* Scrollbar styling for fretboard */
.fretboard::-webkit-scrollbar {
  height: 8px;
}

.fretboard::-webkit-scrollbar-track {
  background: var(--bg);
  border-radius: 4px;
}

.fretboard::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}

.fretboard::-webkit-scrollbar-thumb:hover {
  background: var(--primary);
}

/* Media Queries for Responsiveness */
@media (max-width: 768px) {
  .app-header h1 {
    font-size: 1.5rem;
  }

  .tab-btn {
    padding: 0.5rem 0.8rem;
    font-size: 0.85rem;
  }

  .tab-panel {
    padding: 1rem 0.5rem;
  }

  .piano-container,
  .guitar-container,
  .scale-display {
    padding: 1rem;
  }

  .piano-keyboard,
  .key.white {
    height: 150px;
  }

  .key.white {
    width: 36px;
    min-width: 36px;
    font-size: 0.65rem;
  }

  .key.black {
    height: 100px;
    width: 26px;
    font-size: 0.65rem;
  }

  .scales-controls,
  .sheetmusic-controls,
  .ear-training-controls {
    gap: 1rem;
    flex-direction: column;
    align-items: stretch;
  }

  .control-group select,
  .play-btn {
    width: 100%;
    min-width: unset;
  }

  .staff-container {
    padding: 0.5rem;
    overflow-x: auto;
  }

  #staffCanvas {
    width: 100%;
    height: auto;
    max-width: 100%;
  }

  .ear-answer-buttons {
    gap: 0.5rem;
  }

  .ear-btn {
    padding: 0.6rem 1rem;
    font-size: 0.9rem;
    min-width: 80px;
  }
}

@media (max-width: 480px) {
  .app-header h1 {
    font-size: 1.3rem;
  }

  .subtitle {
    font-size: 0.85rem;
  }

  .nav-tabs {
    gap: 0.3rem;
  }

  .tab-btn {
    padding: 0.4rem 0.6rem;
    font-size: 0.8rem;
    flex: 1 1 auto;
    min-width: 70px;
  }

  .piano-keyboard,
  .key.white {
    height: 120px;
  }

  .key.white {
    width: 28px;
    min-width: 28px;
    font-size: 0.6rem;
  }

  .key.black {
    height: 80px;
    width: 20px;
    font-size: 0.6rem;
  }

  .fret-cell {
    width: 40px;
  }

  .scale-notes {
    gap: 0.5rem;
  }

  .scale-note-chip {
    font-size: 0.95rem;
    padding: 0.4rem 0.9rem;
  }
}

@media (max-width: 360px) {
  .piano-keyboard,
  .key.white {
    height: 100px;
  }

  .key.white {
    width: 24px;
    min-width: 24px;
    font-size: 0.55rem;
  }

  .key.black {
    height: 65px;
    width: 17px;
  }

  .fret-cell {
    width: 34px;
  }
}