* {
  box-sizing: border-box;
}

:root {
  --bg: #f4efe7;
  --card: rgba(255, 255, 255, 0.84);
  --card-solid: #ffffff;
  --ink: #171717;
  --muted: #6b665f;
  --border: #ddd4c7;
  --accent: #d97706;
  --accent-2: #f59e0b;
  --soft: rgba(245, 158, 11, 0.13);
  --f1: #2563eb;
  --f2: #16a34a;
  --f3: #ea580c;
  --f4: #9333ea;
  --mute: #ef4444;
  --open: #10b981;
  --shadow: 0 20px 50px rgba(42, 31, 16, 0.12);
  --radius: 24px;
}

body.dark {
  --bg: #0f172a;
  --card: rgba(15, 23, 42, 0.86);
  --card-solid: #111827;
  --ink: #f8fafc;
  --muted: #94a3b8;
  --border: #1f2937;
  --accent: #f59e0b;
  --accent-2: #fbbf24;
  --soft: rgba(251, 191, 36, 0.13);
  --shadow: 0 20px 60px rgba(0, 0, 0, 0.38);
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(245, 158, 11, 0.16), transparent 36rem),
    radial-gradient(circle at bottom right, rgba(217, 119, 6, 0.10), transparent 30rem),
    var(--bg);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.app-shell {
  max-width: 1280px;
  margin: 0 auto;
  padding: 24px;
}

.hero {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 18px;
  margin-bottom: 22px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-weight: 900;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

h1 {
  margin: 0;
  font-size: clamp(48px, 9vw, 98px);
  line-height: 0.86;
  letter-spacing: -0.08em;
}

.subtitle {
  margin: 18px 0 0;
  max-width: 820px;
  color: var(--muted);
  line-height: 1.55;
  font-size: 18px;
}

.theme-toggle,
button,
input,
select {
  font: inherit;
}

.theme-toggle {
  width: auto;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 12px 16px;
  background: var(--card);
  color: var(--ink);
  font-weight: 800;
  cursor: pointer;
  box-shadow: var(--shadow);
}

.controls,
.library-panel,
.teacher-panel,
.diagram-card,
.hand-card,
.info-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.controls {
  padding: 16px;
  display: grid;
  grid-template-columns: 1fr 220px 130px;
  gap: 12px;
  position: sticky;
  top: 12px;
  z-index: 5;
  margin-bottom: 18px;
}

input,
select {
  width: 100%;
  min-height: 50px;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 12px 14px;
  background: var(--card-solid);
  color: var(--ink);
  outline: none;
}

input:focus,
select:focus {
  border-color: rgba(245, 158, 11, 0.65);
  box-shadow: 0 0 0 4px rgba(245, 158, 11, 0.13);
}

.controls button,
.practice-button {
  border: none;
  min-height: 50px;
  border-radius: 16px;
  background: linear-gradient(180deg, var(--accent-2), var(--accent));
  color: #211100;
  font-weight: 900;
  cursor: pointer;
}

.layout {
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
}

.library-panel {
  padding: 16px;
  position: sticky;
  top: 98px;
  max-height: calc(100vh - 120px);
  overflow: hidden;
}

.panel-header,
.card-title,
.chord-header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
}

.panel-header {
  margin-bottom: 12px;
}

.panel-header span,
.card-title span,
.chord-category {
  color: var(--muted);
  font-size: 13px;
}

.chord-list {
  display: grid;
  gap: 8px;
  overflow: auto;
  max-height: calc(100vh - 172px);
  padding-right: 4px;
}

.chord-item {
  border: 1px solid var(--border);
  background: var(--card-solid);
  color: var(--ink);
  border-radius: 16px;
  padding: 12px;
  text-align: left;
  cursor: pointer;
}

.chord-item.active {
  border-color: rgba(245, 158, 11, 0.65);
  background: var(--soft);
}

.chord-item strong {
  display: block;
  font-size: 18px;
}

.chord-item span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  margin-top: 4px;
}

.teacher-panel {
  padding: 20px;
}

.chord-header {
  margin-bottom: 18px;
}

.chord-header h2 {
  margin: 0;
  font-size: clamp(34px, 6vw, 64px);
  letter-spacing: -0.06em;
  line-height: 0.95;
}

.chord-category {
  margin: 0 0 6px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 900;
}

#chordSummary {
  margin: 10px 0 0;
  color: var(--muted);
}

.practice-button.saved {
  background: #16a34a;
  color: white;
}

.visual-grid {
  display: grid;
  grid-template-columns: minmax(300px, 430px) minmax(280px, 1fr);
  gap: 16px;
  margin-bottom: 16px;
}

.diagram-card,
.hand-card,
.info-card {
  padding: 16px;
}

.chord-diagram {
  margin-top: 12px;
  display: grid;
  place-items: center;
}

.fretboard {
  width: min(100%, 360px);
  aspect-ratio: 0.78;
  position: relative;
}

.fretboard svg {
  width: 100%;
  height: 100%;
  display: block;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  margin-top: 12px;
  color: var(--muted);
  font-size: 13px;
}

.legend span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.legend i {
  width: 12px;
  height: 12px;
  border-radius: 999px;
  display: inline-block;
}

.finger-1 { background: var(--f1); }
.finger-2 { background: var(--f2); }
.finger-3 { background: var(--f3); }
.finger-4 { background: var(--f4); }

.hand-guide {
  margin-top: 12px;
  min-height: 360px;
  display: grid;
  place-items: center;
}

.hand-svg {
  width: min(100%, 360px);
  height: auto;
}

.explanation-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.info-card h3 {
  margin: 0 0 12px;
  font-size: 18px;
}

.info-card p {
  color: var(--muted);
  line-height: 1.55;
  margin: 0;
}

.guide-list {
  display: grid;
  gap: 10px;
}

.guide-row {
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 10px;
  align-items: start;
}

.guide-badge {
  width: 34px;
  height: 34px;
  border-radius: 999px;
  display: grid;
  place-items: center;
  color: white;
  font-weight: 900;
}

.guide-text strong {
  display: block;
}

.guide-text span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.4;
  margin-top: 3px;
}

ul {
  margin: 0;
  padding-left: 20px;
  color: var(--muted);
  line-height: 1.5;
}

.note-row,
.transition-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.note-pill,
.transition-pill {
  border-radius: 999px;
  padding: 8px 10px;
  background: var(--soft);
  color: var(--accent);
  font-weight: 900;
}

.transition-pill {
  border: none;
  cursor: pointer;
}

@media (max-width: 980px) {
  .layout,
  .visual-grid,
  .explanation-grid {
    grid-template-columns: 1fr;
  }

  .library-panel {
    position: static;
    max-height: none;
  }

  .chord-list {
    grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
    max-height: none;
  }
}

@media (max-width: 620px) {
  .app-shell {
    padding: 14px;
  }

  .hero {
    flex-direction: column;
  }

  .controls {
    grid-template-columns: 1fr;
    position: static;
  }

  .chord-header {
    flex-direction: column;
    align-items: stretch;
  }

  .teacher-panel,
  .library-panel,
  .diagram-card,
  .hand-card,
  .info-card {
    border-radius: 20px;
  }

  h1 {
    font-size: 48px;
  }
}


/* v2 learning features */

.chord-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
}

.secondary-button {
  border: 1px solid var(--border);
  min-height: 50px;
  border-radius: 16px;
  background: var(--card-solid);
  color: var(--ink);
  font-weight: 900;
  cursor: pointer;
  padding: 0 16px;
}

.secondary-button.active {
  background: #2563eb;
  color: white;
  border-color: transparent;
}

.learning-lab {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 16px;
}

.practice-lab,
.progression-list,
.lesson-path {
  display: grid;
  gap: 10px;
}

.practice-lab select,
.scale-controls select {
  min-height: 44px;
  border-radius: 14px;
}

.timer-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 8px;
}

.timer-row button {
  border: none;
  min-height: 42px;
  border-radius: 14px;
  background: var(--soft);
  color: var(--accent);
  font-weight: 900;
  cursor: pointer;
}

.practice-display {
  padding: 14px;
  border-radius: 18px;
  background: var(--card-solid);
  border: 1px solid var(--border);
  display: grid;
  gap: 4px;
}

.practice-display span {
  font-size: 38px;
  line-height: 1;
  font-weight: 950;
  letter-spacing: -0.06em;
  color: var(--accent);
}

.practice-display strong {
  font-size: 24px;
}

.practice-display small {
  color: var(--muted);
  line-height: 1.35;
}

.progression-button,
.lesson-button {
  border: 1px solid var(--border);
  background: var(--card-solid);
  color: var(--ink);
  border-radius: 16px;
  padding: 12px;
  text-align: left;
  cursor: pointer;
}

.progression-button strong,
.lesson-button strong {
  display: block;
}

.progression-button span,
.lesson-button span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  margin-top: 4px;
  line-height: 1.35;
}

.scale-card {
  grid-column: span 1;
}

.scale-controls {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  margin-bottom: 10px;
}

body.lefty .fretboard {
  transform: scaleX(-1);
}

body.lefty .fretboard text,
body.lefty .fretboard circle {
  transform-box: fill-box;
  transform-origin: center;
}

body.lefty .fretboard text {
  transform: scaleX(-1);
}

@media (max-width: 1160px) {
  .learning-lab {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 700px) {
  .learning-lab {
    grid-template-columns: 1fr;
  }

  .chord-actions {
    justify-content: stretch;
  }

  .chord-actions button {
    flex: 1 1 100%;
  }

  .timer-row {
    grid-template-columns: 1fr;
  }
}


/* v2.1 mode-based UX cleanup */

.mode-switcher {
  display: inline-flex;
  gap: 8px;
  padding: 8px;
  border-radius: 999px;
  background: var(--card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  margin-bottom: 18px;
  max-width: 100%;
  overflow-x: auto;
}

.mode-button {
  border: none;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  padding: 10px 16px;
  cursor: pointer;
  font-weight: 900;
  white-space: nowrap;
}

.mode-button.active {
  background: linear-gradient(180deg, var(--accent-2), var(--accent));
  color: #211100;
}

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

.mode-panel {
  margin-bottom: 16px;
}

.practice-mode {
  display: grid;
  grid-template-columns: 1.05fr 1fr 1fr;
  gap: 16px;
}

.scales-mode,
.compare-mode {
  display: grid;
  grid-template-columns: 1fr;
}

.mode-card {
  min-height: 100%;
}

.metronome-row {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 10px;
  align-items: center;
}

.metronome-row label {
  color: var(--muted);
  font-size: 13px;
  font-weight: 900;
}

.metronome-dot {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: var(--border);
  box-shadow: none;
}

.metronome-dot.tick {
  background: var(--accent);
  box-shadow: 0 0 0 8px var(--soft);
}

.view-toggle {
  display: inline-flex;
  gap: 6px;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: 999px;
  width: fit-content;
  background: var(--card-solid);
}

.view-toggle button {
  border: none;
  border-radius: 999px;
  padding: 8px 12px;
  background: transparent;
  color: var(--muted);
  font-weight: 900;
  cursor: pointer;
}

.view-toggle button.active {
  background: var(--soft);
  color: var(--accent);
}

.scale-fretboard {
  margin-top: 14px;
  display: none;
  overflow-x: auto;
}

.scale-fretboard.active {
  display: block;
}

.scale-fretboard svg {
  min-width: 640px;
  width: 100%;
  height: auto;
  display: block;
}

.compare-controls {
  margin-bottom: 14px;
}

.compare-result {
  display: grid;
  gap: 14px;
}

.compare-summary {
  padding: 14px;
  border-radius: 18px;
  background: var(--card-solid);
  border: 1px solid var(--border);
}

.compare-summary strong {
  display: block;
  font-size: 22px;
  margin-bottom: 6px;
}

.compare-summary span {
  color: var(--muted);
  line-height: 1.45;
}

.change-list {
  display: grid;
  gap: 10px;
}

.change-row {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 10px;
  padding: 12px;
  border-radius: 16px;
  background: var(--card-solid);
  border: 1px solid var(--border);
}

.change-row strong {
  color: var(--accent);
}

.change-row span {
  color: var(--muted);
}

.compact-diagrams {
  display: grid;
  grid-template-columns: repeat(2, minmax(220px, 1fr));
  gap: 14px;
}

.compact-diagram {
  padding: 12px;
  border-radius: 18px;
  border: 1px solid var(--border);
  background: var(--card-solid);
}

.compact-diagram h4 {
  margin: 0 0 10px;
}

.compact-diagram .fretboard {
  max-width: 250px;
  margin: 0 auto;
}

@media (max-width: 1160px) {
  .practice-mode {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 700px) {
  .mode-switcher {
    display: flex;
    width: 100%;
  }

  .mode-button {
    flex: 1 0 auto;
  }

  .metronome-row {
    grid-template-columns: 1fr;
  }

  .compact-diagrams {
    grid-template-columns: 1fr;
  }

  .change-row {
    grid-template-columns: 1fr;
  }
}