:root {
  color-scheme: dark;
  --bg: #0b0d10;
  --panel: #13171c;
  --panel-strong: #191e24;
  --border: #303740;
  --border-hover: #657180;
  --text: #f3f5f7;
  --muted: #9ea7b2;
  --blue: #1ba7e1;
  --orange: #f59e0b;
  --natural: #08090b;
  --accidental: #555d67;
  --tap: #d946ef;
  --warning: #fbbf24;
  --radius: 16px;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }

html { min-width: 320px; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
}

button,
select,
input { font: inherit; }

button,
select {
  border: 1px solid var(--border);
  background: var(--panel-strong);
  color: var(--text);
  border-radius: 10px;
  padding: 10px 12px;
}

button { cursor: pointer; }

button:hover { border-color: var(--border-hover); }

button:focus-visible,
select:focus-visible,
input:focus-visible {
  outline: 3px solid white;
  outline-offset: 2px;
}

.site-header,
.toolbar,
.legend,
main,
footer {
  width: min(1500px, calc(100% - 28px));
  margin-inline: auto;
}

.site-header {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  align-items: end;
  padding: 32px 0 18px;
}

.eyebrow,
.chart-family {
  margin: 0 0 6px;
  text-transform: uppercase;
  letter-spacing: 0.13em;
  font-size: 0.74rem;
  color: var(--muted);
  font-weight: 700;
}

.site-header h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 0.95;
}

.lede {
  max-width: 760px;
  margin: 12px 0 0;
  color: var(--muted);
}

.header-actions,
.card-actions {
  display: flex;
  gap: 9px;
  flex-wrap: wrap;
}

.primary {
  background: var(--blue);
  border-color: var(--blue);
  color: #05131b;
  font-weight: 800;
}

.toolbar {
  display: flex;
  align-items: end;
  gap: 12px;
  flex-wrap: wrap;
  padding: 14px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

label {
  display: grid;
  gap: 5px;
  color: var(--muted);
  font-size: 0.8rem;
}

.toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 4px;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  padding: 16px 2px;
  color: var(--muted);
  font-size: 0.82rem;
}

.legend span {
  display: flex;
  align-items: center;
  gap: 7px;
}

.swatch {
  display: inline-block;
  width: 16px;
  height: 16px;
  border: 1px solid #ffffff28;
  border-radius: 4px;
}

.swatch.root { background: var(--blue); }
.swatch.member { background: var(--orange); }
.swatch.natural { background: var(--natural); }
.swatch.accidental { background: var(--accidental); }
.swatch.selected { box-shadow: inset 0 0 0 3px var(--tap); }

main { padding-bottom: 28px; }

.recogniser {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: center;
  padding: 16px 18px;
  margin-bottom: 16px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.recogniser h2 {
  margin: 0;
  font-size: 1.3rem;
}

.recogniser p:last-child {
  margin: 4px 0 0;
  color: var(--muted);
}

.note-chips {
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.note-chip {
  padding: 6px 10px;
  background: var(--tap);
  border-color: transparent;
  color: white;
  border-radius: 999px;
  font-weight: 750;
}

.note-chip:hover {
  border-color: white;
}

.charts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 580px), 1fr));
  gap: 16px;
}

.empty-state {
  grid-column: 1 / -1;
  margin: 0;
  padding: 28px;
  text-align: center;
  color: var(--muted);
  background: var(--panel);
  border: 1px dashed var(--border);
  border-radius: var(--radius);
}

.chart-card {
  min-width: 0;
  padding: 14px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}

.chart-head {
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.chart-title {
  margin: 0;
  font-size: 1.35rem;
}

.chart-formula {
  margin: 5px 0 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.icon-button {
  width: 36px;
  height: 36px;
  padding: 0;
  display: grid;
  place-items: center;
  font-size: 1.3rem;
}

.chart-controls {
  display: grid;
  grid-template-columns: minmax(100px, 130px) minmax(0, 1fr);
  gap: 10px;
  margin: 14px 0;
}

.chart-controls select { min-width: 0; }

.voicing-warning {
  margin: -2px 0 12px;
  padding: 9px 10px;
  border: 1px solid #fbbf2455;
  border-radius: 9px;
  background: #fbbf2414;
  color: var(--warning);
  font-size: 0.78rem;
}

.grid-wrap {
  overflow-x: auto;
  padding-bottom: 3px;
  scrollbar-color: var(--border-hover) transparent;
}

.pad-grid {
  --columns: 13;
  --grid-min-width: 650px;
  display: grid;
  grid-template-columns: repeat(var(--columns), minmax(0, 1fr));
  gap: 5px;
  width: 100%;
  min-width: var(--grid-min-width);
}

.pad {
  position: relative;
  min-width: 0;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  border: 1px solid #ffffff24;
  border-radius: 7px;
  font-size: clamp(0.7rem, 1.2vw, 0.86rem);
  font-weight: 760;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

.pad.natural { background: var(--natural); }
.pad.accidental { background: var(--accidental); }
.pad.member { background: var(--orange); color: #171009; }
.pad.root { background: var(--blue); color: #06161f; }
.pad.tapped { box-shadow: inset 0 0 0 4px var(--tap); }

.pad .octave {
  position: absolute;
  right: 4px;
  bottom: 2px;
  font-size: 0.52rem;
  opacity: 0.68;
}

.pad-grid[data-layout="iphone"] .pad { font-size: 1rem; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: baseline;
  padding: 18px 0 28px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.85rem;
}

footer p { margin: 0; }

.credits { white-space: nowrap; }

.credits a {
  color: var(--text);
  text-decoration-color: var(--blue);
  text-underline-offset: 3px;
}

@media (max-width: 700px) {
  .site-header,
  .recogniser,
  footer {
    align-items: flex-start;
    flex-direction: column;
  }

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

  .toolbar { align-items: stretch; }
  .toolbar label { flex: 1 1 140px; }
  .toolbar > button { flex: 1 1 180px; }

  .recogniser .note-chips { justify-content: flex-start; }
  .chart-controls { grid-template-columns: 1fr; }
  .credits { white-space: normal; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; }
}