:root {
  --bg: #0f1014;
  --panel: #1a1d24;
  --border: #2a2f3a;
  --fg: #e6e6e6;
  --muted: #8b94a3;
  --accent: #7cc4ff;
  --active: #ffd166;
  --shadow: 0 6px 20px rgba(0, 0, 0, 0.4);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  min-height: 100vh;
}

h1 {
  margin: 32px auto 4px;
  text-align: center;
  font-weight: 600;
  font-size: 1.6rem;
}

.subtitle {
  margin: 0 auto 24px;
  text-align: center;
  color: var(--muted);
  font-size: 0.95rem;
  padding: 0 16px;
}

.controls {
  max-width: 880px;
  margin: 0 auto 24px;
  padding: 16px 20px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  display: flex;
  flex-wrap: wrap;
  align-items: end;
  gap: 16px;
}

.controls label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.85rem;
  color: var(--muted);
  min-width: 90px;
}

.controls label.wide {
  flex: 1;
  min-width: 220px;
}

.controls label.check {
  flex-direction: row;
  align-items: center;
  min-width: auto;
  gap: 6px;
  padding-bottom: 8px;
  color: var(--fg);
}

.controls select,
.controls input[type="range"] {
  background: #0c0e13;
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 0.95rem;
}

.controls input[type="range"] {
  padding: 0;
  accent-color: var(--accent);
}

#playBtn {
  background: var(--accent);
  color: #061018;
  border: none;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 10px 22px;
  cursor: pointer;
  transition: filter 0.15s;
}

#playBtn:hover {
  filter: brightness(1.08);
}

#playBtn[data-state="playing"] {
  background: #ff6b8a;
}

.chord-row {
  max-width: 1040px;
  margin: 0 auto;
  padding: 0 16px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.chord-card {
  flex: 0 0 130px;
  min-height: 110px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 12px;
  text-align: center;
  transition: transform 0.15s, border-color 0.15s, background 0.15s;
  box-shadow: var(--shadow);
}

.chord-card.active {
  border-color: var(--active);
  background: #2a2418;
  transform: translateY(-4px);
}

.chord-roman {
  font-family: "Georgia", serif;
  font-style: italic;
  color: var(--muted);
  font-size: 0.95rem;
  margin-bottom: 4px;
}

.chord-name {
  font-size: 1.6rem;
  font-weight: 600;
  color: var(--fg);
  letter-spacing: 0.5px;
}

.chord-card.active .chord-name {
  color: var(--active);
}

.chord-tones {
  margin-top: 6px;
  font-size: 0.72rem;
  color: var(--muted);
  font-family: "SF Mono", Consolas, monospace;
}

footer {
  max-width: 700px;
  margin: 40px auto 24px;
  padding: 0 16px;
  color: var(--muted);
  text-align: center;
  font-size: 0.82rem;
}

footer code {
  background: #1a1d24;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 5px;
  font-family: "SF Mono", Consolas, monospace;
  font-size: 0.78rem;
}