/* ==================================================================
   design tokens
   コンセプト: コア(トア)材のウクレレボディ × 真鍮パーツの楽器パネル。
   既存アプリ群（五度圏コンパス等）のダークな計器盤トーンを踏襲しつつ、
   このアプリだけの合図として「フットスイッチ型のGenerateボタン」を signature に据える。
   ================================================================== */
:root {
  --bg: #17130f;
  --surface: #221b14;
  --surface-raised: #2b2219;
  --border: #3a2f24;

  --accent: #d98a3d;        /* コア材アンバー */
  --accent-strong: #f0a350;
  --accent-ink: #2a1608;    /* アンバー地に乗せる文字色 */

  --accent-secondary: #7ea690; /* 真鍮の緑青（セカンダリ用に温存。次ステップの理論パネルで使用予定） */

  --text: #f2e9da;
  --text-muted: #a89685;
  --text-faint: #6d5f4f;

  --font-display: 'Shippori Mincho', serif;
  --font-body: 'Zen Kaku Gothic New', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --radius-panel: 18px;
  --radius-control: 10px;

  color-scheme: dark;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
}

body {
  background-image:
    radial-gradient(circle at 15% -10%, rgba(217, 138, 61, 0.10), transparent 45%),
    radial-gradient(circle at 90% 0%, rgba(126, 166, 144, 0.06), transparent 40%);
}

.workbench {
  max-width: 720px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

/* ------------------------------------------------------------ header */

.workbench__header {
  margin-bottom: 28px;
}

.eyebrow {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.16em;
  color: var(--accent);
  text-transform: uppercase;
}

.title {
  margin: 0 0 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(28px, 6vw, 40px);
  line-height: 1.3;
  letter-spacing: 0.02em;
}

.title__break { display: none; }

.subtitle {
  margin: 0;
  color: var(--text-muted);
  font-size: 14px;
  line-height: 1.7;
}

/* ------------------------------------------------------------ control panel */

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-panel);
  padding: 20px 20px 24px;
  box-shadow: 0 20px 40px -24px rgba(0, 0, 0, 0.6), inset 0 1px 0 rgba(255, 255, 255, 0.03);
}

.panel__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px 14px;
  margin-bottom: 20px;
}

.control {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.control--tempo {
  grid-column: 1 / -1;
}

.control__label {
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.control__value {
  font-family: var(--font-mono);
  color: var(--accent-strong);
}

.control__select {
  appearance: none;
  width: 100%;
  padding: 10px 34px 10px 12px;
  background: var(--surface-raised) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='6'%3E%3Cpath d='M0 0 L5 6 L10 0' fill='none' stroke='%23a89685' stroke-width='1.4'/%3E%3C/svg%3E") no-repeat right 12px center;
  border: 1px solid var(--border);
  border-radius: var(--radius-control);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 14px;
}

.control__select:focus-visible,
.control__range:focus-visible,
.footswitch:focus-visible {
  outline: 2px solid var(--accent-strong);
  outline-offset: 2px;
}

.control__range {
  width: 100%;
  accent-color: var(--accent);
  height: 28px;
}

/* ------------------------------------------------------------ footswitch (signature element) */

.footswitch {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  width: 100%;
  padding: 16px;
  background: linear-gradient(180deg, var(--accent-strong), var(--accent));
  border: none;
  border-radius: 999px;
  color: var(--accent-ink);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.12em;
  cursor: pointer;
  box-shadow: 0 10px 22px -10px rgba(217, 138, 61, 0.55), inset 0 -3px 0 rgba(0, 0, 0, 0.18);
  transition: transform 120ms ease, box-shadow 120ms ease;
}

.footswitch:hover {
  transform: translateY(-1px);
}

.footswitch:active {
  transform: translateY(1px);
  box-shadow: 0 4px 10px -6px rgba(217, 138, 61, 0.55), inset 0 2px 0 rgba(0, 0, 0, 0.18);
}

.footswitch__led {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: rgba(42, 22, 8, 0.35);
  box-shadow: inset 0 0 0 1px rgba(42, 22, 8, 0.4);
  transition: background 150ms ease, box-shadow 150ms ease;
}

.footswitch.is-active .footswitch__led {
  background: #ffe9b8;
  box-shadow: 0 0 8px 2px rgba(255, 233, 184, 0.9);
}

/* ------------------------------------------------------------ result */

.result {
  margin-top: 28px;
}

.result__placeholder {
  color: var(--text-faint);
  font-size: 13px;
  text-align: center;
  padding: 40px 0;
}

.result__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-bottom: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-muted);
}

.result__meta strong {
  color: var(--text);
}

/* ------------------------------------------------------------ play button */

.play-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  padding: 12px;
  margin-bottom: 16px;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text);
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 13px;
  letter-spacing: 0.08em;
  cursor: pointer;
  transition: border-color 120ms ease, color 120ms ease;
}

.play-button:hover {
  border-color: var(--accent);
  color: var(--accent-strong);
}

.play-button:focus-visible {
  outline: 2px solid var(--accent-strong);
  outline-offset: 2px;
}

.play-button__icon {
  width: 0;
  height: 0;
  border-style: solid;
  border-width: 6px 0 6px 10px;
  border-color: transparent transparent transparent currentColor;
}

.play-button.is-playing .play-button__icon {
  width: 10px;
  height: 12px;
  border-style: none;
  background:
    linear-gradient(currentColor, currentColor) 0 0 / 3px 12px no-repeat,
    linear-gradient(currentColor, currentColor) 7px 0 / 3px 12px no-repeat;
}

.play-button.is-playing {
  border-color: var(--accent);
  color: var(--accent-strong);
}

/* コード進行の再生中に、今鳴っているコードカードをハイライトする */
.chord-card.is-playing {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px rgba(217, 138, 61, 0.35), 0 10px 20px -14px rgba(217, 138, 61, 0.6);
  transform: translateY(-2px);
  transition: transform 120ms ease, box-shadow 120ms ease, border-color 120ms ease;
}

.chord-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 10px;
}

.chord-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px 12px 12px;
  text-align: center;
}

.chord-card__roman {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.06em;
  margin-bottom: 2px;
}

.chord-card__label {
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 20px;
  color: var(--text);
  margin-bottom: 10px;
}

.chord-card__diagram {
  display: block;
  margin: 0 auto 8px;
}

.chord-card__function {
  font-size: 10px;
  color: var(--text-faint);
  letter-spacing: 0.04em;
}

.chord-card__frets {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

/* ------------------------------------------------------------ theory toggle（なぜこのコード？） */

.theory-toggle {
  margin-top: 10px;
  text-align: left;
  border-top: 1px dashed var(--border);
  padding-top: 8px;
}

.theory-toggle summary {
  cursor: pointer;
  font-size: 10px;
  color: var(--accent-secondary);
  letter-spacing: 0.03em;
  list-style: none;
}

.theory-toggle summary::-webkit-details-marker { display: none; }

.theory-toggle summary::before {
  content: '▸ ';
}

.theory-toggle[open] summary::before {
  content: '▾ ';
}

.theory-toggle__body {
  margin-top: 6px;
  font-size: 11px;
  line-height: 1.7;
  color: var(--text-muted);
}

/* ------------------------------------------------------------ もっと〇〇 ボタン */

.more-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.more-button {
  padding: 8px 14px;
  background: var(--surface-raised);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 12px;
  cursor: pointer;
  transition: border-color 120ms ease, color 120ms ease;
}

.more-button:hover {
  border-color: var(--accent);
  color: var(--accent-strong);
}

.more-button:focus-visible {
  outline: 2px solid var(--accent-strong);
  outline-offset: 2px;
}

/* ------------------------------------------------------------ responsive / a11y */

@media (min-width: 560px) {
  .title__break { display: inline; }
  .panel__grid { grid-template-columns: 1fr 1fr 1fr 1fr; }
  .control--tempo { grid-column: auto; }
}

@media (prefers-reduced-motion: reduce) {
  .footswitch { transition: none; }
}