/* strumtune · Figma 稿复刻（tokens: doc/design/2026-10-28/tokens.json）
   纸感底 + 烧橙强调 + 编辑风衬线 + 模拟调音器暗区 */
@font-face { font-family: 'Lora'; src: url('/assets/fonts/lora-400.woff2') format('woff2'); font-weight: 400; font-display: swap; }
@font-face { font-family: 'Lora'; src: url('/assets/fonts/lora-700.woff2') format('woff2'); font-weight: 700; font-display: swap; }
@font-face { font-family: 'Inter'; src: url('/assets/fonts/inter-400.woff2') format('woff2'); font-weight: 400; font-display: swap; }
@font-face { font-family: 'Inter'; src: url('/assets/fonts/inter-600.woff2') format('woff2'); font-weight: 600; font-display: swap; }
@font-face { font-family: 'IBM Plex Mono'; src: url('/assets/fonts/plex-mono-400.woff2') format('woff2'); font-weight: 400; font-display: swap; }
@font-face { font-family: 'IBM Plex Mono'; src: url('/assets/fonts/plex-mono-600.woff2') format('woff2'); font-weight: 600; font-display: swap; }

:root {
  --paper: #F6F1E7; --surface: #FFFCF5; --ink: #292720; --muted: #746D60;
  --line: #D8D0C0; --accent: #B64A2D; --pale-accent: #F0DFD2;
  --dark: #302F28; --dark-line: #57564B; --light: #EEE8D9;
  --green: #53745B; --pale-green: #DFE6D6; --brass: #BDA06A;
  --serif: 'Lora', Georgia, serif; --sans: 'Inter', -apple-system, sans-serif; --mono: 'IBM Plex Mono', monospace;
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--paper); color: var(--ink); font-family: var(--sans); font-size: 16px; line-height: 1.6; }
main { max-width: 1120px; margin: 0 auto; padding: 0 24px 64px; }
h1, h2, h3 { font-family: var(--serif); line-height: 1.15; font-weight: 700; margin: 0 0 16px; }
h1 { font-size: clamp(36px, 6vw, 56px); }
h2 { font-size: clamp(24px, 4vw, 32px); margin-top: 48px; }
a { color: var(--accent); }
.kicker { font-family: var(--mono); font-size: 11px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--accent); display: block; margin-bottom: 12px; }
.kicker.muted { color: var(--muted); }
.lede { font-size: 18px; color: var(--muted); max-width: 640px; }

/* header/footer */
.site-header { display: flex; align-items: center; gap: 28px; padding: 18px 24px; max-width: 1120px; margin: 0 auto; }
.wordmark { font-family: var(--serif); font-weight: 700; font-size: 32px; color: var(--ink); text-decoration: none; }
.wordmark.small { font-size: 25px; }
.site-nav { display: flex; gap: 20px; margin-left: auto; }
.site-nav a { color: var(--ink); text-decoration: none; font-weight: 600; font-size: 14px; }
.site-nav a[aria-current="page"] { color: var(--accent); }
.free-badge { font-family: var(--mono); font-size: 11px; color: var(--muted); }
.site-footer { border-top: 1px solid var(--line); max-width: 1120px; margin: 64px auto 0; padding: 32px 24px 48px; display: flex; flex-wrap: wrap; gap: 24px; align-items: baseline; }
.site-footer nav { display: flex; gap: 18px; margin-left: auto; }
.site-footer nav a { color: var(--ink); text-decoration: none; font-size: 13px; }
.footer-tag { color: var(--muted); font-size: 12px; margin: 4px 0 0; }
.footer-copy { font-family: var(--mono); font-size: 11px; color: var(--muted); width: 100%; }
.crumbs ol { list-style: none; display: flex; gap: 8px; padding: 0; margin: 16px 0 24px; font-size: 13px; color: var(--muted); }
.crumbs li + li::before { content: '/'; margin-right: 8px; color: var(--line); }
.crumbs a { color: var(--muted); text-decoration: none; }

/* 暗色调音器区（首页 hero + /tuner/） */
.tuner-hero { background: var(--dark); color: var(--light); border-radius: 16px; padding: 40px; margin: 24px 0 48px; }
.tuner-hero h1, .tuner-hero h2 { color: var(--light); }
.tuner-hero .kicker { color: var(--brass); }
.tuner-panel { display: grid; grid-template-columns: 120px 1fr 200px; gap: 32px; align-items: center; margin-top: 24px; }
.string-guide { display: flex; flex-direction: column; gap: 10px; }
.string-guide .sg-note { font-family: var(--mono); font-size: 12px; color: var(--brass); }
.string-guide .sg-string { display: flex; align-items: center; gap: 10px; padding: 8px 10px; border: 1px solid var(--dark-line); border-radius: 8px; cursor: pointer; background: transparent; color: var(--light); width: 100%; text-align: left; font-family: var(--mono); font-size: 13px; }
.string-guide .sg-string.active { border-color: var(--accent); background: rgba(182, 74, 45, 0.15); }
.gauge-wrap { text-align: center; }
.gauge-note { font-family: var(--serif); font-size: 64px; font-weight: 700; color: var(--light); }
.gauge-note .oct { font-size: 28px; color: var(--brass); }
.gauge-hz { font-family: var(--mono); font-size: 13px; color: var(--brass); margin-top: 4px; }
.gauge-cents { font-family: var(--mono); font-size: 13px; margin-top: 8px; }
.gauge-cents .flat { color: #d98b73; } .gauge-cents .sharp { color: #d98b73; } .gauge-cents .ok { color: var(--green); }
.tuner-controls { display: flex; flex-direction: column; gap: 12px; }
.btn { display: inline-block; border: none; border-radius: 8px; padding: 12px 20px; font-family: var(--sans); font-weight: 600; font-size: 14px; cursor: pointer; text-decoration: none; text-align: center; }
.btn-primary { background: var(--accent); color: var(--surface); }
.btn-ghost { background: transparent; color: var(--light); border: 1px solid var(--dark-line); }
.on-light .btn-ghost, .btn-ghost.on-light { color: var(--ink); border-color: var(--line); }
.tuner-hint { font-size: 13px; color: var(--brass); }
.mic-note { font-family: var(--mono); font-size: 10px; color: var(--brass); letter-spacing: 0.06em; }

/* 工具卡片 */
.tool-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 16px; margin: 24px 0; }
.tool-card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 20px; text-decoration: none; color: var(--ink); transition: border-color 0.15s; }
.tool-card:hover { border-color: var(--accent); }
.tool-card h3 { font-size: 20px; margin-bottom: 6px; }
.tool-card p { margin: 0; font-size: 14px; color: var(--muted); }
.tool-card .tc-tag { font-family: var(--mono); font-size: 10px; color: var(--accent); text-transform: uppercase; letter-spacing: 0.06em; }

/* 和弦卡片 */
.chord-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 16px; margin: 24px 0; }
.chord-card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 12px; text-align: center; margin: 0; scroll-margin-top: 100px; }
.chord-card-name { font-family: var(--serif); font-size: 22px; font-weight: 700; }
.chord-card-inst { font-family: var(--mono); font-size: 9px; color: var(--muted); text-transform: uppercase; }
.cd-string { stroke: var(--muted); stroke-width: 1; }
.cd-fret { stroke: var(--line); stroke-width: 2; }
.cd-nut { stroke: var(--ink); stroke-width: 4; }
.cd-dot { fill: var(--accent); }
.cd-finger { fill: var(--surface); font-family: var(--sans); font-weight: 600; font-size: 9px; }
.cd-open, .cd-mute { fill: var(--muted); font-size: 11px; }
.cd-barre { fill: none; stroke: var(--accent); stroke-width: 3; stroke-linecap: round; }
.cd-fretnum { fill: var(--muted); font-family: var(--mono); font-size: 9px; }

.filter-row { display: flex; flex-wrap: wrap; gap: 8px; margin: 16px 0; align-items: center; }
.chip { border: 1px solid var(--line); background: var(--surface); border-radius: 999px; padding: 6px 14px; font-family: var(--sans); font-size: 13px; cursor: pointer; color: var(--ink); }
.chip.active { background: var(--accent); border-color: var(--accent); color: var(--surface); }
.chip-label { font-family: var(--mono); font-size: 11px; color: var(--muted); margin-right: 4px; }

/* 歌曲页 */
.song-line { display: flex; gap: 16px; padding: 10px 0; border-bottom: 1px solid var(--line); align-items: baseline; }
.song-line .ch { font-family: var(--mono); font-weight: 600; color: var(--accent); min-width: 48px; }
.prog-table td, .prog-table th { padding: 8px 14px; text-align: left; border-bottom: 1px solid var(--line); }
.prog-table { border-collapse: collapse; margin: 16px 0; }
.prog-table .ch a { font-family: var(--mono); font-weight: 600; }

/* FAQ */
.faq details { border-bottom: 1px solid var(--line); padding: 14px 0; }
.faq summary { cursor: pointer; font-weight: 600; font-size: 16px; }
.faq details p { color: var(--muted); margin: 10px 0 0; }

/* 内容排版 */
.content-block { max-width: 720px; }
.byline { font-size: 13px; color: var(--muted); margin: -8px 0 24px; }
.note-block { background: var(--pale-accent); border-radius: 12px; padding: 20px 24px; margin: 24px 0; }
.note-block.green { background: var(--pale-green); }
.cta-block { text-align: center; padding: 40px 24px; background: var(--surface); border: 1px solid var(--line); border-radius: 16px; margin: 40px 0; }
.cta-block h2 { margin-top: 0; }

/* 工具交互区 */
.tool-panel { background: var(--surface); border: 1px solid var(--line); border-radius: 16px; padding: 28px; margin: 24px 0; }
.tool-row { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin: 12px 0; }
input[type="number"], input[type="text"], select { font-family: var(--sans); font-size: 14px; padding: 10px 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--surface); color: var(--ink); }
input[type="range"] { accent-color: var(--accent); }
.output { font-family: var(--mono); background: var(--paper); border: 1px solid var(--line); border-radius: 8px; padding: 16px; white-space: pre-wrap; margin: 16px 0; }
.beat-flash { width: 18px; height: 18px; border-radius: 50%; background: var(--line); display: inline-block; }
.beat-flash.on { background: var(--accent); }
.tab-editor { width: 100%; min-height: 260px; font-family: var(--mono); font-size: 14px; background: var(--paper); color: var(--ink); border: 1px solid var(--line); border-radius: 8px; padding: 16px; line-height: 1.9; }

/* 移动端 */
@media (max-width: 720px) {
  .tuner-panel { grid-template-columns: 1fr; }
  .string-guide { flex-direction: row; flex-wrap: wrap; }
  .string-guide .sg-string { width: auto; }
  .site-header { flex-wrap: wrap; gap: 12px; }
  .site-nav { margin-left: 0; width: 100%; }
  main { padding: 0 16px 48px; }
  .tuner-hero { padding: 24px; }
}