:root {
  --bg: #f7f7f7;
  --surface: #ffffff;
  --text: #2f2f2f;
  --muted: #6b6b6b;
  --line: #d9d9d9;
  --accent: #1f6fb2;
  --accent-bg: #dcefff;
  --note: #3a3a3a;
  --rest: #b5b5b5;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #2b2b2b;
    --surface: #363636;
    --text: #e8e8e8;
    --muted: #a9a9a9;
    --line: #4d4d4d;
    --accent: #8cc8ff;
    --accent-bg: #2f4a63;
    --note: #ececec;
    --rest: #777777;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, Ubuntu, sans-serif;
}

a { color: var(--accent); }

.top {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 20px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}

.brand { font-weight: 700; font-size: 20px; color: var(--text); text-decoration: none; }
.main-nav { display: flex; flex-wrap: wrap; gap: 4px 16px; flex: 1; }
.main-nav a { color: var(--text); text-decoration: none; }
.main-nav a:hover { color: var(--accent); }

.cta, .button {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 6px;
  background: var(--accent-bg);
  color: var(--text);
  text-decoration: none;
  font-weight: 600;
}
.cta:hover, .button:hover { outline: 2px solid var(--accent); }

main { max-width: 760px; margin: 0 auto; padding: 16px 16px 48px; }
.crumbs { font-size: 14px; color: var(--muted); }
.crumbs a { color: var(--muted); }
h1 { font-size: 32px; line-height: 1.25; margin: 12px 0 16px; }
h2 { font-size: 23px; margin-top: 36px; }
h3 { font-size: 18px; margin-top: 24px; }

table { border-collapse: collapse; width: 100%; font-size: 15px; }
th, td { border-bottom: 1px solid var(--line); padding: 6px 8px; text-align: left; vertical-align: top; }
code { font-size: 0.9em; }

.open { margin: 12px 0; }

.pages { list-style: none; padding: 0; }
.pages li { margin: 10px 0; }
.pages span { color: var(--muted); font-size: 15px; }

/* Rhythm grid: one row per measure, cell widths follow the durations. */
.rhythm {
  margin: 20px 0;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}
.measures { display: flex; flex-direction: column; gap: 10px; }
.measure { display: flex; align-items: flex-end; gap: 8px; }
.ts {
  font-weight: 700;
  line-height: 1.05;
  text-align: center;
  min-width: 1.4em;
  padding-bottom: 2px;
}
.cells { display: flex; align-items: flex-end; flex: 1; min-width: 0; border-left: 2px solid var(--line); border-right: 2px solid var(--line); }
.tuplet { display: flex; flex-direction: column; min-width: 0; }
.tuplet .bracket {
  font-size: 12px;
  font-style: italic;
  text-align: center;
  border: 1px solid var(--muted);
  border-bottom: none;
  margin: 0 4px 2px;
  height: 12px;
  line-height: 10px;
  color: var(--muted);
}
.tuplet .inner { display: flex; }
.cell {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
  padding: 0 2px;
  border-left: 1px solid transparent;
}
.cell.beat { border-left-color: var(--line); }
.cell i {
  display: block;
  width: 14px;
  height: 14px;
  margin: 4px 0;
  border-radius: 50%;
  background: var(--note);
}
.cell.rest i { width: 12px; height: 3px; margin: 10px 1px 9px; border-radius: 1px; background: var(--rest); }
.cell.accent i { box-shadow: 0 0 0 3px var(--accent-bg), 0 0 0 4px var(--accent); }
.cell b { font-weight: 500; font-size: 14px; white-space: nowrap; }
.cell.rest b { color: var(--rest); font-weight: 400; }
.cell.beat b { font-weight: 700; }
.rhythm figcaption { margin-top: 10px; font-size: 15px; color: var(--muted); }
.play { font-weight: 600; white-space: nowrap; }

footer {
  border-top: 1px solid var(--line);
  background: var(--surface);
  padding: 16px;
  font-size: 15px;
  color: var(--muted);
}
footer .groups { display: flex; flex-wrap: wrap; gap: 8px 40px; max-width: 760px; margin: 0 auto; }
footer h2 { font-size: 15px; margin: 8px 0 4px; color: var(--text); }
footer ul { list-style: none; padding: 0; margin: 0; }
footer p { max-width: 760px; margin: 16px auto 0; }

@media (max-width: 640px) {
  .main-nav { order: 3; flex-basis: 100%; }
  h1 { font-size: 27px; }
  .rhythm { padding: 10px 8px; }
  .cell b { font-size: 12px; }
}