:root {
  --bg: #14110f;
  --bg2: #1d1916;
  --card: #241f1b;
  --card2: #2c2620;
  --border: #3a322a;
  --text: #ece5db;
  --muted: #a89c8c;
  --accent: #e8a33d;
  --accent2: #c9762a;
  --good: #6fc46f;
  --bad: #e06a5a;
  /* Scotty's rainbow degree colors */
  --deg1: #e64545;
  --deg2: #ef8c2f;
  --deg3: #e6c937;
  --deg4: #58b85c;
  --deg5: #4f8fe0;
  --deg6: #5b5bd6;
  --deg7: #a25bd6;
  --radius: 10px;
  font-size: 16px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.55;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

#topbar {
  position: sticky; top: 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0.6rem 1.2rem;
  background: rgba(20,17,15,0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
#brand { color: var(--text); font-weight: 700; font-size: 1.05rem; }
#brand em { color: var(--muted); font-style: normal; font-weight: 400; font-size: 0.85rem; margin-left: 0.4rem; }
#brand:hover { text-decoration: none; }
#progress-pill {
  background: var(--card2); border: 1px solid var(--border);
  border-radius: 999px; padding: 0.25rem 0.8rem; font-size: 0.85rem; color: var(--muted);
}

#app { max-width: 1000px; margin: 0 auto; padding: 1.5rem 1.2rem 4rem; }
footer { max-width: 1000px; margin: 0 auto; padding: 1rem 1.2rem 2.5rem; color: var(--muted); font-size: 0.8rem; border-top: 1px solid var(--border); }

/* ---------- Home ---------- */
.hero { padding: 1.5rem 0 0.5rem; }
.hero h1 { font-size: 2rem; margin: 0 0 0.4rem; }
.hero p { color: var(--muted); max-width: 46rem; margin: 0.3rem 0; }
.hero .hero-links { margin-top: 0.8rem; display: flex; gap: 0.8rem; flex-wrap: wrap; }
.part-head { margin: 2rem 0 0.8rem; }
.part-head h2 { margin: 0; font-size: 1.2rem; color: var(--accent); }
.part-head p { margin: 0.2rem 0 0; color: var(--muted); font-size: 0.9rem; }
.lesson-grid {
  display: grid; gap: 0.7rem;
  grid-template-columns: repeat(auto-fill, minmax(290px, 1fr));
}
.lesson-card {
  display: block; background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 0.8rem 1rem; color: var(--text);
  transition: border-color 0.15s, transform 0.15s;
}
.lesson-card:hover { border-color: var(--accent); text-decoration: none; transform: translateY(-2px); }
.lesson-card .num { color: var(--accent); font-weight: 700; font-size: 0.8rem; letter-spacing: 0.06em; }
.lesson-card h3 { margin: 0.15rem 0 0.3rem; font-size: 1.02rem; }
.lesson-card .tagline { color: var(--muted); font-size: 0.85rem; margin: 0; }
.lesson-card .status { margin-top: 0.5rem; font-size: 0.78rem; color: var(--muted); display: flex; gap: 0.7rem; }
.lesson-card .status .done { color: var(--good); }

/* ---------- Lesson page ---------- */
.lesson-nav { display: flex; justify-content: space-between; align-items: center; gap: 1rem; margin-bottom: 1rem; font-size: 0.9rem; }
.lesson-nav a { color: var(--muted); }
.lesson-nav a:hover { color: var(--accent); }
.lesson-header .num { color: var(--accent); font-weight: 700; letter-spacing: 0.08em; font-size: 0.85rem; }
.lesson-header h1 { margin: 0.2rem 0 0.4rem; font-size: 1.7rem; }
.lesson-header .tagline { color: var(--muted); margin: 0 0 1rem; font-size: 1.02rem; }

.video-wrap {
  position: relative; width: 100%; aspect-ratio: 16 / 9;
  background: #000; border-radius: var(--radius); overflow: hidden;
  border: 1px solid var(--border); margin-bottom: 0.5rem;
}
.video-wrap iframe, .video-wrap .video-poster { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }
.video-poster { cursor: pointer; display: flex; align-items: center; justify-content: center; background-size: cover; background-position: center; }
.video-poster .play-btn {
  width: 74px; height: 52px; background: rgba(20,17,15,0.85); border: 2px solid var(--accent);
  border-radius: 14px; display: flex; align-items: center; justify-content: center;
  font-size: 1.4rem; color: var(--accent); transition: transform 0.15s;
}
.video-poster:hover .play-btn { transform: scale(1.1); }
.video-sub { display: flex; justify-content: space-between; color: var(--muted); font-size: 0.85rem; margin-bottom: 1.4rem; flex-wrap: wrap; gap: 0.5rem; }

section.block { margin: 1.6rem 0; }
section.block > h2 { font-size: 1.15rem; border-bottom: 1px solid var(--border); padding-bottom: 0.4rem; margin-bottom: 0.8rem; }
.summary p { margin: 0.6rem 0; }
.keypoints { list-style: none; padding: 0; margin: 0; display: grid; gap: 0.45rem; }
.keypoints li { background: var(--card); border: 1px solid var(--border); border-left: 3px solid var(--accent); border-radius: 6px; padding: 0.5rem 0.8rem; font-size: 0.93rem; }

.widget {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 1rem; margin: 1rem 0;
}
.widget > h3 { margin: 0 0 0.2rem; font-size: 1.05rem; color: var(--accent); }
.widget > p.note { margin: 0 0 0.8rem; color: var(--muted); font-size: 0.88rem; }
.controls { display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; margin-bottom: 0.8rem; }
.controls label { font-size: 0.85rem; color: var(--muted); display: flex; align-items: center; gap: 0.35rem; }
select, button, input[type="number"] {
  background: var(--card2); color: var(--text); border: 1px solid var(--border);
  border-radius: 6px; padding: 0.35rem 0.6rem; font-size: 0.9rem; font-family: inherit;
}
button { cursor: pointer; }
button:hover { border-color: var(--accent); }
button.primary { background: var(--accent); color: #1a1308; font-weight: 600; border-color: var(--accent); }
button.primary:hover { background: #f4b455; }
button:disabled { opacity: 0.45; cursor: default; }
input[type="range"] { accent-color: var(--accent); }

/* fretboard */
.fretboard-svg { width: 100%; height: auto; display: block; }
.fb-note { cursor: pointer; }
.legend { display: flex; flex-wrap: wrap; gap: 0.5rem 0.9rem; margin-top: 0.6rem; font-size: 0.8rem; color: var(--muted); }
.legend .key { display: inline-flex; align-items: center; gap: 0.3rem; }
.legend .dot { width: 13px; height: 13px; border-radius: 50%; display: inline-block; }

/* chord diagrams */
.chord-row { display: flex; flex-wrap: wrap; gap: 0.8rem; }
.chord-dia { background: var(--card2); border: 1px solid var(--border); border-radius: 8px; padding: 0.5rem 0.6rem 0.3rem; cursor: pointer; transition: border-color 0.15s; text-align: center; }
.chord-dia:hover { border-color: var(--accent); }
.chord-dia .nm { font-size: 0.85rem; font-weight: 600; margin-bottom: 0.15rem; }
.chord-dia .sub { font-size: 0.72rem; color: var(--muted); }

/* tables */
table.theory { border-collapse: collapse; width: 100%; font-size: 0.9rem; }
table.theory th, table.theory td { border: 1px solid var(--border); padding: 0.4rem 0.6rem; text-align: left; }
table.theory th { background: var(--card2); color: var(--muted); font-weight: 600; }
table.theory tr.clickable { cursor: pointer; }
table.theory tr.clickable:hover { background: var(--card2); }
table.theory tr.hl { background: rgba(232,163,61,0.15); }

/* quiz */
.quiz-q { background: var(--card2); border: 1px solid var(--border); border-radius: 8px; padding: 0.8rem 1rem; margin: 0.7rem 0; }
.quiz-q .qt { font-weight: 600; margin-bottom: 0.6rem; }
.quiz-choices { display: grid; gap: 0.4rem; }
.quiz-choices button { text-align: left; padding: 0.5rem 0.7rem; }
.quiz-choices button.correct { border-color: var(--good); background: rgba(111,196,111,0.15); }
.quiz-choices button.wrong { border-color: var(--bad); background: rgba(224,106,90,0.15); }
.quiz-explain { margin-top: 0.5rem; font-size: 0.85rem; color: var(--muted); }
.quiz-score { font-weight: 700; margin-top: 0.8rem; }

/* practice checklist */
.practice-list { list-style: none; padding: 0; margin: 0; display: grid; gap: 0.4rem; }
.practice-list li { display: flex; gap: 0.6rem; align-items: flex-start; background: var(--card); border: 1px solid var(--border); border-radius: 6px; padding: 0.5rem 0.8rem; font-size: 0.92rem; cursor: pointer; }
.practice-list li.done { color: var(--muted); text-decoration: line-through; }
.practice-list li input { margin-top: 0.25rem; accent-color: var(--good); }

.complete-bar { display: flex; align-items: center; gap: 1rem; margin: 2rem 0 0; padding: 1rem; background: var(--card); border: 1px solid var(--border); border-radius: var(--radius); }
.complete-bar.is-done { border-color: var(--good); }
.complete-bar .msg { color: var(--muted); font-size: 0.9rem; }

/* circle of fifths */
.cof-wrap { display: flex; flex-wrap: wrap; gap: 1.2rem; align-items: flex-start; }
.cof-svg { flex: 0 0 320px; max-width: 100%; }
.cof-info { flex: 1; min-width: 250px; font-size: 0.92rem; }
.cof-seg { cursor: pointer; }
.cof-seg:hover text { fill: var(--accent); }

/* metronome / players */
.beat-lights { display: flex; gap: 0.5rem; margin: 0.6rem 0; }
.beat-lights .b { width: 22px; height: 22px; border-radius: 50%; background: var(--card2); border: 1px solid var(--border); }
.beat-lights .b.on { background: var(--accent); border-color: var(--accent); }
.beat-lights .b.on.accent { background: var(--deg1); border-color: var(--deg1); }
.prog-cells { display: flex; flex-wrap: wrap; gap: 0.4rem; margin: 0.6rem 0; }
.prog-cells .cell { min-width: 64px; text-align: center; background: var(--card2); border: 1px solid var(--border); border-radius: 6px; padding: 0.45rem 0.5rem; font-size: 0.9rem; }
.prog-cells .cell.now { border-color: var(--accent); background: rgba(232,163,61,0.18); }
.prog-cells .cell .rn { color: var(--muted); font-size: 0.75rem; display: block; }

/* strum patterns */
.strum-grid { display: grid; grid-auto-flow: column; gap: 0.3rem; justify-content: start; margin: 0.6rem 0; }
.strum-grid .sc { width: 44px; text-align: center; }
.strum-grid .ct { color: var(--muted); font-size: 0.8rem; }
.strum-grid .arrow { font-size: 1.3rem; height: 1.6rem; }
.strum-grid .sc.now .arrow { color: var(--accent); }

.pill { display: inline-block; background: var(--card2); border: 1px solid var(--border); border-radius: 999px; padding: 0.1rem 0.6rem; font-size: 0.78rem; color: var(--muted); }
.feedback { min-height: 1.4rem; font-size: 0.92rem; margin-top: 0.4rem; }
.feedback.good { color: var(--good); }
.feedback.bad { color: var(--bad); }

.interval-table-wrap { overflow-x: auto; }

@media (max-width: 640px) {
  #brand span { display: none; }
  .hero h1 { font-size: 1.5rem; }
}