:root {
  --bg: #f7f8fc;
  --surface: #ffffff;
  --fg: #1b1f2a;
  --muted: #5d6475;
  --border: #e1e4ee;
  --accent: #4f46e5;
  --accent-soft: #eceafe;
  --good: #16a34a;
  --good-soft: #dcfce7;
  --bad: #dc2626;
  --bad-soft: #fee2e2;
  --warn: #f59e0b;
  --code-bg: #f1f3f8;
  --shadow: 0 1px 2px rgba(20, 24, 40, .06), 0 8px 24px rgba(20, 24, 40, .06);
  --om: #2563eb; --ar: #d97706; --gl: #7c3aed;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0e1119; --surface: #161a25; --fg: #e8ebf3; --muted: #9aa2b5; --border: #2a3040;
    --accent: #8b85ff; --accent-soft: #24224a; --good: #4ade80; --good-soft: #12301f;
    --bad: #f87171; --bad-soft: #3a1717; --code-bg: #1e2331;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .25);
    --om: #60a5fa; --ar: #fbbf24; --gl: #a78bfa;
  }
}
:root[data-theme="dark"] {
  --bg: #0e1119; --surface: #161a25; --fg: #e8ebf3; --muted: #9aa2b5; --border: #2a3040;
  --accent: #8b85ff; --accent-soft: #24224a; --good: #4ade80; --good-soft: #12301f;
  --bad: #f87171; --bad-soft: #3a1717; --code-bg: #1e2331;
  --shadow: 0 1px 2px rgba(0, 0, 0, .3), 0 8px 24px rgba(0, 0, 0, .25);
  --om: #60a5fa; --ar: #fbbf24; --gl: #a78bfa;
}
.course-scm { --accent: #0d9488; --accent-soft: #d5f5f1; }
:root[data-theme="dark"] .course-scm { --accent: #2dd4bf; --accent-soft: #123532; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .course-scm { --accent: #2dd4bf; --accent-soft: #123532; }
}

* { box-sizing: border-box; }
html { scroll-padding-top: 64px; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  color: var(--fg);
  background: var(--bg);
  line-height: 1.55;
}
a { color: var(--accent); }
button { font: inherit; color: inherit; }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.center { text-align: center; }
code { background: var(--code-bg); padding: 1px 5px; border-radius: 4px; font-size: .9em; }

/* ---------- top bar ---------- */
.lbar {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; gap: 10px;
  padding: 10px 16px;
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.brand { font-size: 17px; text-decoration: none; color: var(--fg); white-space: nowrap; }
.brand-mark { color: var(--accent); }
.tabs { display: flex; gap: 4px; flex: 1; justify-content: center; }
.tabs a {
  padding: 6px 12px; border-radius: 999px; text-decoration: none; color: var(--muted); font-size: 14px; white-space: nowrap;
}
.tabs a:hover { background: var(--code-bg); color: var(--fg); }
.tabs a.on { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.pill-btn {
  border: 1px solid var(--border); background: var(--surface); border-radius: 999px;
  padding: 5px 11px; font-size: 14px; cursor: pointer; text-decoration: none; color: var(--fg); white-space: nowrap;
}
.pill-btn:hover { border-color: var(--accent); }

#app { max-width: 1080px; margin: 0 auto; padding: 24px 16px 80px; }

.cta, .primary, .ghost {
  display: inline-block; border-radius: 10px; padding: 10px 18px; font-size: 15px; font-weight: 600;
  cursor: pointer; text-decoration: none; border: 1px solid transparent; transition: transform .1s, box-shadow .15s;
}
.cta, .primary { background: var(--accent); color: #fff; }
.cta:hover, .primary:hover:not(:disabled) { transform: translateY(-1px); box-shadow: 0 6px 16px color-mix(in srgb, var(--accent) 35%, transparent); }
.ghost { background: var(--surface); border-color: var(--border); }
.ghost:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
button:disabled { opacity: .4; cursor: default; }
:root[data-theme="dark"] .cta, :root[data-theme="dark"] .primary { color: #0e1119; }

/* ---------- hero ---------- */
.hero {
  display: flex; gap: 24px; align-items: center; justify-content: space-between; flex-wrap: wrap;
  padding: 28px; border-radius: 20px; background: var(--surface); box-shadow: var(--shadow);
  background-image: radial-gradient(circle at 100% 0, var(--accent-soft), transparent 55%);
}
.eyebrow { text-transform: uppercase; letter-spacing: .08em; font-size: 12px; font-weight: 700; color: var(--accent); margin: 0 0 6px; }
.hero h1 { margin: 0 0 4px; font-size: clamp(22px, 4vw, 30px); line-height: 1.2; }
.hero p { margin: 0 0 18px; }
.stats { display: flex; gap: 12px; flex-wrap: wrap; }
.stat {
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 4px;
  min-width: 108px; padding: 12px; border-radius: 14px; background: var(--bg); text-decoration: none; color: var(--fg);
}
.stat b { font-size: 28px; line-height: 64px; }
.stat span { font-size: 12px; color: var(--muted); }
.ring-bg { fill: none; stroke: var(--border); stroke-width: 7; }
.ring-fg { fill: none; stroke: var(--accent); stroke-width: 7; stroke-linecap: round; transform: rotate(-90deg); transform-origin: center; transition: stroke-dashoffset .8s; }
.ring text { font-size: 14px; font-weight: 700; fill: var(--fg); }

/* ---------- course switch ---------- */
.course-switch {
  display: flex; gap: 8px; margin: 28px auto 8px; padding: 5px; border-radius: 14px; background: var(--surface);
  box-shadow: var(--shadow); width: fit-content; max-width: 100%;
}
.course-switch button {
  border: 0; background: none; padding: 9px 16px; border-radius: 10px; cursor: pointer; display: flex; gap: 8px; align-items: center;
}
.course-switch button small { color: var(--muted); font-size: 12px; }
.course-switch button.on { background: var(--accent); color: #fff; }
.course-switch button.on small { color: rgba(255, 255, 255, .8); }
.course-switch button[data-c="scm"].on { background: #0d9488; }

/* ---------- learning path ---------- */
.path { max-width: 720px; margin: 0 auto; }
.chapter {
  display: grid; grid-template-columns: auto 1fr; gap: 4px 14px; align-items: center;
  margin: 36px 0 18px; padding: 16px 18px; border-radius: 16px; background: var(--accent); color: #fff;
}
.chapter h2 { margin: 0; font-size: 18px; }
.chapter p { margin: 0; color: rgba(255, 255, 255, .85); font-size: 13px; }
.chapter-num {
  width: 40px; height: 40px; border-radius: 12px; background: rgba(255, 255, 255, .2);
  display: grid; place-items: center; font-weight: 800; font-size: 18px;
}
.chapter-bar { grid-column: 1 / -1; height: 6px; border-radius: 3px; background: rgba(255, 255, 255, .25); overflow: hidden; margin-top: 8px; }
.chapter-bar i { display: block; height: 100%; background: #fff; border-radius: 3px; }
:root[data-theme="dark"] .chapter { color: #0e1119; }
:root[data-theme="dark"] .chapter p { color: rgba(14, 17, 25, .75); }
:root[data-theme="dark"] .chapter-num, :root[data-theme="dark"] .chapter-bar { background: rgba(14, 17, 25, .15); }
:root[data-theme="dark"] .chapter-bar i { background: #0e1119; }

.trail { display: flex; flex-direction: column; align-items: center; gap: 6px; position: relative; padding: 4px 0; }
.trail::before {
  content: ""; position: absolute; top: 0; bottom: 0; left: 50%; width: 3px; margin-left: -1.5px;
  background: repeating-linear-gradient(var(--border) 0 8px, transparent 8px 14px);
}
.node {
  position: relative; display: flex; flex-direction: column; align-items: center; gap: 6px;
  transform: translateX(var(--x)); text-decoration: none; color: var(--fg); width: 220px; padding: 6px 0;
}
.dot {
  width: 58px; height: 58px; border-radius: 50%; display: grid; place-items: center;
  font-weight: 800; font-size: 18px; background: var(--surface); border: 3px solid var(--border);
  box-shadow: 0 4px 0 var(--border); transition: transform .15s;
}
.node:hover .dot { transform: translateY(-3px); }
.label {
  text-align: center; font-size: 13px; line-height: 1.35; background: var(--bg); padding: 2px 6px; border-radius: 6px;
}
.label small { display: block; color: var(--good); font-weight: 600; }
.badge {
  font-style: normal; font-size: 10px; text-transform: uppercase; letter-spacing: .05em; font-weight: 700;
  background: var(--accent-soft); color: var(--accent); padding: 1px 6px; border-radius: 999px; white-space: nowrap;
}
.node.done .dot { background: var(--good); border-color: var(--good); color: #fff; box-shadow: 0 4px 0 color-mix(in srgb, var(--good) 60%, #000); }
.node.started .dot { border-color: var(--accent); color: var(--accent); }
.node.next .dot {
  background: var(--accent); border-color: var(--accent); color: #fff;
  box-shadow: 0 4px 0 color-mix(in srgb, var(--accent) 60%, #000); animation: pulse 2s infinite;
}
.node.next .label { font-weight: 700; }
.bubble {
  position: absolute; top: -18px; background: var(--fg); color: var(--bg); font-size: 11px; font-weight: 700;
  padding: 3px 9px; border-radius: 999px; animation: bob 1.6s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { outline: 0 solid color-mix(in srgb, var(--accent) 40%, transparent); } 50% { outline: 10px solid transparent; } }
@keyframes bob { 50% { transform: translateY(-4px); } }
.finish { text-align: center; font-size: 20px; font-weight: 700; margin: 30px 0; }

/* ---------- lesson player ---------- */
.player-head { display: flex; align-items: center; gap: 14px; margin-bottom: 14px; }
.back { text-decoration: none; font-weight: 600; white-space: nowrap; }
.ph-title { flex: 1; min-width: 0; }
.ph-title small { color: var(--muted); font-size: 12px; }
.ph-title h1 { margin: 0; font-size: clamp(18px, 3vw, 24px); line-height: 1.25; }

.steps-bar { display: flex; gap: 4px; margin-bottom: 20px; }
.steps-bar button { flex: 1; border: 0; background: none; padding: 6px 0; cursor: pointer; }
.steps-bar i { display: block; height: 6px; border-radius: 3px; background: var(--border); transition: background .3s; }
.steps-bar .past i { background: color-mix(in srgb, var(--accent) 55%, var(--border)); }
.steps-bar .now i { background: var(--accent); }

.player-body { display: grid; grid-template-columns: 220px 1fr; gap: 24px; align-items: start; }
.outline { list-style: none; margin: 0; padding: 0; position: sticky; top: 72px; }
.outline button {
  display: flex; gap: 10px; width: 100%; text-align: left; border: 0; background: none; padding: 7px 8px;
  border-radius: 8px; cursor: pointer; font-size: 13px; color: var(--muted); line-height: 1.35;
}
.outline button span {
  flex-shrink: 0; width: 22px; height: 22px; border-radius: 50%; display: grid; place-items: center;
  font-size: 11px; font-weight: 700; background: var(--code-bg);
}
.outline button:hover { background: var(--code-bg); }
.outline .past { color: var(--fg); }
.outline .past span { background: var(--good); color: #fff; }
.outline .now { color: var(--accent); font-weight: 600; background: var(--accent-soft); }
.outline .now span { background: var(--accent); color: #fff; }

.card {
  position: relative; overflow: hidden;
  background: var(--surface); border-radius: 20px; padding: 28px 32px; box-shadow: var(--shadow);
  min-height: 320px; transition: opacity .25s, transform .25s;
}
.card.enter { opacity: 0; transform: translateY(8px); }
.card h2 { margin: 0 0 12px; font-size: 22px; line-height: 1.3; }
.controls { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-top: 16px; }

.prose { font-size: 16px; max-width: 70ch; }
.prose img { max-width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--border); }
.prose blockquote {
  margin: 16px 0; padding: 10px 16px; border-radius: 10px; background: var(--accent-soft); border: 0; color: var(--fg); font-size: 14px;
}
.prose blockquote p { margin: 0; }
.prose li { margin: 4px 0; }
.prose em { color: var(--muted); }
.table-wrap { overflow-x: auto; margin: 16px 0; }
.prose table { border-collapse: collapse; width: 100%; font-size: 14px; }
.prose th, .prose td { border: 1px solid var(--border); padding: 7px 10px; text-align: left; vertical-align: top; }
.prose th { background: var(--code-bg); }

.roadmap { margin-top: 20px; padding: 16px 20px; border-radius: 14px; background: var(--bg); }
.roadmap h3 { margin: 0 0 6px; font-size: 14px; text-transform: uppercase; letter-spacing: .05em; color: var(--muted); }
.roadmap ol { margin: 0; padding-left: 22px; }
.roadmap li.hl { list-style: none; margin-left: -22px; font-weight: 600; }

.takeaways ul { list-style: none; padding: 0; }
.takeaways li {
  position: relative; padding: 12px 14px 12px 46px; margin: 8px 0; border: 1px solid var(--border); border-radius: 12px;
  cursor: pointer; transition: background .2s, border-color .2s; user-select: none;
}
.takeaways li::before {
  content: ""; position: absolute; left: 14px; top: 13px; width: 20px; height: 20px; border-radius: 6px; border: 2px solid var(--border);
}
.takeaways li:hover { border-color: var(--accent); }
.takeaways li.got { background: var(--good-soft); border-color: var(--good); }
.takeaways li.got::before { content: "✓"; background: var(--good); border-color: var(--good); color: #fff; font-size: 13px; display: grid; place-items: center; font-weight: 800; }

/* quiz */
.q { font-size: 20px; }
.opts { display: grid; gap: 10px; margin: 18px 0; }
.opts button {
  display: flex; gap: 12px; align-items: center; text-align: left; padding: 12px 14px; border-radius: 12px;
  border: 2px solid var(--border); background: var(--surface); cursor: pointer; font-size: 15px;
  box-shadow: 0 3px 0 var(--border); transition: transform .08s;
}
.opts button span {
  flex-shrink: 0; width: 28px; height: 28px; border-radius: 8px; display: grid; place-items: center;
  background: var(--code-bg); font-weight: 700; font-size: 13px;
}
.opts button:hover:not(:disabled) { border-color: var(--accent); }
.opts button:active:not(:disabled) { transform: translateY(2px); box-shadow: 0 1px 0 var(--border); }
.opts button:disabled { opacity: 1; cursor: default; }
.opts button.right { border-color: var(--good); background: var(--good-soft); box-shadow: 0 3px 0 var(--good); }
.opts button.right span { background: var(--good); color: #fff; }
.opts button.wrong { border-color: var(--bad); background: var(--bad-soft); box-shadow: 0 3px 0 var(--bad); animation: shake .35s; }
.opts button.wrong span { background: var(--bad); color: #fff; }
@keyframes shake { 25% { transform: translateX(-5px); } 75% { transform: translateX(5px); } }
.explain { padding: 14px 16px; border-radius: 12px; display: flex; flex-wrap: wrap; gap: 10px 14px; align-items: center; }
.explain.ok { background: var(--good-soft); }
.explain.no { background: var(--bad-soft); }
.explain button { margin-left: auto; }
.quiz-result, .complete, .empty { text-align: center; padding: 20px 0; }
.quiz-result h2, .complete h2, .empty h2 { margin-top: 12px; }
.ring + h2 { margin-top: 12px; }
.trophy { font-size: 64px; animation: pop .6s cubic-bezier(.2, 1.6, .4, 1); }
@keyframes pop { from { transform: scale(0); } }
.up-next { margin-top: 18px; padding: 12px; border-radius: 12px; background: var(--bg); }

.confetti { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.confetti i {
  position: absolute; top: -10px; width: 8px; height: 14px; border-radius: 2px; opacity: 0;
  animation: fall 2.6s ease-in forwards;
}
@keyframes fall {
  0% { opacity: 1; transform: translate(0, 0) rotate(0); }
  100% { opacity: 0; transform: translate(var(--dx), 420px) rotate(var(--r)); }
}

/* ---------- widgets ---------- */
.widget h2 { margin-top: 0; }
.slider-label { display: block; margin: 18px 0; font-size: 15px; }
.slider-label input { display: block; width: 100%; margin-top: 8px; accent-color: var(--accent); }
.result-card { padding: 16px 18px; border-radius: 14px; background: var(--bg); border: 1px solid var(--border); }
.tag { display: inline-block; font-size: 12px; font-weight: 700; color: var(--accent); margin-bottom: 8px; }
.rec-row { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px dashed var(--border); }
.rec-row.hl b { color: var(--accent); font-size: 18px; }

.tl { position: relative; display: flex; gap: 3px; margin-top: 18px; }
.tl-rec {
  padding: 12px; border-radius: 10px; background: var(--code-bg); border: 2px solid transparent; transition: all .25s;
  display: flex; flex-direction: column; min-width: 0;
}
.tl-rec small { color: var(--muted); font-size: 11px; }
.tl-rec.active { border-color: var(--accent); background: var(--accent-soft); }
.tl-cursor {
  position: absolute; top: -8px; bottom: -8px; width: 3px; margin-left: -1.5px; background: var(--fg); border-radius: 2px; transition: left .1s;
}
.tl-cursor::before { content: "▼"; position: absolute; top: -16px; left: -5px; font-size: 11px; }
.tl-axis { display: flex; justify-content: space-between; font-size: 11px; color: var(--muted); margin-top: 10px; }

.sort-score { font-weight: 700; margin: 10px 0; }
.sort-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 10px; }
.sort-item { padding: 12px; border-radius: 12px; border: 2px solid var(--border); background: var(--surface); transition: all .25s; }
.sort-item small { display: block; font-size: 11px; color: var(--muted); text-transform: uppercase; letter-spacing: .05em; }
.sort-item b { display: block; margin: 2px 0 10px; }
.sort-btns { display: flex; gap: 6px; flex-wrap: wrap; font-size: 13px; font-weight: 600; }
.sort-btns button { flex: 1; border: 1px solid var(--border); background: var(--bg); padding: 6px; border-radius: 8px; cursor: pointer; font-size: 12px; white-space: nowrap; }
.sort-btns button:hover { border-color: var(--accent); color: var(--accent); }
.sort-item.ok { border-color: var(--good); background: var(--good-soft); }
.sort-item.no { border-color: var(--bad); background: var(--bad-soft); animation: shake .35s; }

.o2c { display: grid; gap: 10px; margin: 16px 0; }
.lane { padding: 10px 12px; border-radius: 14px; border-left: 5px solid var(--lc); background: color-mix(in srgb, var(--lc) 8%, var(--surface)); }
.lane.om, .o2c-info.om { --lc: var(--om); }
.lane.ar, .o2c-info.ar { --lc: var(--ar); }
.lane.gl, .o2c-info.gl { --lc: var(--gl); }
.lane h4 { margin: 0 0 8px; font-size: 12px; text-transform: uppercase; letter-spacing: .06em; color: var(--lc); }
.lane-stages { display: flex; flex-wrap: wrap; gap: 6px; }
.stage-btn {
  display: flex; align-items: center; gap: 6px; padding: 7px 10px; border-radius: 10px; cursor: pointer; font-size: 13px;
  border: 2px solid var(--border); background: var(--surface); transition: all .25s;
}
.stage-btn.past { border-color: color-mix(in srgb, var(--lc) 50%, var(--border)); opacity: .75; }
.stage-btn.now { border-color: var(--lc); background: var(--lc); color: #fff; transform: scale(1.06); box-shadow: 0 4px 14px color-mix(in srgb, var(--lc) 40%, transparent); }
.o2c-info { display: flex; gap: 14px; align-items: center; padding: 14px 16px; border-radius: 14px; background: var(--bg); min-height: 92px; border: 1px solid var(--border); }
.o2c-info.om, .o2c-info.ar, .o2c-info.gl { border-color: var(--lc); }
.o2c-info .big { font-size: 38px; }
.o2c-info small { color: var(--muted); font-size: 12px; }
.o2c-info b { display: block; font-size: 17px; }
.o2c-info p { margin: 2px 0 0; font-size: 14px; }
.o2c-ctrl { display: flex; gap: 8px; align-items: center; margin-top: 12px; }
.o2c-ctrl .ghost, .o2c-ctrl .primary { padding: 7px 14px; }
.o2c-progress { flex: 1; height: 6px; border-radius: 3px; background: var(--border); overflow: hidden; }
.o2c-progress i { display: block; height: 100%; width: 0; background: var(--accent); transition: width .4s; }

.gop-vis { display: flex; flex-wrap: wrap; gap: 6px; font-size: 26px; margin: 8px 0 14px; }
.unit { padding: 4px; border-radius: 8px; transition: all .25s; }
.unit.now { background: var(--good-soft); }
.unit.later { background: var(--code-bg); opacity: .45; filter: grayscale(1); }
.gop-out { padding: 14px 16px; border-radius: 12px; background: var(--accent-soft); }
.gop-list { padding-left: 22px; }
.gop-list li { padding: 4px 8px; border-radius: 8px; transition: all .25s; color: var(--muted); }
.gop-list li.on { background: var(--accent-soft); color: var(--fg); font-weight: 600; }

/* ---------- review ---------- */
.review, .search { max-width: 720px; margin: 0 auto; }
.review-head { display: flex; justify-content: space-between; align-items: end; gap: 16px; flex-wrap: wrap; margin-bottom: 20px; }
.review-head h1, .search h1 { margin: 0; }
.review-head p { margin: 4px 0 0; }
.seg { display: flex; padding: 4px; border-radius: 10px; background: var(--surface); box-shadow: var(--shadow); }
.seg button { border: 0; background: none; padding: 6px 12px; border-radius: 8px; cursor: pointer; font-size: 13px; }
.seg button.on { background: var(--accent); color: #fff; }
.flip { perspective: 1200px; height: 300px; cursor: pointer; outline: none; margin: 10px 0 18px; }
.flip-inner { position: relative; height: 100%; transition: transform .55s cubic-bezier(.3, 1.3, .5, 1); transform-style: preserve-3d; }
.flip.flipped .flip-inner { transform: rotateY(180deg); }
.face {
  position: absolute; inset: 0; backface-visibility: hidden; border-radius: 20px; padding: 28px;
  display: flex; flex-direction: column; justify-content: center; align-items: center; text-align: center;
  background: var(--surface); box-shadow: var(--shadow); border: 2px solid var(--border);
}
.flip:focus-visible .face { border-color: var(--accent); }
.face small { position: absolute; top: 16px; left: 20px; right: 20px; color: var(--muted); font-size: 12px; }
.face p { font-size: 22px; font-weight: 700; margin: 0; width: 100%; overflow-wrap: anywhere; }
.face.back { transform: rotateY(180deg); background: var(--accent-soft); }
.face.back p { font-size: 18px; font-weight: 500; }
.hint { position: absolute; bottom: 14px; font-size: 12px; color: var(--muted); }
.pips { position: absolute; bottom: 16px; display: flex; gap: 5px; }
.pips i { width: 18px; height: 6px; border-radius: 3px; background: var(--border); }
.pips i.on { background: var(--good); }
.grade { display: flex; gap: 12px; justify-content: center; }

/* ---------- search ---------- */
.search input {
  width: 100%; margin: 16px 0; padding: 14px 18px; font-size: 17px; border-radius: 14px;
  border: 2px solid var(--border); background: var(--surface); color: var(--fg); outline: none;
}
.search input:focus { border-color: var(--accent); }
.hit {
  display: block; padding: 14px 16px; margin: 8px 0; border-radius: 12px; background: var(--surface);
  box-shadow: var(--shadow); text-decoration: none; color: var(--fg); border: 1px solid transparent;
}
.hit:hover { border-color: var(--accent); }
.hit small { display: block; color: var(--muted); font-size: 12px; }
.hit span { display: block; font-size: 14px; color: var(--muted); margin-top: 4px; }
mark { background: color-mix(in srgb, var(--warn) 35%, transparent); color: inherit; border-radius: 3px; padding: 0 2px; }
.gl-h { margin-top: 36px; }
.glossary { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 10px; }
.glossary a {
  padding: 12px 14px; border-radius: 12px; background: var(--surface); box-shadow: var(--shadow);
  text-decoration: none; color: var(--fg); border: 1px solid transparent;
}
.glossary a:hover { border-color: var(--accent); }
.glossary b { display: block; font-size: 17px; color: var(--accent); }
.glossary span { font-size: 13px; color: var(--muted); }

/* ---------- responsive ---------- */
@media (max-width: 860px) {
  .player-body { grid-template-columns: 1fr; }
  .outline { display: none; }
}
@media (max-width: 600px) {
  .tabs a span, .pill-btn span { display: none; }
  .tabs { justify-content: flex-end; }
  .hero { padding: 20px; }
  .stats { width: 100%; }
  .stat { flex: 1; min-width: 0; }
  .card { padding: 20px 18px; border-radius: 16px; }
  .node { width: 180px; }
  .node { transform: translateX(calc(var(--x) * .6)); }
  .course-switch button { padding: 8px 10px; font-size: 14px; }
  .flip { height: 340px; }
  .face p { font-size: 19px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}