:root {
  color-scheme: dark;
  --bg: #081016;
  --bg-elevated: #0d171f;
  --bg-soft: #101d26;
  --bg-hover: #14232d;
  --panel: rgba(13, 23, 31, 0.92);
  --panel-solid: #0d171f;
  --text: #e9f1f4;
  --text-strong: #ffffff;
  --muted: #8fa5af;
  --muted-2: #617681;
  --line: #20333d;
  --line-strong: #31505d;
  --accent: #6ee7c7;
  --accent-strong: #2dd4a7;
  --accent-soft: rgba(110, 231, 199, 0.12);
  --accent-2: #f5bd63;
  --accent-2-soft: rgba(245, 189, 99, 0.12);
  --danger: #ff7b82;
  --danger-soft: rgba(255, 123, 130, 0.12);
  --info: #80c9ff;
  --info-soft: rgba(128, 201, 255, 0.12);
  --purple: #bd9eff;
  --purple-soft: rgba(189, 158, 255, 0.12);
  --shadow: 0 20px 65px rgba(0, 0, 0, 0.28);
  --sidebar-w: 286px;
  --toc-w: 244px;
  --topbar-h: 66px;
  --content-max: 920px;
  --radius-sm: 7px;
  --radius: 8px;
  --radius-lg: 8px;
  --mono: "SFMono-Regular", "Cascadia Code", "Roboto Mono", Consolas, monospace;
  --sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

html[data-theme="light"] {
  color-scheme: light;
  --bg: #f4f7f7;
  --bg-elevated: #ffffff;
  --bg-soft: #edf3f3;
  --bg-hover: #e5eeee;
  --panel: rgba(255, 255, 255, 0.94);
  --panel-solid: #ffffff;
  --text: #1d3038;
  --text-strong: #08181f;
  --muted: #607681;
  --muted-2: #8ca0a9;
  --line: #d4e0e3;
  --line-strong: #b8cdd2;
  --accent: #087f6a;
  --accent-strong: #056451;
  --accent-soft: rgba(8, 127, 106, 0.09);
  --accent-2: #a46400;
  --accent-2-soft: rgba(164, 100, 0, 0.09);
  --danger: #bd3541;
  --danger-soft: rgba(189, 53, 65, 0.09);
  --info: #176e9e;
  --info-soft: rgba(23, 110, 158, 0.09);
  --purple: #6a4fb4;
  --purple-soft: rgba(106, 79, 180, 0.09);
  --shadow: 0 20px 60px rgba(29, 53, 62, 0.12);
}

* { box-sizing: border-box; letter-spacing: 0 !important; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 15.5px;
  line-height: 1.62;
  -webkit-font-smoothing: antialiased;
}

button, input, textarea, select { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--text-strong); }

::selection { background: var(--accent); color: #062018; }

.skip-link {
  position: fixed;
  left: 12px;
  top: -100px;
  z-index: 200;
  padding: 9px 13px;
  background: var(--accent);
  color: #05241b;
  border-radius: var(--radius-sm);
  font-weight: 700;
}
.skip-link:focus { top: 10px; }

#app-shell {
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr) var(--toc-w);
  grid-template-rows: var(--topbar-h) minmax(calc(100vh - var(--topbar-h)), auto);
  grid-template-areas:
    "topbar topbar topbar"
    "sidebar main toc";
}

.topbar {
  grid-area: topbar;
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--topbar-h);
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr) auto;
  align-items: center;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(18px) saturate(120%);
}

.topbar-left { display: flex; align-items: center; height: 100%; padding: 0 20px; }
.brand { display: inline-flex; align-items: center; gap: 11px; color: var(--text-strong); }
.brand:hover { color: var(--text-strong); }
.brand-mark { width: 28px; height: 28px; position: relative; display: inline-block; transform: rotate(-3deg); }
.brand-mark span { position: absolute; left: 3px; right: 3px; height: 5px; border-radius: 999px; background: var(--accent); box-shadow: 0 0 16px rgba(110, 231, 199, 0.25); }
.brand-mark span:nth-child(1) { top: 3px; width: 14px; }
.brand-mark span:nth-child(2) { top: 11px; width: 22px; }
.brand-mark span:nth-child(3) { top: 19px; width: 10px; left: 15px; }
.brand-copy { display: grid; line-height: 1.05; letter-spacing: 0; }
.brand-copy strong { font-size: 13px; }
.brand-copy small { color: var(--muted); font: 9px/1.4 var(--mono); letter-spacing: 0; }

.top-nav { display: flex; height: 100%; align-items: center; gap: 2px; padding-left: 26px; }
.top-nav a { position: relative; display: grid; place-items: center; height: 100%; padding: 0 15px; color: var(--muted); font-weight: 650; font-size: 13.5px; }
.top-nav a:hover { color: var(--text-strong); }
.top-nav a.active { color: var(--text-strong); }
.top-nav a.active::after { content: ""; position: absolute; left: 14px; right: 14px; bottom: -1px; height: 2px; background: var(--accent); }

.topbar-actions { display: flex; align-items: center; gap: 7px; padding: 0 18px; }
.icon-button, .search-trigger {
  border: 1px solid var(--line);
  background: var(--bg-elevated);
  color: var(--muted);
  border-radius: 9px;
  min-height: 36px;
  cursor: pointer;
  transition: border-color .18s ease, color .18s ease, background .18s ease, transform .18s ease;
}
.icon-button:hover, .search-trigger:hover { border-color: var(--line-strong); color: var(--text-strong); background: var(--bg-hover); }
.icon-button:active, .search-trigger:active { transform: translateY(1px); }
.icon-button { width: 36px; display: grid; place-items: center; padding: 0; }
.icon-button svg, .sidebar-action svg, .search-trigger svg { width: 17px; height: 17px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }
.site-home { width: auto; display: flex; align-items: center; gap: 6px; padding: 0 10px; font-size: 12.5px; font-weight: 650; }
.search-trigger { display: flex; align-items: center; gap: 7px; padding: 0 9px; min-width: 178px; }
.search-trigger span { font-size: 13px; flex: 1; text-align: left; }
kbd { font: 10.5px/1 var(--mono); color: var(--muted); background: var(--bg-soft); border: 1px solid var(--line); border-bottom-color: var(--line-strong); border-radius: 5px; padding: 4px 5px; }
.theme-icon-moon { display: none; }
html[data-theme="light"] .theme-icon-sun { display: none; }
html[data-theme="light"] .theme-icon-moon { display: block; }

.sidebar {
  grid-area: sidebar;
  position: sticky;
  top: var(--topbar-h);
  height: calc(100vh - var(--topbar-h));
  overflow-y: auto;
  border-right: 1px solid var(--line);
  background: var(--panel);
  padding: 20px 13px 16px;
  scrollbar-width: thin;
  scrollbar-color: var(--line-strong) transparent;
}
.sidebar-progress { display: flex; align-items: center; gap: 12px; padding: 5px 8px 20px; border-bottom: 1px solid var(--line); margin-bottom: 15px; }
.sidebar-progress > div:last-child { display: grid; min-width: 0; }
.sidebar-progress strong { color: var(--text-strong); font-size: 12.5px; }
.sidebar-progress span:not(.progress-ring span) { color: var(--muted); font-size: 11px; }
.progress-ring {
  --progress: 0;
  width: 44px; height: 44px; flex: 0 0 auto;
  border-radius: 50%;
  display: grid; place-items: center;
  background: conic-gradient(var(--accent) calc(var(--progress) * 1%), var(--line) 0);
  position: relative;
}
.progress-ring::after { content: ""; position: absolute; inset: 4px; border-radius: inherit; background: var(--panel-solid); }
.progress-ring span { position: relative; z-index: 1; color: var(--text-strong); font: 700 9px/1 var(--mono); }
.sidebar-section-label { color: var(--muted-2); text-transform: uppercase; letter-spacing: 0; font: 10px/1 var(--mono); padding: 0 10px 9px; }
.chapter-nav { display: grid; gap: 2px; }
.chapter-link {
  display: grid;
  grid-template-columns: 25px minmax(0, 1fr) auto;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 7px 9px;
  border-radius: 8px;
  color: var(--muted);
  border: 1px solid transparent;
}
.chapter-link:hover { background: var(--bg-hover); color: var(--text); }
.chapter-link.active { color: var(--text-strong); background: var(--accent-soft); border-color: color-mix(in srgb, var(--accent) 24%, transparent); }
.chapter-link .chapter-id { font: 11px/1 var(--mono); color: var(--muted-2); }
.chapter-link.active .chapter-id { color: var(--accent); }
.chapter-link .chapter-name { font-size: 12.5px; font-weight: 610; line-height: 1.25; }
.chapter-status { width: 15px; height: 15px; border: 1px solid var(--line-strong); border-radius: 50%; display: grid; place-items: center; }
.chapter-status.done { background: var(--accent); border-color: var(--accent); color: #05241b; }
.chapter-status.done::after { content: "✓"; font: 800 9px/1 var(--sans); }
.chapter-status.partial { border-color: var(--accent); background: var(--accent-soft); }
.sidebar-footer { display: grid; gap: 4px; margin-top: 18px; padding-top: 14px; border-top: 1px solid var(--line); }
.sidebar-action { display: flex; align-items: center; gap: 9px; padding: 9px 10px; border: 0; border-radius: 8px; color: var(--muted); background: transparent; cursor: pointer; text-align: left; font-size: 12px; }
.sidebar-action:hover { color: var(--text-strong); background: var(--bg-hover); }
.sidebar-action svg { width: 15px; height: 15px; }
.sidebar-action.subtle:hover { color: var(--danger); }
.sidebar-socials { display: flex; flex-wrap: wrap; gap: 6px 14px; margin-top: 8px; padding: 13px 10px 2px; border-top: 1px solid var(--line); }
.sidebar-socials a { color: var(--muted); font: 11px/1.4 var(--mono); }
.sidebar-socials a:hover { color: var(--accent); }

.main-content {
  grid-area: main;
  min-width: 0;
  padding: 54px clamp(28px, 5vw, 74px) 100px;
}
.main-content:focus { outline: none; }
.content-wrap { max-width: var(--content-max); margin: 0 auto; }
.page-toc {
  grid-area: toc;
  position: sticky;
  top: var(--topbar-h);
  height: calc(100vh - var(--topbar-h));
  overflow-y: auto;
  border-left: 1px solid var(--line);
  padding: 30px 22px;
  color: var(--muted);
}
.toc-title { text-transform: uppercase; letter-spacing: 0; font: 10px/1 var(--mono); color: var(--muted-2); margin-bottom: 14px; }
.toc-list { display: grid; gap: 2px; border-left: 1px solid var(--line); }
.toc-link { display: block; color: var(--muted); font-size: 11.5px; line-height: 1.35; padding: 6px 0 6px 13px; margin-left: -1px; border-left: 1px solid transparent; }
.toc-link:hover { color: var(--text-strong); }
.toc-link.active { color: var(--accent); border-left-color: var(--accent); }
.toc-link.level-3 { padding-left: 24px; font-size: 11px; }
.toc-progress-card { margin-top: 25px; padding: 13px; border: 1px solid var(--line); border-radius: 10px; background: var(--bg-elevated); }
.toc-progress-card strong { display: block; color: var(--text-strong); font-size: 11.5px; margin-bottom: 5px; }
.toc-progress-card p { margin: 0; font-size: 10.5px; line-height: 1.45; }

.eyebrow { display: inline-flex; align-items: center; gap: 8px; color: var(--accent); text-transform: uppercase; letter-spacing: 0; font: 700 10.5px/1.3 var(--mono); margin-bottom: 14px; }
.eyebrow::before { content: ""; width: 18px; height: 1px; background: currentColor; }
.page-title, .lesson-title { margin: 0; color: var(--text-strong); line-height: 1.08; }
.page-title { font-size: 56px; max-width: 900px; }
.lesson-title { font-size: 50px; max-width: 850px; }
.page-lede, .lesson-lede { color: var(--muted); font-size: 20px; line-height: 1.55; max-width: 760px; margin: 22px 0 0; }

.hero { position: relative; padding: 20px 0 45px; }
.hero::before { display: none; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 30px; }
.button {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  min-height: 42px; padding: 0 16px;
  border: 1px solid var(--line-strong); border-radius: 9px;
  background: var(--bg-elevated); color: var(--text-strong);
  font-weight: 700; font-size: 13px; cursor: pointer;
  transition: transform .16s ease, background .16s ease, border-color .16s ease;
}
.button:hover { color: var(--text-strong); border-color: var(--accent); background: var(--bg-hover); }
.button:active { transform: translateY(1px); }
.button.primary { color: #05241b; border-color: var(--accent); background: var(--accent); }
.button.primary:hover { background: var(--accent-strong); border-color: var(--accent-strong); color: #fff; }
.button.danger { color: var(--danger); }
.button.small { min-height: 34px; padding: 0 11px; font-size: 11.5px; }
.button svg { width: 16px; height: 16px; fill: none; stroke: currentColor; stroke-width: 1.8; stroke-linecap: round; stroke-linejoin: round; }

.stat-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 10px; margin: 30px 0 8px; }
.stat-card { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); padding: 14px 16px; }
.stat-card span { display: block; color: var(--muted-2); font: 10px/1.2 var(--mono); text-transform: uppercase; letter-spacing: 0; }
.stat-card strong { display: block; color: var(--text-strong); font-size: 20px; letter-spacing: 0; margin-top: 6px; }

.section { margin-top: 66px; scroll-margin-top: calc(var(--topbar-h) + 24px); }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 18px; margin-bottom: 22px; }
.section-heading h2, .prose h2 { color: var(--text-strong); font-size: 28px; line-height: 1.2; letter-spacing: 0; margin: 0; }
.section-heading p { color: var(--muted); max-width: 570px; margin: 6px 0 0; }
.section-kicker { color: var(--muted-2); text-transform: uppercase; letter-spacing: 0; font: 10px/1 var(--mono); margin-bottom: 8px; }

.path-panel { display: grid; grid-template-columns: minmax(0, 1.15fr) minmax(280px, .85fr); gap: 14px; }
.path-visual, .next-panel { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius-lg); padding: 23px; min-height: 250px; }
.path-visual { position: relative; overflow: hidden; }
.path-visual::after { content: ""; position: absolute; width: 170px; height: 170px; border: 1px solid var(--line); border-radius: 50%; right: -70px; top: -60px; box-shadow: 0 0 0 30px rgba(110,231,199,.025), 0 0 0 60px rgba(110,231,199,.02); }
.path-visual h3, .next-panel h3 { color: var(--text-strong); margin: 0 0 17px; font-size: 17px; }
.path-flow { display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); align-items: center; gap: 6px; position: relative; z-index: 1; }
.path-node { position: relative; display: grid; place-items: center; text-align: center; min-height: 91px; border: 1px solid var(--line); background: var(--bg-soft); border-radius: 10px; padding: 8px; color: var(--muted); font: 10px/1.35 var(--mono); }
.path-node strong { color: var(--text-strong); font: 700 11px/1.3 var(--sans); margin-bottom: 4px; }
.path-node:not(:last-child)::after { content: "→"; position: absolute; right: -11px; color: var(--muted-2); }
.next-panel { display: flex; flex-direction: column; }
.next-panel .next-label { color: var(--accent); font: 10px/1 var(--mono); letter-spacing: 0; text-transform: uppercase; }
.next-panel .next-title { color: var(--text-strong); font-size: 21px; line-height: 1.25; letter-spacing: 0; margin: 9px 0; }
.next-panel p { color: var(--muted); font-size: 13px; margin: 0 0 18px; }
.next-panel .button { margin-top: auto; align-self: flex-start; }

.module-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.module-card { position: relative; display: flex; flex-direction: column; border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); padding: 18px; color: var(--text); min-height: 200px; transition: transform .16s ease, border-color .16s ease, background .16s ease; overflow: hidden; }
.module-card::before { content: ""; position: absolute; inset: 0 auto 0 0; width: 2px; background: var(--track-color, var(--accent)); opacity: .85; }
.module-card:hover { transform: translateY(-2px); border-color: var(--line-strong); background: var(--bg-hover); color: var(--text); }
.module-card.completed { border-color: color-mix(in srgb, var(--accent) 33%, var(--line)); }
.module-card-head { display: flex; justify-content: space-between; gap: 14px; align-items: flex-start; }
.module-number { color: var(--track-color, var(--accent)); font: 700 11px/1 var(--mono); letter-spacing: 0; }
.module-check { width: 20px; height: 20px; border: 1px solid var(--line-strong); border-radius: 50%; display: grid; place-items: center; color: #05241b; font-size: 11px; }
.module-card.completed .module-check { background: var(--accent); border-color: var(--accent); }
.module-card.completed .module-check::after { content: "✓"; font-weight: 900; }
.module-card h3 { color: var(--text-strong); font-size: 17px; line-height: 1.28; letter-spacing: 0; margin: 15px 0 7px; }
.module-card p { color: var(--muted); font-size: 12.5px; line-height: 1.5; margin: 0 0 16px; }
.module-meta { display: flex; flex-wrap: wrap; gap: 6px; margin-top: auto; }
.badge { display: inline-flex; align-items: center; gap: 5px; border: 1px solid var(--line); border-radius: 999px; padding: 5px 8px; color: var(--muted); font: 10px/1 var(--mono); background: color-mix(in srgb, var(--bg-soft) 84%, transparent); }
.badge.accent { color: var(--accent); border-color: color-mix(in srgb, var(--accent) 30%, var(--line)); background: var(--accent-soft); }
.badge.warning { color: var(--accent-2); border-color: color-mix(in srgb, var(--accent-2) 30%, var(--line)); background: var(--accent-2-soft); }
.badge.info { color: var(--info); border-color: color-mix(in srgb, var(--info) 30%, var(--line)); background: var(--info-soft); }
.badge.purple { color: var(--purple); border-color: color-mix(in srgb, var(--purple) 30%, var(--line)); background: var(--purple-soft); }

.principles-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; }
.principle { border-top: 1px solid var(--line-strong); padding: 17px 3px 0; }
.principle .principle-num { color: var(--accent); font: 10px/1 var(--mono); }
.principle h3 { color: var(--text-strong); font-size: 14px; margin: 10px 0 7px; }
.principle p { color: var(--muted); font-size: 12px; margin: 0; }

.course-intro { padding: 18px 0 28px; border-bottom: 1px solid var(--line); }
.course-credit { margin: 16px 0 0; color: var(--text); font: 12px/1.4 var(--mono); }
.course-facts { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); margin: 34px 0 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.course-facts div { padding: 13px 16px; border-right: 1px solid var(--line); }
.course-facts div:first-child { padding-left: 0; }
.course-facts div:last-child { border-right: 0; }
.course-facts dt { color: var(--muted-2); font: 10px/1.3 var(--mono); text-transform: uppercase; }
.course-facts dd { margin: 5px 0 0; color: var(--text-strong); font-size: 13px; font-weight: 700; }
.orientation-definition { margin-bottom: 20px; padding: 0 0 18px 18px; border-left: 2px solid var(--accent); border-bottom: 1px solid var(--line); }
.orientation-definition h3 { margin: 0 0 7px; color: var(--text-strong); font-size: 17px; }
.orientation-definition p { max-width: 780px; margin: 0; color: var(--muted); }
.orientation-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); border-top: 1px solid var(--line); }
.orientation-block { min-width: 0; padding: 22px 24px 24px 0; border-bottom: 1px solid var(--line); }
.orientation-block:nth-child(even) { padding-right: 0; padding-left: 24px; border-left: 1px solid var(--line); }
.orientation-label { display: block; margin-bottom: 8px; color: var(--accent); font: 10px/1.3 var(--mono); text-transform: uppercase; }
.orientation-block h3 { margin: 0 0 10px; color: var(--text-strong); font-size: 16px; line-height: 1.35; }
.orientation-block p { margin: 8px 0 0; color: var(--muted); font-size: 13px; }
.tool-boundaries { margin: 0; }
.tool-boundaries div { display: grid; grid-template-columns: 76px minmax(0, 1fr); gap: 12px; padding: 7px 0; border-top: 1px solid var(--line); }
.tool-boundaries div:first-child { border-top: 0; }
.tool-boundaries dt { color: var(--text-strong); font: 700 11px/1.45 var(--mono); }
.tool-boundaries dd { margin: 0; color: var(--muted); font-size: 12.5px; line-height: 1.45; }
.outcome-list { margin: 0; padding-left: 19px; color: var(--muted); }
.outcome-list li { margin: 8px 0; font-size: 12.5px; line-height: 1.5; }
.outcome-list strong { color: var(--text-strong); }
.orientation-scope { margin: 16px 0 0; color: var(--muted); font-size: 13px; }
.orientation-scope strong { color: var(--text-strong); }
.background-grid { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.background-grid > div { padding: 20px 24px 20px 0; }
.background-grid > div + div { padding-left: 24px; border-left: 1px solid var(--line); }
.background-grid h3 { margin: 0 0 12px; color: var(--text-strong); font-size: 14px; }
.plain-list { margin: 0; padding-left: 18px; color: var(--muted); }
.plain-list li { margin: 6px 0; }
.hardware-note { margin: 15px 0 0; color: var(--muted); font-size: 13px; }
.hardware-note strong { color: var(--text-strong); }
.method-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--line); }
.method-list li { display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 14px; padding: 16px 0; border-bottom: 1px solid var(--line); }
.method-list li > span { color: var(--accent); font: 700 11px/1.5 var(--mono); }
.method-list strong { display: block; color: var(--text-strong); font-size: 14px; }
.method-list p { margin: 3px 0 0; color: var(--muted); font-size: 13px; }
.continue-strip { display: flex; align-items: center; justify-content: space-between; gap: 24px; margin-top: 24px; padding: 18px 0; border-top: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong); }
.continue-strip > div { min-width: 0; }
.continue-strip span { display: block; color: var(--accent); font: 10px/1.3 var(--mono); text-transform: uppercase; }
.continue-strip strong { display: block; margin-top: 6px; color: var(--text-strong); font-size: 17px; }
.continue-strip p { margin: 4px 0 0; color: var(--muted); font-size: 12.5px; }
.continue-strip .button { flex: 0 0 auto; }
.module-list { border-top: 1px solid var(--line); }
.module-row { display: grid; grid-template-columns: 46px minmax(0, 1fr) 130px 42px; align-items: center; gap: 16px; min-height: 92px; padding: 14px 0; border-bottom: 1px solid var(--line); color: var(--text); }
.module-row:hover { color: var(--text); background: var(--bg-soft); }
.module-index { color: var(--track-color, var(--accent)); font: 700 12px/1 var(--mono); }
.module-copy { min-width: 0; }
.module-copy strong { display: block; color: var(--text-strong); font-size: 15px; line-height: 1.3; }
.module-copy small { display: block; margin-top: 5px; color: var(--muted); font-size: 12.5px; line-height: 1.45; }
.module-details { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; color: var(--muted-2); font: 10px/1.3 var(--mono); }
.module-state { justify-self: end; color: var(--accent); font: 700 11px/1 var(--mono); }
.module-row.completed .module-copy strong { color: var(--accent); }

:where(.toc-progress-card, .objective, .code-block, .reading-card, .search-dialog-shell, .search-result, .resource-card, .check-item, .toast) { border-radius: 8px; }

.lesson-header { position: relative; padding-bottom: 32px; border-bottom: 1px solid var(--line); }
.lesson-meta { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 25px; }
.lesson-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }
.lesson-progress-bar { height: 4px; background: var(--line); border-radius: 999px; overflow: hidden; margin-top: 29px; }
.lesson-progress-bar span { display: block; height: 100%; width: var(--lesson-progress, 0%); background: var(--accent); border-radius: inherit; transition: width .3s ease; }

.callout { display: grid; grid-template-columns: 24px minmax(0, 1fr); gap: 12px; border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); padding: 16px 17px; margin: 20px 0; }
.callout-icon { width: 24px; height: 24px; display: grid; place-items: center; border-radius: 7px; background: var(--accent-soft); color: var(--accent); font: 800 12px/1 var(--mono); }
.callout.warning { border-color: color-mix(in srgb, var(--accent-2) 30%, var(--line)); background: var(--accent-2-soft); }
.callout.warning .callout-icon { background: rgba(245,189,99,.18); color: var(--accent-2); }
.callout.danger { border-color: color-mix(in srgb, var(--danger) 30%, var(--line)); background: var(--danger-soft); }
.callout.danger .callout-icon { background: rgba(255,123,130,.17); color: var(--danger); }
.callout.info { border-color: color-mix(in srgb, var(--info) 30%, var(--line)); background: var(--info-soft); }
.callout.info .callout-icon { background: rgba(128,201,255,.17); color: var(--info); }
.callout strong { display: block; color: var(--text-strong); font-size: 13px; margin-bottom: 3px; }
.callout p { color: var(--muted); font-size: 12.5px; margin: 0; }
.callout code { font-size: .92em; }

.objectives { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 8px; counter-reset: objective; }
.objective { counter-increment: objective; position: relative; min-height: 74px; border: 1px solid var(--line); border-radius: 10px; background: var(--bg-elevated); padding: 13px 13px 13px 43px; color: var(--text); font-size: 12.5px; }
.objective::before { content: counter(objective, decimal-leading-zero); position: absolute; left: 13px; top: 15px; color: var(--accent); font: 700 10px/1 var(--mono); }

.prose { color: var(--text); }
.prose h2 { margin-top: 58px; margin-bottom: 18px; scroll-margin-top: calc(var(--topbar-h) + 24px); }
.prose h3 { color: var(--text-strong); font-size: 19px; letter-spacing: 0; margin: 35px 0 12px; scroll-margin-top: calc(var(--topbar-h) + 24px); }
.prose p { margin: 13px 0; }
.prose ul, .prose ol { padding-left: 22px; }
.prose li { margin: 6px 0; }
.prose strong { color: var(--text-strong); }
.prose code:not(pre code) { font: .88em/1.4 var(--mono); color: var(--accent); background: var(--accent-soft); border: 1px solid color-mix(in srgb, var(--accent) 15%, transparent); border-radius: 5px; padding: 1px 5px; }
.prose > pre, .prose section > pre {
  margin: 18px 0;
  padding: 16px;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: var(--bg-soft);
  color: var(--text);
  font: 12px/1.62 var(--mono);
  tab-size: 2;
}
.prose blockquote { margin: 20px 0; padding: 3px 0 3px 17px; border-left: 2px solid var(--accent); color: var(--muted); }
.prose table { width: 100%; border-collapse: collapse; font-size: 12.5px; margin: 20px 0; }
.prose th { color: var(--text-strong); background: var(--bg-soft); text-align: left; font-size: 11px; }
.prose th, .prose td { padding: 10px 12px; border: 1px solid var(--line); vertical-align: top; }

.code-block { position: relative; margin: 18px 0; border: 1px solid var(--line); border-radius: 11px; overflow: hidden; background: #071015; }
html[data-theme="light"] .code-block { background: #101d22; }
.code-head { display: flex; justify-content: space-between; align-items: center; min-height: 34px; padding: 0 9px 0 13px; background: rgba(255,255,255,.025); border-bottom: 1px solid rgba(255,255,255,.08); color: #91a6af; font: 10px/1 var(--mono); }
.copy-code { border: 0; background: transparent; color: #91a6af; cursor: pointer; padding: 6px 7px; border-radius: 5px; font: 10px/1 var(--mono); }
.copy-code:hover { color: #fff; background: rgba(255,255,255,.07); }
.code-block pre { margin: 0; padding: 16px; overflow-x: auto; color: #d7e7eb; font: 12px/1.62 var(--mono); tab-size: 2; }
.code-block .kw { color: #c6a6ff; }
.code-block .fn { color: #79d9ff; }
.code-block .str { color: #a7e887; }
.code-block .cm { color: #627984; }

.reading-list { display: grid; gap: 8px; }
.reading-card { display: grid; grid-template-columns: 36px minmax(0, 1fr) auto; gap: 12px; align-items: center; border: 1px solid var(--line); background: var(--bg-elevated); border-radius: 10px; padding: 12px 13px; color: var(--text); }
.reading-card:hover { color: var(--text); border-color: var(--line-strong); background: var(--bg-hover); }
.reading-icon { width: 36px; height: 36px; display: grid; place-items: center; border-radius: 8px; background: var(--accent-soft); color: var(--accent); font: 700 10px/1 var(--mono); }
.reading-card strong { display: block; color: var(--text-strong); font-size: 12.5px; line-height: 1.3; }
.reading-card small { display: block; color: var(--muted); margin-top: 3px; line-height: 1.35; }
.reading-arrow { color: var(--muted-2); font-size: 18px; }

.lab-list { display: grid; gap: 12px; }
.lab-card { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); overflow: hidden; }
.lab-card.completed { border-color: color-mix(in srgb, var(--accent) 36%, var(--line)); }
.lab-head { display: grid; grid-template-columns: 32px minmax(0, 1fr) auto; gap: 11px; align-items: start; padding: 16px 17px; cursor: pointer; }
.lab-head:hover { background: var(--bg-hover); }
.lab-index { color: var(--accent); font: 700 11px/1.2 var(--mono); padding-top: 3px; }
.lab-title { color: var(--text-strong); font-size: 14px; font-weight: 720; line-height: 1.35; }
.lab-subtitle { color: var(--muted); font-size: 11.5px; margin-top: 4px; }
.lab-chevron { width: 22px; height: 22px; border-radius: 6px; display: grid; place-items: center; color: var(--muted); transition: transform .18s ease; }
.lab-card.open .lab-chevron { transform: rotate(180deg); }
.lab-body { display: none; border-top: 1px solid var(--line); padding: 17px; }
.lab-card.open .lab-body { display: block; }
.lab-task-list { display: grid; gap: 7px; margin: 14px 0; }
.task-check { display: grid; grid-template-columns: 21px minmax(0, 1fr); gap: 9px; align-items: start; cursor: pointer; color: var(--text); font-size: 12.5px; }
.task-check input { position: absolute; opacity: 0; pointer-events: none; }
.task-box { width: 17px; height: 17px; border: 1px solid var(--line-strong); border-radius: 5px; margin-top: 2px; display: grid; place-items: center; transition: .15s ease; }
.task-check input:checked + .task-box { background: var(--accent); border-color: var(--accent); color: #05241b; }
.task-check input:checked + .task-box::after { content: "✓"; font-size: 10px; font-weight: 900; }
.task-check input:checked ~ span:last-child { color: var(--muted); text-decoration: line-through; text-decoration-color: var(--muted-2); }
.acceptance { margin-top: 17px; border-top: 1px solid var(--line); padding-top: 14px; }
.acceptance strong, .deliverable strong { color: var(--text-strong); font-size: 11px; text-transform: uppercase; letter-spacing: 0; font-family: var(--mono); }
.acceptance ul { margin-bottom: 0; }
.deliverable { padding: 11px 12px; border-radius: 8px; background: var(--accent-soft); color: var(--muted); font-size: 12px; }

.exercise-card { border: 1px solid var(--line); border-radius: var(--radius); background: var(--bg-elevated); overflow: hidden; margin: 16px 0; }
.exercise-head { display: flex; justify-content: space-between; gap: 12px; align-items: flex-start; padding: 15px 16px; border-bottom: 1px solid var(--line); }
.exercise-head h3 { margin: 0; font-size: 14px; }
.exercise-meta { display: flex; flex-wrap: wrap; gap: 5px; }
.exercise-body { padding: 16px; }
.disclosure { margin-top: 10px; border: 1px solid var(--line); border-radius: 8px; overflow: hidden; }
.disclosure summary { cursor: pointer; padding: 9px 12px; color: var(--muted); font-size: 11.5px; background: var(--bg-soft); user-select: none; }
.disclosure summary:hover { color: var(--text-strong); }
.disclosure > div { padding: 12px; border-top: 1px solid var(--line); color: var(--muted); font-size: 12.5px; }

.quiz { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); padding: 18px; }
.quiz-question { color: var(--text-strong); font-size: 15px; font-weight: 680; margin-bottom: 14px; }
.quiz-options { display: grid; gap: 7px; }
.quiz-option { display: grid; grid-template-columns: 25px minmax(0, 1fr); align-items: center; gap: 8px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg-soft); padding: 10px 11px; cursor: pointer; color: var(--text); font-size: 12.5px; text-align: left; }
.quiz-option:hover { border-color: var(--line-strong); background: var(--bg-hover); }
.quiz-option.correct { border-color: var(--accent); background: var(--accent-soft); }
.quiz-option.incorrect { border-color: var(--danger); background: var(--danger-soft); }
.quiz-key { width: 22px; height: 22px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 6px; color: var(--muted); font: 10px/1 var(--mono); }
.quiz-feedback { display: none; margin-top: 13px; border-top: 1px solid var(--line); padding-top: 12px; color: var(--muted); font-size: 12.5px; }
.quiz-feedback.visible { display: block; }

.notes-box { border: 1px solid var(--line); border-radius: var(--radius); background: var(--bg-elevated); overflow: hidden; }
.notes-head { display: flex; justify-content: space-between; align-items: center; padding: 10px 13px; border-bottom: 1px solid var(--line); color: var(--muted); font: 10px/1 var(--mono); text-transform: uppercase; letter-spacing: 0; }
.notes-status { text-transform: none; letter-spacing: 0; }
.notes-box textarea { width: 100%; min-height: 180px; resize: vertical; border: 0; outline: 0; background: transparent; color: var(--text); padding: 14px; font: 12.5px/1.65 var(--mono); }
.notes-box textarea::placeholder { color: var(--muted-2); }

.lesson-footer { display: flex; justify-content: space-between; align-items: center; gap: 14px; margin-top: 65px; padding-top: 24px; border-top: 1px solid var(--line); }
.lesson-nav-link { display: grid; max-width: 46%; color: var(--muted); }
.lesson-nav-link:hover { color: var(--text-strong); }
.lesson-nav-link.next { text-align: right; margin-left: auto; }
.lesson-nav-link small { text-transform: uppercase; letter-spacing: 0; font: 9.5px/1 var(--mono); color: var(--muted-2); margin-bottom: 6px; }
.lesson-nav-link strong { font-size: 13px; line-height: 1.35; }

.planner-shell { display: grid; grid-template-columns: minmax(265px, 330px) minmax(0, 1fr); gap: 18px; margin-top: 33px; align-items: start; }
.planner-controls { position: sticky; top: calc(var(--topbar-h) + 20px); border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius-lg); padding: 18px; }
.control-group { padding: 16px 0; border-bottom: 1px solid var(--line); }
.control-group:first-child { padding-top: 0; }
.control-group:last-of-type { border-bottom: 0; }
.control-label { display: flex; justify-content: space-between; align-items: center; gap: 10px; color: var(--text-strong); font-size: 12.5px; font-weight: 700; margin-bottom: 10px; }
.control-label output { color: var(--accent); font: 700 11px/1 var(--mono); }
input[type="range"] { width: 100%; accent-color: var(--accent); }
.input, .select { width: 100%; min-height: 40px; border: 1px solid var(--line); border-radius: 8px; background: var(--bg-soft); color: var(--text); padding: 0 10px; outline: none; }
.input:focus, .select:focus { border-color: var(--accent); box-shadow: 0 0 0 3px var(--accent-soft); }
.day-picker { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; }
.day-toggle { position: relative; }
.day-toggle input { position: absolute; opacity: 0; }
.day-toggle span { display: grid; place-items: center; height: 33px; border: 1px solid var(--line); border-radius: 7px; color: var(--muted); font: 10px/1 var(--mono); cursor: pointer; }
.day-toggle input:checked + span { color: #05241b; background: var(--accent); border-color: var(--accent); font-weight: 800; }
.track-toggle-list { display: grid; gap: 7px; }
.track-toggle { display: flex; justify-content: space-between; align-items: center; gap: 12px; color: var(--text); font-size: 12px; }
.switch { width: 34px; height: 19px; position: relative; flex: 0 0 auto; }
.switch input { position: absolute; opacity: 0; }
.switch span { position: absolute; inset: 0; background: var(--line-strong); border-radius: 99px; cursor: pointer; transition: .18s ease; }
.switch span::after { content: ""; position: absolute; width: 13px; height: 13px; left: 3px; top: 3px; border-radius: 50%; background: #fff; transition: .18s ease; }
.switch input:checked + span { background: var(--accent); }
.switch input:checked + span::after { transform: translateX(15px); }
.planner-buttons { display: flex; gap: 7px; flex-wrap: wrap; margin-top: 16px; }
.plan-summary { display: grid; grid-template-columns: repeat(3, 1fr); gap: 8px; margin-bottom: 12px; }
.plan-summary .stat-card { padding: 11px 12px; }
.plan-summary .stat-card strong { font-size: 17px; }
.plan-week { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: var(--radius); overflow: hidden; margin-bottom: 12px; }
.plan-week-head { display: flex; justify-content: space-between; align-items: center; padding: 12px 14px; background: var(--bg-soft); border-bottom: 1px solid var(--line); }
.plan-week-head strong { color: var(--text-strong); font-size: 12px; }
.plan-week-head span { color: var(--muted); font: 10px/1 var(--mono); }
.plan-session { display: grid; grid-template-columns: 84px minmax(0, 1fr) auto; gap: 12px; align-items: start; padding: 12px 14px; border-bottom: 1px solid var(--line); }
.plan-session:last-child { border-bottom: 0; }
.plan-date { color: var(--muted); font: 10.5px/1.45 var(--mono); }
.plan-task strong { display: block; color: var(--text-strong); font-size: 12.5px; line-height: 1.35; }
.plan-task small { display: block; color: var(--muted); margin-top: 3px; line-height: 1.4; }
.plan-hours { color: var(--accent); font: 700 10.5px/1 var(--mono); padding-top: 3px; }
.empty-state { border: 1px dashed var(--line-strong); border-radius: var(--radius); padding: 40px 24px; text-align: center; color: var(--muted); }
.empty-state strong { display: block; color: var(--text-strong); margin-bottom: 6px; }

.setup-diagram { display: grid; grid-template-columns: 1fr 50px 1fr; gap: 10px; align-items: stretch; margin: 24px 0; }
.stack-box { border: 1px solid var(--line); border-radius: var(--radius); background: var(--bg-elevated); padding: 17px; }
.stack-box h3 { color: var(--text-strong); margin: 0 0 12px; font-size: 15px; }
.stack-layer { border: 1px solid var(--line); border-radius: 8px; background: var(--bg-soft); padding: 9px 11px; color: var(--text); font-size: 11.5px; margin-top: 6px; }
.stack-layer strong { color: var(--accent); font-family: var(--mono); font-size: 10.5px; }
.stack-link { display: grid; place-items: center; color: var(--muted); font: 10px/1.3 var(--mono); text-align: center; }
.stack-link::before, .stack-link::after { content: ""; width: 1px; height: 44px; background: var(--line-strong); }
.checklist { display: grid; gap: 7px; }
.check-item { display: grid; grid-template-columns: 21px minmax(0,1fr); gap: 9px; border: 1px solid var(--line); border-radius: 9px; background: var(--bg-elevated); padding: 10px 11px; cursor: pointer; }
.check-item:hover { border-color: var(--line-strong); }
.check-item input { position: absolute; opacity: 0; }
.check-item .task-box { margin-top: 2px; }
.check-item input:checked + .task-box { background: var(--accent); border-color: var(--accent); }
.check-item input:checked + .task-box::after { content: "✓"; color: #05241b; font-size: 10px; font-weight: 900; }
.check-item strong { display: block; color: var(--text-strong); font-size: 12px; }
.check-item small { display: block; color: var(--muted); margin-top: 3px; line-height: 1.4; }

.resource-group { margin-top: 32px; }
.resource-group h2 { color: var(--text-strong); font-size: 21px; margin-bottom: 13px; }
.resource-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 9px; }
.resource-card { border: 1px solid var(--line); background: var(--bg-elevated); border-radius: 10px; padding: 14px; color: var(--text); }
.resource-card:hover { color: var(--text); border-color: var(--line-strong); background: var(--bg-hover); }
.resource-card .resource-type { color: var(--accent); font: 9.5px/1 var(--mono); text-transform: uppercase; letter-spacing: 0; }
.resource-card strong { display: block; color: var(--text-strong); font-size: 13px; margin: 8px 0 5px; }
.resource-card p { color: var(--muted); font-size: 11.5px; margin: 0; line-height: 1.45; }

.search-dialog { border: 0; padding: 0; background: transparent; width: min(690px, calc(100vw - 28px)); color: var(--text); }
.search-dialog::backdrop { background: rgba(2, 8, 11, .72); backdrop-filter: blur(6px); }
.search-dialog-shell { border: 1px solid var(--line-strong); background: var(--panel-solid); border-radius: 15px; overflow: hidden; box-shadow: var(--shadow); }
.search-input-wrap { display: flex; align-items: center; gap: 10px; padding: 10px 12px; border-bottom: 1px solid var(--line); }
.search-input-wrap svg { width: 19px; height: 19px; fill: none; stroke: var(--muted); stroke-width: 1.8; stroke-linecap: round; }
.search-input-wrap input { flex: 1; min-width: 0; border: 0; outline: 0; background: transparent; color: var(--text-strong); font-size: 16px; }
.search-input-wrap input::placeholder { color: var(--muted-2); }
.search-close { border: 1px solid var(--line); border-radius: 6px; background: var(--bg-soft); color: var(--muted); font: 10px/1 var(--mono); padding: 5px 7px; cursor: pointer; }
.search-results { max-height: min(60vh, 510px); overflow-y: auto; padding: 7px; }
.search-result { display: grid; grid-template-columns: 37px minmax(0, 1fr) auto; align-items: center; gap: 10px; width: 100%; border: 0; border-radius: 9px; background: transparent; color: var(--text); text-align: left; padding: 10px; cursor: pointer; }
.search-result:hover, .search-result.selected { background: var(--bg-hover); }
.search-result-id { width: 37px; height: 34px; display: grid; place-items: center; border-radius: 7px; background: var(--accent-soft); color: var(--accent); font: 700 10px/1 var(--mono); }
.search-result strong { display: block; color: var(--text-strong); font-size: 12.5px; }
.search-result small { display: block; color: var(--muted); line-height: 1.35; margin-top: 3px; }
.search-result-track { color: var(--muted-2); font: 9.5px/1 var(--mono); text-transform: uppercase; }
.search-hint { display: flex; gap: 16px; justify-content: flex-end; padding: 9px 12px; border-top: 1px solid var(--line); color: var(--muted-2); font-size: 10px; }
.search-hint span { display: flex; align-items: center; gap: 4px; }

.toast-region { position: fixed; z-index: 300; right: 18px; bottom: 18px; display: grid; gap: 7px; pointer-events: none; }
.toast { min-width: 230px; max-width: 360px; border: 1px solid var(--line-strong); border-left: 3px solid var(--accent); border-radius: 9px; background: var(--panel-solid); color: var(--text); box-shadow: var(--shadow); padding: 10px 12px; font-size: 12px; animation: toast-in .22s ease both; }
.toast.error { border-left-color: var(--danger); }
@keyframes toast-in { from { opacity: 0; transform: translateY(8px); } }

.mobile-only { display: none; }
.mobile-overlay { position: fixed; inset: var(--topbar-h) 0 0 0; z-index: 80; background: rgba(2, 8, 11, .68); backdrop-filter: blur(4px); }

body.focus-mode #app-shell { grid-template-columns: minmax(0, 1fr); grid-template-areas: "topbar" "main"; }
body.focus-mode .topbar { grid-template-columns: auto minmax(0, 1fr) auto; }
body.focus-mode .sidebar, body.focus-mode .page-toc { display: none; }
body.focus-mode .main-content { padding-left: clamp(28px, 10vw, 140px); padding-right: clamp(28px, 10vw, 140px); }

@media (max-width: 1180px) {
  :root { --toc-w: 0px; }
  #app-shell { grid-template-columns: var(--sidebar-w) minmax(0, 1fr); grid-template-areas: "topbar topbar" "sidebar main"; }
  .topbar { grid-template-columns: var(--sidebar-w) minmax(0, 1fr) auto; }
  .page-toc { display: none; }
  .main-content { padding-left: clamp(28px, 5vw, 70px); padding-right: clamp(28px, 5vw, 70px); }
}

@media (max-width: 840px) {
  :root { --sidebar-w: 272px; }
  #app-shell { display: block; }
  .topbar { display: grid; grid-template-columns: minmax(0, 1fr) auto; height: var(--topbar-h); }
  .topbar-left { padding: 0 12px; gap: 8px; }
  .top-nav { display: none; }
  .topbar-actions { padding: 0 10px; }
  .search-trigger { width: 36px; min-width: 36px; padding: 0; display: grid; place-items: center; }
  .search-trigger span, .search-trigger kbd { display: none; }
  .mobile-only { display: grid; }
  .desktop-only { display: none; }
  .sidebar { position: fixed; z-index: 90; top: var(--topbar-h); left: 0; transform: translateX(-102%); transition: transform .22s ease; box-shadow: var(--shadow); }
  .sidebar.open { transform: translateX(0); }
  .main-content { min-height: calc(100vh - var(--topbar-h)); padding: 36px 22px 80px; }
  .module-grid, .resource-grid { grid-template-columns: 1fr; }
  .path-panel { grid-template-columns: 1fr; }
  .orientation-grid { grid-template-columns: 1fr; }
  .orientation-block, .orientation-block:nth-child(even) { padding: 19px 0; border-left: 0; }
  .background-grid { grid-template-columns: 1fr; }
  .background-grid > div { padding: 18px 0; }
  .background-grid > div + div { padding-left: 0; border-left: 0; border-top: 1px solid var(--line); }
  .principles-grid { grid-template-columns: 1fr; }
  .planner-shell { grid-template-columns: 1fr; }
  .planner-controls { position: static; }
  .setup-diagram { grid-template-columns: 1fr; }
  .stack-link { grid-template-columns: 1fr auto 1fr; }
  .stack-link::before, .stack-link::after { width: 100%; height: 1px; }
}

@media (max-width: 600px) {
  body { font-size: 15px; }
  .brand-copy small { display: none; }
  .brand-copy strong { font-size: 12px; }
  .page-title, .lesson-title { font-size: 39px; }
  .page-lede, .lesson-lede { font-size: 17px; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .course-facts { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .course-facts div { padding: 12px 10px; border-bottom: 1px solid var(--line); }
  .course-facts div:nth-child(2) { border-right: 0; }
  .course-facts div:nth-last-child(-n + 2) { border-bottom: 0; }
  .course-facts div:nth-child(odd) { padding-left: 0; }
  .continue-strip { align-items: flex-start; flex-direction: column; }
  .module-row { grid-template-columns: 34px minmax(0, 1fr) 26px; gap: 10px; }
  .module-details { display: none; }
  .objectives { grid-template-columns: 1fr; }
  .path-flow { grid-template-columns: 1fr; }
  .path-node:not(:last-child)::after { content: "↓"; right: 50%; bottom: -14px; top: auto; }
  .plan-summary { grid-template-columns: 1fr 1fr; }
  .plan-session { grid-template-columns: 68px minmax(0, 1fr); }
  .plan-hours { grid-column: 2; }
  .lesson-footer { align-items: flex-start; }
  .lesson-nav-link { max-width: 48%; }
  .search-hint { display: none; }
}

@media (max-width: 350px) {
  .brand-copy { display: none; }
}

@media print {
  .topbar, .sidebar, .page-toc, .lesson-actions, .lesson-footer, .toast-region { display: none !important; }
  #app-shell { display: block; }
  .main-content { padding: 0; }
  body { background: #fff; color: #222; }
  .content-wrap { max-width: none; }
}