/* DREA Learn — brand tokens */
:root {
  --dark: #0A1F1F;
  --accent: #1A7A6D;
  --light: #EFF8F6;
  --brand-light: #2E9E8F;
  --light-border: #D4ECE8;
  --muted-text: #5A7D78;
  --bg: #FAFCFB;
  --ink: #0A1F1F;
  --paper: #FFFFFF;
  --gold: #C9A858;
  --gold-soft: #F5ECD6;
  --danger: #B04848;
  --serif: 'Bricolage Grotesque', 'Georgia', serif;
  --sans: 'Nunito Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --max-prose: 680px;
  --max-wide: 1120px;
  --ease: cubic-bezier(0.2, 0.8, 0.2, 1);
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html, body { background: var(--bg); color: var(--ink); font-family: var(--sans); line-height: 1.6; font-size: 16px; -webkit-font-smoothing: antialiased; }
.serif { font-family: var(--serif); letter-spacing: -0.01em; }
.sans { font-family: var(--sans); }
a { color: var(--accent); text-decoration: none; transition: color 180ms var(--ease); }
a:hover { color: var(--dark); }

/* page fade-in */
@keyframes fadeUp { from { opacity: 0; transform: translateY(8px); } to { opacity: 1; transform: translateY(0); } }
main > * { animation: fadeUp 500ms var(--ease) both; }
main > *:nth-child(2) { animation-delay: 80ms; }
main > *:nth-child(3) { animation-delay: 160ms; }

/* ------- Top nav ------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(250, 252, 251, 0.86);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--light-border);
}
.nav-inner {
  max-width: var(--max-wide);
  margin: 0 auto;
  padding: 14px 28px;
  display: flex; align-items: center; justify-content: space-between;
  gap: 24px;
}
.brand-mark {
  display: flex; align-items: center; gap: 10px;
  font-family: var(--serif); font-weight: 600; font-size: 15px; color: var(--dark);
  letter-spacing: -0.01em;
}
.brand-mark .dot {
  width: 26px; height: 26px; border-radius: 7px;
  background: linear-gradient(165deg, var(--accent) 0%, var(--brand-light) 100%);
  display: inline-flex; align-items: center; justify-content: center;
  color: var(--light); font-weight: 700; font-size: 13px;
  box-shadow: 0 2px 6px -2px rgba(26, 122, 109, 0.4);
}
.nav-right { display: flex; align-items: center; gap: 14px; font-size: 13px; }
.nav-right > a { color: var(--muted-text); font-weight: 500; padding: 6px 0; }
.nav-right > a:hover { color: var(--dark); }

/* gamification pills in nav */
.stat-pill {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 6px 12px; border-radius: 999px;
  font-weight: 700; font-size: 12px;
  transition: transform 200ms var(--ease);
  letter-spacing: 0.02em;
}
.stat-pill:hover { transform: translateY(-1px); }
.stat-pill svg { width: 13px; height: 13px; }
.stat-pill .num { font-variant-numeric: tabular-nums; }
.pill-streak { background: rgba(185, 89, 31, 0.1); color: #B2591F; }
.pill-xp { background: rgba(26, 122, 109, 0.1); color: var(--accent); }
.pill-level { background: var(--dark); color: var(--light); }
.pill-level .num { font-family: var(--serif); }

.cta-sm {
  padding: 7px 14px; border-radius: 999px;
  background: var(--dark); color: var(--light) !important;
  font-weight: 600; font-size: 12px;
  transition: transform 180ms var(--ease), background 180ms var(--ease);
}
.cta-sm:hover { background: var(--accent); transform: translateY(-1px); color: var(--light) !important; }

/* ------- Lesson page ------- */
.lesson-wrap { max-width: var(--max-prose); margin: 0 auto; padding: 40px 28px 120px; }
.lesson-meta {
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  font-size: 11px; font-weight: 600; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--muted-text);
  margin-bottom: 24px;
}
.lesson-meta .dot-sep { width: 3px; height: 3px; border-radius: 50%; background: var(--muted-text); opacity: 0.6; }
.lesson-meta a { color: var(--accent); letter-spacing: 0.14em; }

.lesson h1 {
  font-family: var(--serif); font-weight: 600;
  font-size: clamp(32px, 4.5vw, 46px);
  line-height: 1.08; letter-spacing: -0.025em;
  color: var(--dark);
  margin-bottom: 32px;
}
.lesson h2 {
  font-family: var(--serif); font-weight: 600;
  font-size: 24px; line-height: 1.22; letter-spacing: -0.01em;
  color: var(--dark);
  margin: 48px 0 14px;
}
.lesson h3 {
  font-family: var(--serif); font-weight: 600;
  font-size: 18px; color: var(--dark);
  margin: 32px 0 8px;
}
.lesson p { margin-bottom: 20px; font-size: 17px; line-height: 1.72; color: #15302E; }
.lesson strong { color: var(--dark); font-weight: 700; }
.lesson em { color: var(--dark); font-style: italic; }
.lesson ul, .lesson ol { margin: 0 0 22px 24px; }
.lesson li { margin-bottom: 8px; font-size: 17px; line-height: 1.65; }
.lesson blockquote {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 18px;
  margin: 24px 0;
  color: var(--muted-text);
  font-style: italic;
}
.lesson hr { border: none; border-top: 1px solid var(--light-border); margin: 48px 0; }

/* reading progress */
.read-progress { position: fixed; top: 0; left: 0; right: 0; height: 3px; background: transparent; z-index: 60; }
.read-progress-fill { height: 100%; width: 0%; background: var(--accent); transition: width 100ms linear; }

/* ------- Lesson hero visual ------- */
.lesson-hero {
  position: relative;
  margin: 0 -28px 36px;
  padding: 56px 36px 52px;
  border-radius: 0;
  background: linear-gradient(165deg, var(--dark) 0%, #11423C 50%, var(--accent) 100%);
  color: var(--light);
  overflow: hidden;
}
@media (min-width: 720px) {
  .lesson-hero { margin: 0 0 40px; padding: 72px 56px; border-radius: 24px; }
}
.lesson-hero::before {
  content: ''; position: absolute; inset: 0;
  background-image:
    radial-gradient(circle at 90% 10%, rgba(46, 158, 143, 0.4), transparent 40%),
    radial-gradient(circle at 10% 90%, rgba(201, 168, 88, 0.15), transparent 30%);
  pointer-events: none;
}
.lesson-hero > * { position: relative; z-index: 1; }
.lesson-hero .eyebrow {
  font-size: 11px; font-weight: 700; letter-spacing: 0.2em; text-transform: uppercase;
  color: var(--brand-light); margin-bottom: 18px;
}
.lesson-hero h1 {
  font-family: var(--serif); font-weight: 600;
  font-size: clamp(32px, 5vw, 48px);
  line-height: 1.05; letter-spacing: -0.025em;
  color: var(--light);
  margin-bottom: 18px;
  max-width: 680px;
}
.lesson-hero .lede {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(17px, 2vw, 20px);
  line-height: 1.5; color: rgba(239, 248, 246, 0.8);
  max-width: 580px; letter-spacing: -0.005em;
}
.lesson-hero .meta-inline {
  display: flex; gap: 18px; flex-wrap: wrap; margin-top: 32px;
  font-size: 11px; font-weight: 600; letter-spacing: 0.14em; text-transform: uppercase;
  color: rgba(239, 248, 246, 0.55);
}
.lesson-hero .meta-inline .bright { color: var(--brand-light); }

/* ------- Visual blocks inside lessons ------- */

/* big stat card */
.stat-card {
  margin: 32px 0;
  padding: 36px 32px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  box-shadow: 0 8px 28px -14px rgba(10, 31, 31, 0.1);
  text-align: center;
}
.stat-card .big {
  font-family: var(--serif); font-weight: 600;
  font-size: clamp(48px, 8vw, 80px);
  line-height: 0.95; letter-spacing: -0.04em;
  color: var(--dark);
  margin-bottom: 10px;
  background: linear-gradient(165deg, var(--dark) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.stat-card .lbl {
  font-family: var(--sans); font-weight: 600; font-size: 13px;
  letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 14px;
}
.stat-card .ctx { font-size: 14px; color: var(--muted-text); line-height: 1.55; max-width: 420px; margin: 0 auto; }

/* key facts grid */
.facts-grid {
  margin: 32px 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 14px;
}
.fact-card {
  padding: 22px 20px;
  border-radius: 14px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  transition: transform 220ms var(--ease), border-color 220ms var(--ease);
}
.fact-card:hover { transform: translateY(-3px); border-color: var(--accent); }
.fact-card .icon {
  width: 36px; height: 36px; border-radius: 10px;
  background: rgba(26, 122, 109, 0.1);
  display: flex; align-items: center; justify-content: center;
  color: var(--accent); margin-bottom: 14px;
}
.fact-card .icon svg { width: 18px; height: 18px; }
.fact-card .title { font-family: var(--serif); font-size: 15px; font-weight: 600; color: var(--dark); margin-bottom: 6px; letter-spacing: -0.005em; }
.fact-card .desc { font-size: 13px; color: var(--muted-text); line-height: 1.5; }

/* comparison side-by-side */
.compare {
  margin: 36px 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}
@media (max-width: 640px) { .compare { grid-template-columns: 1fr; } }
.compare .col {
  padding: 28px 24px;
  border-radius: 18px;
}
.compare .col-good { background: rgba(26, 122, 109, 0.06); border: 1px solid rgba(26, 122, 109, 0.2); }
.compare .col-bad { background: rgba(176, 72, 72, 0.05); border: 1px solid rgba(176, 72, 72, 0.18); }
.compare .lbl {
  font-size: 10px; font-weight: 700; letter-spacing: 0.18em; text-transform: uppercase;
  margin-bottom: 14px;
}
.compare .col-good .lbl { color: var(--accent); }
.compare .col-bad .lbl { color: #8a2e2e; }
.compare h4 { font-family: var(--serif); font-size: 17px; font-weight: 600; color: var(--dark); margin-bottom: 8px; letter-spacing: -0.005em; }
.compare p { font-size: 14px; color: var(--muted-text); line-height: 1.55; margin: 0 0 8px; }
.compare ul { margin: 0 0 0 18px; padding: 0; }
.compare li { font-size: 13.5px; color: var(--dark); margin-bottom: 6px; line-height: 1.5; }

/* timeline / cycle chart */
.cycle-chart {
  margin: 36px 0;
  padding: 32px 28px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  box-shadow: 0 8px 28px -14px rgba(10, 31, 31, 0.1);
}
.cycle-chart .ttl {
  font-family: var(--serif); font-weight: 600; font-size: 18px;
  color: var(--dark); margin-bottom: 4px; letter-spacing: -0.01em;
}
.cycle-chart .sub { font-size: 13px; color: var(--muted-text); margin-bottom: 24px; }
.cycle-chart svg { width: 100%; height: auto; }
.cycle-chart .legend {
  display: flex; gap: 18px; flex-wrap: wrap; margin-top: 18px;
  font-size: 12px; color: var(--muted-text);
}
.cycle-chart .legend span { display: inline-flex; align-items: center; gap: 6px; }
.cycle-chart .legend i { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }

/* numbered list blocks */
.numbered {
  margin: 32px 0;
  counter-reset: step;
}
.numbered-item {
  display: flex; align-items: flex-start; gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--light-border);
  counter-increment: step;
}
.numbered-item:last-child { border-bottom: none; }
.numbered-item::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--serif); font-size: 30px; font-weight: 300;
  color: var(--accent);
  min-width: 44px;
  line-height: 1;
}
.numbered-item h4 { font-family: var(--serif); font-size: 16px; font-weight: 600; color: var(--dark); margin-bottom: 4px; letter-spacing: -0.005em; }
.numbered-item p { font-size: 14px; color: var(--muted-text); margin: 0; line-height: 1.55; }

/* pull-quote */
.pull-quote {
  margin: 40px 0;
  padding: 36px 32px;
  border-radius: 20px;
  background: linear-gradient(165deg, var(--light) 0%, #E4F1ED 100%);
  border: 1px solid var(--light-border);
  position: relative;
}
.pull-quote::before {
  content: '"'; position: absolute; top: -12px; left: 24px;
  font-family: var(--serif); font-size: 96px; line-height: 1;
  color: var(--accent); opacity: 0.2;
}
.pull-quote .q {
  font-family: var(--serif); font-weight: 500; font-size: 22px;
  line-height: 1.35; color: var(--dark); letter-spacing: -0.015em;
}

/* caption under visuals */
.caption {
  font-size: 12px; color: var(--muted-text); font-style: italic; text-align: center;
  margin-top: 10px;
}

/* ----- illus figure ----- */
.illus {
  margin: 36px 0;
  padding: 20px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  box-shadow: 0 8px 28px -14px rgba(10, 31, 31, 0.1);
}
.illus svg { display: block; width: 100%; height: auto; max-height: 340px; }

/* ----- callouts (tip / warning / note) ----- */
.callout {
  margin: 28px 0;
  padding: 22px 24px;
  border-radius: 16px;
  display: flex; gap: 18px; align-items: flex-start;
  border: 1px solid var(--light-border);
  background: var(--paper);
}
.callout-icon {
  flex-shrink: 0;
  width: 40px; height: 40px; border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
}
.callout-icon svg { width: 20px; height: 20px; }
.callout-body { flex: 1; font-size: 15px; line-height: 1.55; color: var(--dark); }
.callout-body p { margin-bottom: 0; font-size: 15px; }
.callout-ttl { font-family: var(--serif); font-size: 14px; font-weight: 700; margin-bottom: 4px; letter-spacing: -0.005em; text-transform: uppercase; letter-spacing: 0.08em; }

.callout-tip { background: rgba(26, 122, 109, 0.05); border-color: rgba(26, 122, 109, 0.25); }
.callout-tip .callout-icon { background: var(--accent); color: var(--light); }
.callout-tip .callout-ttl { color: var(--accent); }

.callout-warning { background: rgba(201, 168, 88, 0.08); border-color: rgba(201, 168, 88, 0.4); }
.callout-warning .callout-icon { background: var(--gold); color: var(--dark); }
.callout-warning .callout-ttl { color: #8a6f2e; }

.callout-note { background: rgba(46, 158, 143, 0.06); border-color: rgba(46, 158, 143, 0.25); }
.callout-note .callout-icon { background: var(--brand-light); color: var(--light); }
.callout-note .callout-ttl { color: var(--accent); }

/* ----- stat row (3 columns) ----- */
.stat-row {
  margin: 32px 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
  padding: 28px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
}
.stat-row-item { text-align: left; padding: 0 12px; border-left: 2px solid var(--accent); }
.stat-row-item:first-child { border-left: none; padding-left: 0; }
.stat-row-item .lbl { font-size: 10px; font-weight: 700; letter-spacing: 0.16em; text-transform: uppercase; color: var(--accent); margin-bottom: 8px; }
.stat-row-item .big {
  font-family: var(--serif); font-weight: 600;
  font-size: clamp(28px, 4vw, 38px); line-height: 1; letter-spacing: -0.025em;
  color: var(--dark); margin-bottom: 8px;
}
.stat-row-item .ctx { font-size: 13px; color: var(--muted-text); line-height: 1.5; }

/* ----- data table ----- */
.data-table-wrap {
  margin: 32px 0;
  overflow-x: auto;
  border-radius: 14px;
  border: 1px solid var(--light-border);
  background: var(--paper);
}
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}
.data-table th {
  text-align: left;
  padding: 14px 18px;
  font-size: 11px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase;
  color: var(--muted-text);
  border-bottom: 1px solid var(--light-border);
  background: rgba(26, 122, 109, 0.03);
}
.data-table td {
  padding: 14px 18px;
  color: var(--dark);
  border-bottom: 1px solid var(--light-border);
  font-weight: 500;
}
.data-table tr:last-child td { border-bottom: none; }
.data-table tr:hover td { background: rgba(26, 122, 109, 0.02); }

/* lesson foot + completion */
.complete-zone {
  margin: 48px 0 0;
  padding: 40px 32px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  text-align: center;
}
.complete-zone h4 { font-family: var(--serif); font-size: 20px; font-weight: 600; color: var(--dark); margin-bottom: 6px; }
.complete-zone p { font-size: 14px; color: var(--muted-text); margin-bottom: 22px; }

.mark-complete {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 14px 26px; border-radius: 999px;
  background: var(--dark); color: var(--light);
  font-family: var(--sans); font-weight: 700; font-size: 13px;
  border: none; cursor: pointer;
  letter-spacing: 0.04em; text-transform: uppercase;
  transition: transform 180ms var(--ease), background 180ms var(--ease), box-shadow 180ms var(--ease);
  box-shadow: 0 8px 22px -10px rgba(10, 31, 31, 0.4);
}
.mark-complete:hover { transform: translateY(-2px); background: var(--accent); box-shadow: 0 12px 26px -10px rgba(26, 122, 109, 0.5); }
.mark-complete.done { background: var(--accent); pointer-events: none; }
.mark-complete svg { width: 14px; height: 14px; }
.xp-bump {
  position: absolute; font-family: var(--serif); font-weight: 700; font-size: 14px;
  color: var(--accent); pointer-events: none; opacity: 0;
}
.xp-bump.go { animation: xpBump 1200ms var(--ease) forwards; }
@keyframes xpBump {
  0% { opacity: 0; transform: translateY(0); }
  20% { opacity: 1; }
  100% { opacity: 0; transform: translateY(-48px); }
}

.lesson-foot {
  display: flex; justify-content: space-between; gap: 18px;
  margin-top: 32px; padding-top: 32px;
  border-top: 1px solid var(--light-border);
}
.lesson-foot a {
  display: flex; flex-direction: column; gap: 4px;
  padding: 16px 20px; border-radius: 14px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  flex: 1;
  transition: transform 180ms var(--ease), border-color 180ms var(--ease), box-shadow 180ms var(--ease);
}
.lesson-foot a:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 10px 24px -12px rgba(26, 122, 109, 0.28);
}
.lesson-foot .label { font-size: 11px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted-text); }
.lesson-foot .title { font-family: var(--serif); font-size: 15px; color: var(--dark); font-weight: 600; letter-spacing: -0.005em; }
.lesson-foot .prev { text-align: left; }
.lesson-foot .next { text-align: right; }
.lesson-foot .next.primary { background: var(--dark); border-color: var(--dark); }
.lesson-foot .next.primary .label { color: rgba(239, 248, 246, 0.65); }
.lesson-foot .next.primary .title { color: var(--light); }
.lesson-foot .next.primary:hover { background: var(--accent); border-color: var(--accent); }

/* ------- Landing page ------- */
.hero {
  max-width: var(--max-wide); margin: 0 auto;
  padding: 96px 28px 72px;
  text-align: center;
  position: relative;
}
.hero::before {
  content: ''; position: absolute; inset: 0; pointer-events: none;
  background-image: radial-gradient(circle at 50% 0%, rgba(26, 122, 109, 0.08), transparent 50%);
}
.hero > * { position: relative; }
.hero .eyebrow {
  display: inline-block;
  font-size: 11px; font-weight: 700; letter-spacing: 0.18em;
  color: var(--accent); text-transform: uppercase;
  margin-bottom: 24px;
  padding: 6px 14px; border-radius: 999px;
  background: rgba(26, 122, 109, 0.1);
}
.hero h1 {
  font-family: var(--serif); font-weight: 600;
  font-size: clamp(44px, 6.5vw, 80px);
  line-height: 1.02; letter-spacing: -0.035em;
  color: var(--dark);
  margin-bottom: 24px;
  max-width: 920px; margin-left: auto; margin-right: auto;
}
.hero p.lead {
  font-family: var(--serif); font-weight: 400;
  font-size: clamp(18px, 2vw, 22px); line-height: 1.45;
  color: var(--muted-text); letter-spacing: -0.005em;
  max-width: 640px; margin: 0 auto 40px;
}
.hero-cta { display: inline-flex; gap: 12px; align-items: center; flex-wrap: wrap; justify-content: center; }
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 28px; border-radius: 999px;
  background: var(--dark); color: var(--light) !important;
  font-weight: 700; font-size: 14px;
  transition: transform 200ms var(--ease), background 200ms var(--ease), box-shadow 200ms var(--ease);
  box-shadow: 0 12px 28px -12px rgba(10, 31, 31, 0.4);
}
.btn-primary:hover { background: var(--accent); transform: translateY(-2px); box-shadow: 0 16px 32px -10px rgba(26, 122, 109, 0.5); }
.btn-ghost {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 22px; border-radius: 999px;
  color: var(--muted-text) !important;
  font-weight: 600; font-size: 14px;
  border: 1px solid var(--light-border);
  transition: border-color 180ms var(--ease), color 180ms var(--ease), background 180ms var(--ease);
}
.btn-ghost:hover { color: var(--dark) !important; border-color: var(--accent); background: rgba(26, 122, 109, 0.04); }

.stats {
  display: flex; gap: 48px; justify-content: center;
  margin-top: 56px;
  flex-wrap: wrap;
}
.stat .num { font-family: var(--serif); font-size: 36px; font-weight: 600; color: var(--dark); letter-spacing: -0.02em; }
.stat .lbl { font-size: 12px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted-text); font-weight: 700; margin-top: 4px; }

/* curriculum grid */
.curriculum {
  max-width: var(--max-wide); margin: 72px auto 120px;
  padding: 0 28px;
}
.curriculum h2 {
  font-family: var(--serif); font-size: clamp(32px, 4vw, 44px); font-weight: 600;
  color: var(--dark); letter-spacing: -0.025em;
  margin-bottom: 10px;
}
.curriculum .sub { color: var(--muted-text); margin-bottom: 48px; font-size: 17px; max-width: 560px; }
.chapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 18px;
}
.chapter-card {
  padding: 28px 26px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--light-border);
  transition: transform 260ms var(--ease), border-color 260ms var(--ease), box-shadow 260ms var(--ease);
  position: relative; overflow: hidden;
  color: var(--dark) !important;
}
.chapter-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  box-shadow: 0 20px 40px -20px rgba(26, 122, 109, 0.3);
}
.chapter-card.locked { opacity: 0.55; pointer-events: none; }
.chapter-card .num {
  font-family: var(--serif); font-size: 13px; font-weight: 500;
  color: var(--accent); letter-spacing: 0.1em;
  margin-bottom: 14px; text-transform: uppercase;
}
.chapter-card h3 {
  font-family: var(--serif); font-size: 24px; font-weight: 600;
  color: var(--dark); letter-spacing: -0.02em;
  margin-bottom: 8px; line-height: 1.12;
}
.chapter-card p {
  font-size: 14px; color: var(--muted-text);
  line-height: 1.55; margin-bottom: 22px;
}
.chapter-card .foot {
  display: flex; align-items: center; justify-content: space-between;
  font-size: 12px; color: var(--muted-text); font-weight: 600; letter-spacing: 0.04em;
}
.chapter-card .premium-badge {
  position: absolute; top: 18px; right: 18px;
  font-size: 10px; font-weight: 700; letter-spacing: 0.14em;
  padding: 4px 10px; border-radius: 999px;
  background: var(--gold); color: var(--dark);
  text-transform: uppercase;
}
.chapter-card .progress-mini {
  height: 3px; background: var(--light-border); border-radius: 999px;
  margin-top: 16px; overflow: hidden;
}
.chapter-card .progress-mini-fill { height: 100%; background: var(--accent); border-radius: 999px; transition: width 500ms var(--ease); }

/* user dashboard on landing (when signed in) */
.dashboard {
  max-width: var(--max-wide); margin: 0 auto; padding: 40px 28px 0;
}
.dash-card {
  padding: 32px 30px;
  border-radius: 20px;
  background: linear-gradient(165deg, var(--dark) 0%, #0F3631 70%, var(--accent) 100%);
  color: var(--light);
  display: grid; grid-template-columns: 1fr auto; gap: 24px; align-items: center;
}
@media (max-width: 640px) { .dash-card { grid-template-columns: 1fr; } }
.dash-card h3 { font-family: var(--serif); font-size: 22px; font-weight: 600; margin-bottom: 4px; letter-spacing: -0.01em; }
.dash-card .sub { font-size: 14px; opacity: 0.7; margin-bottom: 20px; }
.dash-stats { display: flex; gap: 28px; flex-wrap: wrap; }
.dash-stat .n { font-family: var(--serif); font-size: 32px; font-weight: 600; letter-spacing: -0.02em; line-height: 1; }
.dash-stat .l { font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase; opacity: 0.6; font-weight: 700; margin-top: 4px; }
.dash-ring {
  width: 120px; height: 120px; position: relative;
}
.dash-ring svg { transform: rotate(-90deg); }
.dash-ring .label { position: absolute; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; }
.dash-ring .label .p { font-family: var(--serif); font-size: 26px; font-weight: 600; letter-spacing: -0.02em; }
.dash-ring .label .l { font-size: 10px; letter-spacing: 0.12em; text-transform: uppercase; opacity: 0.7; font-weight: 700; }

/* achievements strip */
.achievements {
  max-width: var(--max-wide); margin: 32px auto 0;
  padding: 0 28px;
  display: flex; gap: 12px; flex-wrap: wrap;
}
.badge {
  padding: 8px 14px; border-radius: 999px;
  font-size: 12px; font-weight: 700; letter-spacing: 0.04em;
  display: inline-flex; align-items: center; gap: 6px;
  background: var(--paper); border: 1px solid var(--light-border); color: var(--muted-text);
}
.badge.earned { color: var(--accent); border-color: var(--accent); background: rgba(26, 122, 109, 0.05); }
.badge svg { width: 12px; height: 12px; }

/* ------- Chapter page ------- */
.chapter-hero {
  max-width: var(--max-prose); margin: 0 auto;
  padding: 64px 28px 24px;
}
.chapter-hero .num {
  font-size: 12px; letter-spacing: 0.18em; text-transform: uppercase;
  color: var(--accent); font-weight: 700;
  margin-bottom: 14px;
}
.chapter-hero h1 {
  font-family: var(--serif); font-size: clamp(36px, 5.5vw, 60px);
  font-weight: 600; letter-spacing: -0.03em; color: var(--dark);
  line-height: 1.04; margin-bottom: 16px;
}
.chapter-hero .sub { font-family: var(--serif); font-size: clamp(17px, 2vw, 21px); color: var(--muted-text); line-height: 1.42; letter-spacing: -0.005em; max-width: 580px; }

.chapter-progress-box {
  max-width: var(--max-prose); margin: 16px auto 32px; padding: 0 28px;
  display: flex; gap: 20px; align-items: center;
}
.chapter-progress-box .ring { flex-shrink: 0; }
.chapter-progress-box .ring-wrap {
  position: relative; width: 72px; height: 72px;
}
.chapter-progress-box .ring-wrap svg { transform: rotate(-90deg); }
.chapter-progress-box .ring-wrap .label { position: absolute; inset: 0; display: flex; flex-direction: column; align-items: center; justify-content: center; }
.chapter-progress-box .ring-wrap .label .p { font-family: var(--serif); font-size: 16px; font-weight: 600; color: var(--dark); letter-spacing: -0.01em; line-height: 1; }
.chapter-progress-box .ring-wrap .label .l { font-size: 8px; letter-spacing: 0.1em; text-transform: uppercase; color: var(--muted-text); font-weight: 700; margin-top: 2px; }
.chapter-progress-box .meta { flex: 1; }
.chapter-progress-box .meta .ttl { font-family: var(--serif); font-size: 15px; color: var(--dark); font-weight: 600; margin-bottom: 2px; letter-spacing: -0.005em; }
.chapter-progress-box .meta .desc { font-size: 12.5px; color: var(--muted-text); line-height: 1.5; }

.lesson-list { max-width: var(--max-prose); margin: 0 auto 40px; padding: 0 28px; }
.lesson-list a {
  display: flex; align-items: center; gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--light-border);
  transition: padding-left 220ms var(--ease);
}
.lesson-list a:hover { padding-left: 10px; }
.lesson-list .idx {
  font-family: var(--serif); font-size: 14px; color: var(--muted-text);
  font-weight: 500; min-width: 34px;
}
.lesson-list .ttl {
  font-family: var(--serif); font-size: 17px; color: var(--dark);
  font-weight: 500; flex: 1; letter-spacing: -0.005em;
}
.lesson-list .mins { font-size: 12px; color: var(--muted-text); font-weight: 600; letter-spacing: 0.04em; }
.lesson-list .check {
  width: 20px; height: 20px; border-radius: 50%;
  border: 1.5px solid var(--light-border);
  display: inline-flex; align-items: center; justify-content: center;
  flex-shrink: 0; transition: all 220ms var(--ease);
}
.lesson-list .check.done {
  background: var(--accent); border-color: var(--accent); color: var(--light);
  box-shadow: 0 0 0 3px rgba(26, 122, 109, 0.12);
}
.lesson-list .check svg { width: 10px; height: 10px; opacity: 0; }
.lesson-list .check.done svg { opacity: 1; }

.chapter-foot { max-width: var(--max-prose); margin: 0 auto 120px; padding: 0 28px; display: flex; gap: 18px; }
.quiz-cta {
  flex: 1; padding: 32px 30px; border-radius: 20px;
  background: linear-gradient(165deg, var(--dark) 0%, var(--accent) 100%);
  color: var(--light) !important; display: block;
  transition: transform 220ms var(--ease), box-shadow 220ms var(--ease);
  position: relative; overflow: hidden;
}
.quiz-cta::after {
  content: '→'; position: absolute; right: 28px; top: 50%;
  transform: translateY(-50%); font-size: 28px; opacity: 0.4;
  transition: transform 220ms var(--ease), opacity 220ms var(--ease);
}
.quiz-cta:hover { transform: translateY(-3px); box-shadow: 0 24px 40px -16px rgba(26, 122, 109, 0.5); }
.quiz-cta:hover::after { transform: translateY(-50%) translateX(6px); opacity: 0.9; }
.quiz-cta .lbl { font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; opacity: 0.7; margin-bottom: 8px; font-weight: 700; }
.quiz-cta h4 { font-family: var(--serif); font-size: 22px; font-weight: 600; margin-bottom: 6px; letter-spacing: -0.01em; color: var(--light); }
.quiz-cta .desc { font-size: 13px; opacity: 0.75; }

/* ------- Quiz page ------- */
.quiz-wrap { max-width: 640px; margin: 0 auto; padding: 56px 28px 120px; }
.quiz-head { text-align: center; margin-bottom: 42px; }
.quiz-head .lbl { font-size: 11px; letter-spacing: 0.18em; text-transform: uppercase; color: var(--accent); font-weight: 700; margin-bottom: 10px; }
.quiz-head h1 { font-family: var(--serif); font-size: clamp(30px, 4vw, 40px); font-weight: 600; color: var(--dark); letter-spacing: -0.025em; }
.quiz-head .sub { font-size: 15px; color: var(--muted-text); margin-top: 10px; }
.question {
  background: var(--paper);
  border: 1px solid var(--light-border);
  border-radius: 18px;
  padding: 30px;
  margin-bottom: 18px;
}
.question .q-num { font-size: 11px; letter-spacing: 0.14em; text-transform: uppercase; color: var(--muted-text); font-weight: 700; margin-bottom: 12px; }
.question .q-text { font-family: var(--serif); font-size: 20px; color: var(--dark); font-weight: 600; line-height: 1.3; margin-bottom: 22px; letter-spacing: -0.015em; }
.choices { display: flex; flex-direction: column; gap: 10px; }
.choice {
  display: flex; align-items: center; gap: 14px;
  padding: 14px 18px;
  border: 1.5px solid var(--light-border);
  border-radius: 12px;
  cursor: pointer;
  transition: border-color 160ms var(--ease), background 160ms var(--ease);
  font-size: 15px; color: var(--dark);
  background: var(--paper); width: 100%; text-align: left;
  font-family: inherit;
}
.choice:hover { border-color: var(--accent); background: rgba(26, 122, 109, 0.03); }
.choice.selected { border-color: var(--accent); background: rgba(26, 122, 109, 0.06); }
.choice.correct { border-color: var(--accent); background: rgba(26, 122, 109, 0.12); }
.choice.incorrect { border-color: var(--danger); background: rgba(176, 72, 72, 0.06); color: #802020; }
.choice .radio {
  width: 20px; height: 20px; border-radius: 50%;
  border: 1.5px solid var(--muted-text);
  flex-shrink: 0; display: inline-flex; align-items: center; justify-content: center;
  transition: all 180ms var(--ease);
}
.choice.selected .radio, .choice.correct .radio { border-color: var(--accent); background: var(--accent); }
.choice.selected .radio::after, .choice.correct .radio::after { content: ''; width: 7px; height: 7px; border-radius: 50%; background: var(--light); }
.choice.incorrect .radio { border-color: var(--danger); background: var(--danger); }
.choice.incorrect .radio::after { content: ''; width: 7px; height: 7px; border-radius: 50%; background: #FFFFFF; }
.q-actions { margin-top: 18px; display: flex; justify-content: flex-end; }
.q-submit {
  padding: 10px 20px; border-radius: 999px;
  background: var(--dark); color: var(--light);
  border: none; cursor: pointer;
  font-family: var(--sans); font-weight: 700; font-size: 12px;
  letter-spacing: 0.06em; text-transform: uppercase;
  transition: transform 180ms var(--ease), background 180ms var(--ease), opacity 180ms var(--ease);
}
.q-submit:not(:disabled):hover { background: var(--accent); transform: translateY(-1px); }
.q-submit:disabled { opacity: 0.35; cursor: not-allowed; }
.q-submit.done { background: var(--accent); opacity: 0.9; cursor: default; }

.explain {
  margin-top: 16px; padding: 16px 18px;
  border-radius: 12px; background: rgba(26, 122, 109, 0.06);
  font-size: 14px; color: var(--dark); line-height: 1.55;
  display: none;
  border-left: 3px solid var(--accent);
}
.explain.shown { display: block; animation: fadeUp 320ms var(--ease) both; }
.explain-verdict {
  font-family: var(--serif); font-size: 13px; font-weight: 700;
  letter-spacing: 0.12em; text-transform: uppercase;
  margin-bottom: 8px;
}
.explain-verdict.v-good { color: var(--accent); }
.explain-verdict.v-bad { color: #B04848; }
.explain-body { font-size: 14px; line-height: 1.55; color: var(--dark); }

.quiz-progress-bar {
  display: inline-flex; align-items: center; gap: 8px;
  margin-top: 18px; padding: 6px 14px;
  border-radius: 999px;
  background: rgba(26, 122, 109, 0.08);
  color: var(--accent); font-size: 12px; font-weight: 700;
  letter-spacing: 0.04em;
}
.quiz-progress-count { font-variant-numeric: tabular-nums; }

.quiz-finish {
  margin-top: 32px;
  padding: 28px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px dashed var(--light-border);
  text-align: center;
}
.quiz-finish.ready { border-style: solid; border-color: var(--accent); background: rgba(26, 122, 109, 0.04); }
.quiz-finish-btn {
  padding: 16px 32px; border-radius: 999px;
  background: var(--dark); color: var(--light);
  border: none; cursor: pointer;
  font-family: var(--sans); font-weight: 700; font-size: 14px;
  letter-spacing: 0.04em;
  transition: transform 200ms var(--ease), background 200ms var(--ease), box-shadow 200ms var(--ease), opacity 200ms var(--ease);
  box-shadow: 0 10px 24px -12px rgba(10, 31, 31, 0.3);
}
.quiz-finish-btn:disabled { opacity: 0.45; cursor: not-allowed; box-shadow: none; }
.quiz-finish.ready .quiz-finish-btn {
  background: var(--accent);
  opacity: 1;
  box-shadow: 0 14px 28px -10px rgba(26, 122, 109, 0.5);
  animation: pulseReady 1400ms var(--ease) 1;
}
.quiz-finish.ready .quiz-finish-btn:hover { transform: translateY(-2px); background: var(--dark); }
@keyframes pulseReady {
  0% { box-shadow: 0 0 0 0 rgba(26, 122, 109, 0.5); }
  70% { box-shadow: 0 0 0 14px rgba(26, 122, 109, 0); }
  100% { box-shadow: 0 14px 28px -10px rgba(26, 122, 109, 0.5); }
}
.quiz-finish-hint {
  margin-top: 14px;
  font-size: 12px; color: var(--muted-text);
  max-width: 360px; margin-left: auto; margin-right: auto;
  line-height: 1.5;
}

.result {
  text-align: center; padding: 48px 32px; border-radius: 24px;
  background: linear-gradient(165deg, var(--dark) 0%, var(--accent) 100%);
  color: var(--light); display: none; margin-top: 32px;
}
.result.shown { display: block; animation: fadeUp 600ms var(--ease) both; }
.result .score { font-family: var(--serif); font-size: 56px; font-weight: 600; letter-spacing: -0.025em; margin-bottom: 4px; }
.result .pct { font-size: 13px; opacity: 0.65; letter-spacing: 0.16em; margin-bottom: 22px; font-weight: 700; }
.result h3 { font-family: var(--serif); font-size: 24px; font-weight: 600; margin-bottom: 8px; letter-spacing: -0.01em; }
.result .msg { font-size: 14px; opacity: 0.85; line-height: 1.5; max-width: 400px; margin: 0 auto; }
.result .xp-awarded {
  display: inline-flex; align-items: center; gap: 8px; margin-top: 20px;
  padding: 8px 18px; border-radius: 999px;
  background: rgba(239, 248, 246, 0.12); font-size: 13px; font-weight: 700;
  letter-spacing: 0.04em; text-transform: uppercase;
}

/* footer */
.site-foot {
  max-width: var(--max-wide); margin: 0 auto;
  padding: 48px 28px;
  border-top: 1px solid var(--light-border);
  display: flex; justify-content: space-between; align-items: center;
  font-size: 12px; color: var(--muted-text);
  flex-wrap: wrap; gap: 16px;
}
.site-foot a { color: var(--muted-text); }
.site-foot a:hover { color: var(--dark); }

/* ---------- mobile ---------- */
@media (max-width: 640px) {
  .nav-inner { padding: 12px 16px; gap: 8px; }
  .nav-right { gap: 8px; }
  .nav-right > a:not(.cta-sm) { display: none; }
  .stat-pill { padding: 5px 10px; font-size: 11px; }
  .lesson-wrap { padding: 28px 20px 80px; }
  .lesson p, .lesson li { font-size: 16px; }
  .lesson-hero { margin: 0 -20px 28px; padding: 48px 24px; }
  .hero { padding: 64px 20px 48px; }
  .hero h1 { font-size: 40px; }
  .hero p.lead { font-size: 17px; }
  .curriculum { padding: 0 20px; }
  .chapter-grid { grid-template-columns: 1fr; }
  .lesson-foot { flex-direction: column; }
  .chapter-hero { padding: 48px 20px 16px; }
  .chapter-progress-box { padding: 0 20px; }
  .chapter-foot { flex-direction: column; padding: 0 20px; }
  .quiz-wrap { padding: 36px 20px 80px; }
  .question { padding: 24px; }
  .stat-card { padding: 28px 22px; }
  .stat-card .big { font-size: 56px; }
  .dashboard { padding: 24px 20px 0; }
  .dash-card { padding: 24px; }
}