/* Geometry lessons are static evidence views: no script, form, tracker, or
   runtime fetch is required to read the complete human account. */

:root {
  /* These ink colors are deliberately darker than the estate's decorative
     terracotta/green/gold tokens. Each clears WCAG AA for small text on the
     exact dawn surfaces used below; color remains decorative, never the only
     link or evidence-kind affordance. */
  --geometry-accent-readable: #873017;
  --geometry-fact-readable: #32703f;
  --geometry-inference-readable: #775a12;
  --geometry-analogy-readable: #3d5a8a;
  --geometry-stage-number-bg: #f0dccd;
  --geometry-landscape-bg: #f3ecdf;
  --geometry-basin-bg: #efe6d4;
  --geometry-form-two-bg: #e4e5e8;
}

.estate-strip a.here,
.topnav .brand-text > span,
.topnav .nav-actions a.active,
.geometry-hero .eyebrow {
  color: var(--geometry-accent-readable);
}

.geometry-hero .eyebrow::before {
  background: var(--geometry-accent-readable);
}

.geometry-hero h1 em {
  background: none;
  background-clip: border-box;
  -webkit-background-clip: border-box;
  color: var(--geometry-accent-readable);
  -webkit-text-fill-color: currentColor;
}

.topnav .nav-cta,
.topnav .nav-cta:hover {
  background: var(--geometry-accent-readable);
  color: #faf5ec !important;
}

.estate-strip a:focus-visible,
.topnav a:focus-visible,
.geometry-shell a:focus-visible,
.site-footer a:focus-visible {
  outline: 3px solid var(--geometry-accent-readable);
  outline-offset: 3px;
}

.geometry-shell {
  max-width: 1180px;
  margin: 0 auto;
  padding: calc(var(--nav-height) + 2rem) 1.75rem 3rem;
}

.geometry-hero {
  position: relative;
  max-width: 940px;
  padding: clamp(2rem, 6vw, 4.5rem) 0 2.5rem;
  overflow: clip;
}

.geometry-hero::before {
  display: none;
}

.geometry-hero h1 {
  max-width: 860px;
}

.geometry-hero .lede {
  max-width: 800px;
  font-size: clamp(1.08rem, 2vw, 1.3rem);
}

.geometry-links,
.geometry-stats,
.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin: 1.25rem 0 0;
}

.geometry-stats {
  padding: 0;
  list-style: none;
}

.geometry-links a,
.stat-chip,
.evidence-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  border: 1px solid var(--border-bright);
  border-radius: var(--r-pill);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  padding: 0.38rem 0.72rem;
  font-family: var(--mono);
  font-size: 0.7rem;
  line-height: 1.35;
}

.geometry-links a:hover {
  border-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 7%, var(--surface));
}

.stat-chip {
  margin: 0;
  color: var(--text-muted);
}

.geometry-content p a,
.source-list a {
  color: var(--geometry-accent-readable);
  text-decoration-line: underline;
  text-decoration-thickness: 0.09em;
  text-underline-offset: 0.16em;
  text-decoration-skip-ink: auto;
}

.geometry-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 250px;
  gap: clamp(2rem, 5vw, 4rem);
  align-items: start;
}

.geometry-content {
  min-width: 0;
  max-width: 840px;
}

.geometry-content h2 {
  margin-top: 4.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.geometry-content h2:first-child {
  margin-top: 0;
}

.lesson-nav {
  position: sticky;
  top: calc(var(--nav-height) + 1rem);
  padding: 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  box-shadow: var(--shadow-card);
}

.lesson-nav h2 {
  margin: 0 0 0.75rem;
  padding: 0;
  border: 0;
  font-family: var(--mono);
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-dim);
}

.lesson-nav ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

.lesson-nav li {
  margin: 0;
}

.lesson-nav a {
  display: block;
  padding: 0.42rem 0.55rem;
  border-left: 2px solid transparent;
  border-radius: var(--r-sm);
  color: var(--text-muted);
  font-size: 0.82rem;
}

.lesson-nav a:hover {
  color: var(--accent-text);
  border-left-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 6%, transparent);
}

.core-account {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.9rem;
  margin: 1.5rem 0;
  counter-reset: core-step;
}

.core-card {
  position: relative;
  min-height: 180px;
  padding: 1.15rem;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: var(--surface);
  box-shadow: var(--shadow-card);
  counter-increment: core-step;
}

.core-card::before {
  content: "0" counter(core-step);
  display: block;
  margin-bottom: 0.8rem;
  font-family: var(--mono);
  font-size: 0.67rem;
  letter-spacing: 0.12em;
  color: var(--accent-text);
}

.core-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1rem;
}

.core-card p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.landscape {
  margin: 1.5rem 0;
  padding: clamp(1rem, 3vw, 1.75rem);
  border: 1px solid var(--border-bright);
  border-radius: var(--r-xl);
  background: var(--geometry-landscape-bg);
  box-shadow: var(--shadow-card);
}

.landscape svg {
  width: 100%;
  height: auto;
  overflow: visible;
}

.landscape .basin {
  fill: var(--geometry-basin-bg);
  stroke: var(--border-bright);
  stroke-width: 2;
}

.landscape .basin.form-two {
  fill: var(--geometry-form-two-bg);
  stroke: color-mix(in srgb, var(--blue) 55%, var(--border));
}

.landscape .route {
  fill: none;
  stroke: var(--text-muted);
  stroke-width: 3;
}

.landscape .route.rare {
  stroke-dasharray: 8 7;
}

.landscape .route.seeded {
  stroke: var(--accent);
  stroke-width: 4;
}

.landscape #arrow-neutral path {
  fill: var(--text-muted);
}

.landscape #arrow-accent path {
  fill: var(--accent);
}

.landscape .node-title {
  fill: var(--text);
  font-family: var(--sans);
  font-size: 17px;
  font-weight: 700;
}

.landscape .node-note,
.landscape .route-note {
  fill: var(--text-muted);
  font-family: var(--mono);
  font-size: 12px;
}

.landscape figcaption {
  margin-top: 1rem;
  color: var(--text-muted);
  font-size: 0.82rem;
}

.equation {
  display: block;
  margin: 1rem 0;
  padding: 0.9rem 1rem;
  overflow-wrap: anywhere;
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  background: var(--code-bg);
  color: var(--text-muted);
  font-family: var(--mono);
  font-size: 0.78rem;
}

.stage-list {
  display: grid;
  gap: 0.85rem;
  margin: 1.5rem 0;
}

.stage {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 1rem;
  padding: 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
}

.stage-number {
  width: 42px;
  height: 42px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--geometry-stage-number-bg);
  color: var(--geometry-accent-readable);
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 700;
}

.stage h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
}

.stage p {
  margin: 0;
  color: var(--text-muted);
}

.claim-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
  margin: 1.5rem 0;
}

.claim-card {
  padding: 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--r-lg);
  background: var(--surface);
}

.claim-card h3 {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 0.6rem;
  font-family: var(--mono);
  font-size: 0.78rem;
}

.claim-card p {
  margin-bottom: 0.65rem;
}

.claim-card .conditions {
  margin: 0;
  padding-top: 0.65rem;
  border-top: 1px solid var(--border);
  color: var(--text-dim);
  font-size: 0.76rem;
}

.evidence-badge {
  padding: 0.18rem 0.48rem;
  font-size: 0.58rem;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.evidence-badge.fact {
  color: var(--geometry-fact-readable);
  border-color: color-mix(in srgb, var(--green) 45%, var(--border));
}

.evidence-badge.inference {
  color: var(--geometry-inference-readable);
  border-color: color-mix(in srgb, var(--gold) 45%, var(--border));
}

.evidence-badge.analogy {
  color: var(--geometry-analogy-readable);
  border-color: color-mix(in srgb, var(--blue) 45%, var(--border));
}

.question-grid,
.uncertainty-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
  margin: 1.5rem 0;
}

.question,
.uncertainty {
  padding: 1.1rem;
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--r-lg) var(--r-lg) 0;
  background: color-mix(in srgb, var(--accent) 5%, var(--surface));
}

.question h3,
.uncertainty h3 {
  margin: 0 0 0.45rem;
  font-size: 0.98rem;
}

.question p,
.uncertainty p {
  margin: 0;
  color: var(--text-muted);
}

.uncertainty {
  border-left-color: var(--gold);
  background: color-mix(in srgb, var(--gold) 5%, var(--surface));
}

.source-list {
  margin-left: 0;
  list-style: none;
  counter-reset: source;
}

.source-list li {
  position: relative;
  margin: 0;
  padding: 0.8rem 0 0.8rem 2.7rem;
  border-bottom: 1px solid var(--border);
  color: var(--text-muted);
  counter-increment: source;
}

.source-list li::before {
  content: "S" counter(source, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 0.92rem;
  font-family: var(--mono);
  font-size: 0.64rem;
  color: var(--accent-text);
}

.source-list a {
  overflow-wrap: anywhere;
}

.provenance-box {
  margin: 1.5rem 0;
  padding: 1.15rem;
  border: 1px solid var(--border-bright);
  border-radius: var(--r-lg);
  background: var(--code-bg);
}

.provenance-box dl {
  display: grid;
  grid-template-columns: minmax(9rem, 0.35fr) minmax(0, 1fr);
  gap: 0.45rem 1rem;
  margin: 0;
}

.provenance-box dt {
  color: var(--text-dim);
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.provenance-box dd {
  min-width: 0;
  margin: 0;
  color: var(--text-muted);
  font-family: var(--mono);
  font-size: 0.72rem;
  overflow-wrap: anywhere;
}

.boundary-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
  margin: 1.25rem 0;
  padding: 0;
  list-style: none;
}

.boundary-list li {
  margin: 0;
  padding: 0.9rem;
  border: 1px solid var(--border);
  border-radius: var(--r-md);
  color: var(--text-muted);
  background: color-mix(in srgb, var(--surface) 82%, transparent);
}

.footer-mark {
  width: 14px;
  height: 14px;
  border-width: 1.5px;
}

@media (max-width: 900px) {
  .geometry-layout {
    grid-template-columns: 1fr;
  }

  .lesson-nav {
    position: static;
    order: -1;
  }

  .lesson-nav ol {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
  }
}

@media (max-width: 680px) {
  .geometry-shell {
    padding-inline: 1.1rem;
  }

  .core-account,
  .claim-grid,
  .question-grid,
  .uncertainty-grid,
  .boundary-list {
    grid-template-columns: 1fr;
  }

  .stage {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 0.75rem;
  }

  .stage-number {
    width: 36px;
    height: 36px;
  }

  .provenance-box dl {
    grid-template-columns: 1fr;
  }

  .provenance-box dd {
    margin-bottom: 0.55rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}

@media print {
  .estate-strip,
  .topnav,
  .lesson-nav,
  .geometry-links,
  .site-footer {
    display: none;
  }

  .geometry-shell {
    max-width: none;
    padding: 0;
  }

  .geometry-layout {
    display: block;
  }

  .core-card,
  .stage,
  .claim-card,
  .landscape {
    break-inside: avoid;
    box-shadow: none;
  }
}