:root {
  --paper: #f7f3ea;
  --paper-deep: #ede5d7;
  --ink: #173b35;
  --ink-soft: #476660;
  --apricot: #f2b36d;
  --mint: #8ee1bf;
  --coral: #d55a44;
  --line: rgba(23, 59, 53, 0.2);
  --white: #fffdfa;
  --serif: Georgia, 'Times New Roman', serif;
  --sans: Arial, Helvetica, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.62;
}
body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  content: '';
  opacity: 0.16;
  pointer-events: none;
  background-image: radial-gradient(var(--ink) 0.55px, transparent 0.65px);
  background-size: 11px 11px;
}
a { color: inherit; text-decoration-thickness: 1.5px; text-underline-offset: 3px; }
a:hover { color: var(--coral); }
button { font: inherit; }

.skip-link {
  position: fixed;
  z-index: 30;
  top: -100px;
  left: 1rem;
  padding: 0.6rem 0.9rem;
  background: var(--ink);
  color: var(--white);
}
.skip-link:focus { top: 1rem; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0.85rem clamp(1.25rem, 4vw, 4.5rem);
  border-bottom: 1px solid var(--line);
  background: rgba(247, 243, 234, 0.94);
  backdrop-filter: blur(12px);
}
.brand { display: inline-flex; align-items: center; gap: 0.65rem; text-decoration: none; line-height: 1; }
.brand:hover { color: var(--ink); }
.brand-mark {
  display: grid;
  width: 38px;
  height: 38px;
  place-items: center;
  border-radius: 50% 50% 50% 8%;
  color: var(--ink);
  background: var(--mint);
  font-family: var(--serif);
  font-weight: 700;
  font-size: 1.45rem;
  transform: rotate(-16deg);
}
.brand strong { display: block; font-size: 0.88rem; letter-spacing: 0.13em; }
.brand small { display: block; margin-top: 0.24rem; color: var(--ink-soft); font-size: 0.64rem; letter-spacing: 0.06em; text-transform: uppercase; }
.site-nav { display: flex; gap: clamp(0.85rem, 2.1vw, 2rem); align-items: center; }
.site-nav a { font-size: 0.78rem; font-weight: 700; letter-spacing: 0.04em; text-decoration: none; }
.site-nav a::after { display: block; width: 0; height: 2px; margin-top: 3px; content: ''; background: var(--coral); transition: width 180ms ease; }
.site-nav a:hover::after, .site-nav a.is-active::after { width: 100%; }
.menu-toggle { display: none; border: 0; background: transparent; color: var(--ink); }

.hero {
  display: grid;
  grid-template-columns: minmax(54px, 0.15fr) minmax(0, 1.15fr) minmax(280px, 0.7fr);
  min-height: 570px;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}
.hero-number {
  display: flex;
  justify-content: center;
  align-items: flex-end;
  padding: 0 0 1.85rem;
  border-right: 1px solid var(--line);
  background: var(--apricot);
  font-family: var(--serif);
  font-size: clamp(2.1rem, 5vw, 4.8rem);
  font-weight: 700;
  line-height: 1;
  writing-mode: vertical-rl;
  transform: rotate(180deg);
}
.hero-copy { display: flex; flex-direction: column; justify-content: center; padding: clamp(3.2rem, 7vw, 6.5rem) clamp(1.4rem, 5.5vw, 6.5rem); }
.eyebrow, .small-caps { margin: 0 0 0.75rem; color: var(--ink-soft); font-size: 0.7rem; font-weight: 700; letter-spacing: 0.14em; line-height: 1.35; text-transform: uppercase; }
.hero h1, h2, h3 { text-wrap: balance; }
.hero h1 { max-width: 780px; margin: 0; font-family: var(--serif); font-size: clamp(3.1rem, 6.6vw, 6.5rem); line-height: 0.92; letter-spacing: -0.058em; }
.hero-lede { max-width: 650px; margin: 1.65rem 0 0; font-size: clamp(1rem, 1.35vw, 1.25rem); line-height: 1.56; }
.hero-meta { display: flex; flex-wrap: wrap; gap: 0.55rem; margin-top: 1.8rem; color: var(--ink-soft); font-size: 0.76rem; font-weight: 700; }
.hero-meta a { color: var(--ink); }
.hero-art {
  position: relative;
  min-height: 400px;
  margin: 0;
  overflow: hidden;
  border-left: 1px solid var(--line);
  isolation: isolate;
  background: linear-gradient(145deg, #a7ebcf 0%, #8ee1bf 56%, #f2b36d 56%, #f2b36d 100%);
}
.hero-art::before, .hero-art::after { position: absolute; z-index: -1; content: ''; border: 1px solid rgba(23, 59, 53, 0.24); border-radius: 50%; }
.hero-art::before { width: 360px; height: 360px; top: 16%; left: 10%; }
.hero-art::after { width: 500px; height: 500px; top: -12%; left: -31%; }
.hero-art img { position: absolute; z-index: 2; inset: 0; width: 100%; height: 100%; object-fit: cover; mix-blend-mode: multiply; opacity: 0.88; transition: opacity 180ms ease; }
.hero-art img.is-hidden { opacity: 0; pointer-events: none; }
.hero-art figcaption { position: absolute; z-index: 3; right: 1rem; bottom: 1rem; width: min-content; color: var(--ink); font-size: 0.68rem; font-weight: 700; line-height: 1.35; text-transform: uppercase; }
.art-orbit, .art-ring, .art-leaf { position: absolute; z-index: 1; display: block; }
.orbit-one { top: 30%; left: 33%; width: 156px; height: 156px; border: 14px solid var(--ink); border-radius: 50%; }
.orbit-two { top: 14%; left: 54%; width: 78px; height: 78px; border: 12px solid var(--coral); border-radius: 50%; }
.ring-one { bottom: 16%; left: 20%; width: 120px; height: 44px; border: 12px solid var(--white); border-radius: 50%; transform: rotate(-38deg); }
.ring-two { right: 11%; bottom: 26%; width: 52px; height: 152px; border: 10px solid var(--ink); border-radius: 50%; transform: rotate(37deg); }
.art-leaf { width: 95px; height: 51px; background: var(--coral); border-radius: 90% 8% 90% 8%; transform: rotate(-36deg); }
.leaf-one { top: 20%; left: 16%; }
.leaf-two { right: 18%; bottom: 19%; background: var(--white); transform: rotate(34deg); }

.quick-read {
  display: grid;
  grid-template-columns: 0.44fr 1.26fr 0.7fr;
  gap: 2rem;
  margin: 0 clamp(1.25rem, 8vw, 10rem);
  padding: 2.8rem 0;
  border-bottom: 1px solid var(--line);
}
.quick-label { align-self: start; padding-top: 0.3rem; font-size: 0.7rem; font-weight: 800; letter-spacing: 0.14em; }
.quick-read h2 { margin: 0 0 0.55rem; font-family: var(--serif); font-size: 1.95rem; letter-spacing: -0.035em; }
.quick-read p { margin: 0; }
.quick-aside { padding-left: 1.4rem; border-left: 3px solid var(--mint); }
.quick-aside .small-caps { margin-bottom: 0.35rem; }
.quick-aside p { font-size: 0.93rem; line-height: 1.5; }
.citation { display: inline-grid; min-width: 28px; height: 22px; margin: 0 0.1rem; padding: 0 0.35rem; place-items: center; border-radius: 999px; background: var(--mint); color: var(--ink); font-size: 0.66rem; font-weight: 800; letter-spacing: 0.04em; line-height: 1; text-decoration: none; vertical-align: 0.15em; }
.citation:hover { background: var(--coral); color: var(--white); }
.static-citation { pointer-events: none; }

.chapter-section, .bibliography-section { display: grid; grid-template-columns: minmax(120px, 0.25fr) minmax(0, 1fr); }
.chapter-rail { position: relative; padding: 4.7rem clamp(1.1rem, 3vw, 3.8rem); border-right: 1px solid var(--line); background: var(--apricot); }
.chapter-rail span { display: block; font-family: var(--serif); font-size: clamp(3.5rem, 6vw, 6.2rem); font-weight: 700; line-height: 0.8; letter-spacing: -0.08em; }
.chapter-rail p { margin: 1.5rem 0 0; font-size: 0.68rem; font-weight: 800; letter-spacing: 0.09em; line-height: 1.55; }
.chapter-content, .bibliography-content { max-width: 1180px; padding: clamp(4.7rem, 8vw, 8rem) clamp(1.5rem, 9vw, 11rem); }
.section-heading { max-width: 800px; }
h2 { margin: 0; font-family: var(--serif); font-size: clamp(2.8rem, 5vw, 5.2rem); line-height: 0.94; letter-spacing: -0.06em; }
.section-intro { margin: 1.35rem 0 0; font-size: clamp(1.06rem, 1.5vw, 1.28rem); line-height: 1.58; }
.reason { display: grid; grid-template-columns: 86px minmax(0, 1fr); gap: clamp(1rem, 2.5vw, 2.2rem); max-width: 860px; padding: 2.55rem 0; border-top: 1px solid var(--line); }
.section-heading + .reason { margin-top: 4.1rem; }
.reason-index { padding-top: 0.23rem; color: var(--ink-soft); font-size: 0.72rem; font-weight: 800; letter-spacing: 0.1em; }
.reason h3 { margin: 0 0 0.55rem; font-family: var(--serif); font-size: clamp(1.7rem, 2.4vw, 2.3rem); line-height: 1.04; letter-spacing: -0.04em; }
.reason p { margin: 0; }
.reason-highlight { position: relative; margin-left: clamp(-0.7rem, -2vw, -2rem); padding-right: clamp(0.8rem, 2.2vw, 2.4rem); padding-left: clamp(0.7rem, 2vw, 2rem); background: rgba(142, 225, 191, 0.3); }
.note { margin-top: 1.1rem !important; padding: 0.9rem 1rem; border-left: 3px solid var(--coral); background: rgba(255, 253, 250, 0.65); font-size: 0.9rem; line-height: 1.52; }
.takeaway { display: grid; grid-template-columns: 64px minmax(0, 1fr); gap: 1rem; max-width: 860px; margin-top: 2.6rem; padding: 2rem 0 0; border-top: 4px solid var(--ink); }
.takeaway-mark { font-family: var(--serif); font-size: 3.1rem; line-height: 0.8; }
.takeaway p:last-child { margin: 0; font-size: 1.16rem; line-height: 1.52; }

.sources-section { display: grid; grid-template-columns: minmax(0, 0.75fr) minmax(0, 1.25fr); gap: clamp(2rem, 8vw, 9rem); padding: clamp(4.5rem, 8vw, 8rem) clamp(1.5rem, 10vw, 12rem); background: var(--ink); color: var(--white); }
.sources-section .eyebrow { color: var(--mint); }
.sources-section h2 { max-width: 590px; }
.sources-explainer { max-width: 620px; padding-top: 1rem; font-size: 1.06rem; }
.source-legend { display: flex; flex-wrap: wrap; gap: 1rem 1.25rem; margin-top: 1.8rem; font-size: 0.78rem; font-weight: 700; }
.legend-dot { display: inline-block; width: 9px; height: 9px; margin-right: 0.35rem; border-radius: 50%; }
.legend-dot.model { background: var(--mint); }.legend-dot.public { background: var(--apricot); }.legend-dot.academic { background: var(--coral); }

.bibliography-rail { background: var(--mint); }
.bibliography-list { max-width: 900px; margin: 4rem 0 0; padding: 0; list-style: none; }
.source-entry { display: grid; grid-template-columns: 64px minmax(0, 1fr); gap: 1rem; padding: 1.8rem 0; border-top: 1px solid var(--line); scroll-margin-top: 100px; }
.source-entry:last-child { border-bottom: 1px solid var(--line); }
.source-entry:target { margin: 0 -1.2rem; padding: 1.8rem 1.2rem; background: rgba(242, 179, 109, 0.24); }
.source-code { align-self: start; display: grid; width: 42px; height: 42px; place-items: center; border: 1px solid var(--ink); border-radius: 50%; font-size: 0.73rem; font-weight: 800; }
.source-type { margin: 0 0 0.42rem; font-size: 0.64rem; font-weight: 800; letter-spacing: 0.11em; line-height: 1.35; }
.source-model .source-type { color: #188f6e; }.source-public .source-type { color: #a64f17; }.source-academic .source-type { color: #b14135; }
.source-entry h3 { margin: 0; font-family: var(--serif); font-size: clamp(1.18rem, 1.85vw, 1.55rem); line-height: 1.16; letter-spacing: -0.025em; }
.source-entry p:not(.source-type) { max-width: 700px; margin: 0.65rem 0 0; color: var(--ink-soft); font-size: 0.93rem; line-height: 1.55; }
.source-entry a { display: inline-block; margin-top: 0.75rem; color: var(--ink); font-size: 0.78rem; font-weight: 800; text-decoration-color: var(--coral); text-decoration-thickness: 2px; }

.site-footer { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1.5rem clamp(1.25rem, 4vw, 4.5rem); background: var(--paper-deep); color: var(--ink-soft); font-size: 0.76rem; }
.site-footer p { margin: 0; }.site-footer a { color: var(--ink); font-weight: 700; }
.back-to-top { position: fixed; z-index: 11; right: 1.2rem; bottom: 1.2rem; display: grid; width: 42px; height: 42px; place-items: center; border: 1px solid var(--ink); border-radius: 50%; background: var(--paper); color: var(--ink); cursor: pointer; opacity: 0; pointer-events: none; transform: translateY(12px); transition: opacity 180ms ease, transform 180ms ease, background 180ms ease; }
.back-to-top.is-visible { opacity: 1; pointer-events: auto; transform: translateY(0); }.back-to-top:hover { background: var(--mint); }

@media (max-width: 800px) {
  .site-header { min-height: 65px; }.menu-toggle { display: inline-grid; width: 39px; height: 39px; place-items: center; border: 1px solid var(--line); border-radius: 50%; cursor: pointer; }.menu-icon, .menu-icon::before, .menu-icon::after { display: block; width: 16px; height: 1.5px; background: currentColor; content: ''; }.menu-icon { position: relative; }.menu-icon::before { position: absolute; top: -5px; }.menu-icon::after { position: absolute; top: 5px; }
  .site-nav { position: absolute; top: 100%; right: 0.85rem; display: none; width: min(250px, calc(100vw - 1.7rem)); padding: 0.7rem; border: 1px solid var(--line); background: var(--paper); box-shadow: 0 15px 35px rgba(23, 59, 53, 0.15); }.site-nav.is-open { display: grid; gap: 0; }.site-nav a { padding: 0.75rem; }.site-nav a::after { display: none; }
  .hero { grid-template-columns: 58px minmax(0, 1fr); min-height: unset; }.hero-copy { min-height: 495px; padding-right: 1.6rem; }.hero-art { grid-column: 1 / -1; min-height: 285px; border-top: 1px solid var(--line); border-left: 0; }.hero-number { padding-bottom: 1rem; }.hero h1 { font-size: clamp(3rem, 10.5vw, 5.5rem); }
  .quick-read { grid-template-columns: 1fr; gap: 1rem; margin: 0 1.5rem; }.quick-aside { margin-top: 0.8rem; }.chapter-section, .bibliography-section { grid-template-columns: 1fr; }.chapter-rail { display: flex; align-items: center; gap: 1rem; padding: 1rem 1.5rem; border-right: 0; border-bottom: 1px solid var(--line); }.chapter-rail span { font-size: 2.7rem; }.chapter-rail p { margin: 0; }.chapter-content, .bibliography-content { padding: 4rem 1.5rem; }.reason { grid-template-columns: 40px minmax(0, 1fr); gap: 0.8rem; }.reason-highlight { margin-left: -0.75rem; }.sources-section { grid-template-columns: 1fr; gap: 2rem; padding: 4rem 1.5rem; }.bibliography-list { margin-top: 3rem; }.source-entry { grid-template-columns: 47px minmax(0, 1fr); gap: 0.75rem; }.source-code { width: 36px; height: 36px; }.site-footer { align-items: flex-start; flex-direction: column; }
}

@media (max-width: 410px) { .hero-copy { min-height: 450px; }.hero-number { padding-bottom: 0.55rem; }.dot-separator { display: none; }.hero-meta { flex-direction: column; }.takeaway { grid-template-columns: 45px minmax(0, 1fr); }.takeaway-mark { font-size: 2.4rem; } }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; } }