:root {
  --ink: #071716;
  --ink-soft: #19302d;
  --paper: #f4f1e8;
  --paper-deep: #e8e3d6;
  --mint: #7de2c2;
  --mint-bright: #a8f1d9;
  --line-dark: rgba(7, 23, 22, 0.2);
  --line-light: rgba(244, 241, 232, 0.2);
  --muted: #63716e;
  --max: 1240px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
}
body.menu-open { overflow: hidden; }
a { color: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
.skip-link { position: fixed; top: 0; left: 1rem; z-index: 100; transform: translateY(-120%); background: var(--mint); color: var(--ink); padding: .7rem 1rem; font-weight: 800; }
.skip-link:focus { transform: translateY(0); }
.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: fixed;
  z-index: 50;
  top: 0;
  left: 0;
  right: 0;
  min-height: 86px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem max(2rem, calc((100vw - var(--max)) / 2));
  color: var(--paper);
  border-bottom: 1px solid rgba(244, 241, 232, .14);
  transition: background .25s ease, min-height .25s ease;
}
.site-header.scrolled { min-height: 70px; background: rgba(7, 23, 22, .94); backdrop-filter: blur(16px); }
.brand { display: inline-flex; gap: .75rem; align-items: center; color: inherit; text-decoration: none; font-size: .72rem; font-weight: 800; letter-spacing: .07em; line-height: 1.15; text-transform: uppercase; }
.brand-mark { width: 36px; height: 36px; display: grid; place-items: center; border: 1px solid var(--mint); transform: rotate(45deg); }
.brand-mark span { width: 10px; height: 10px; background: var(--mint); }
.site-nav { display: flex; align-items: center; gap: 2rem; }
.site-nav a { position: relative; text-decoration: none; font-size: .8rem; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; }
.site-nav a:not(.nav-cta)::after { content: ""; position: absolute; left: 0; right: 100%; bottom: -.35rem; height: 1px; background: var(--mint); transition: right .2s ease; }
.site-nav a:hover::after, .site-nav a:focus-visible::after { right: 0; }
.nav-cta { border: 1px solid var(--mint); padding: .65rem 1rem; color: var(--mint); }
.menu-toggle { display: none; background: transparent; border: 0; width: 44px; height: 44px; padding: 10px; }
.menu-toggle > span:not(.sr-only) { display: block; height: 1px; background: var(--paper); margin: 8px 0; transition: transform .2s ease; }

.hero { position: relative; min-height: 100svh; background: var(--ink); color: var(--paper); overflow: hidden; padding: 10rem max(2rem, calc((100vw - var(--max)) / 2)) 3rem; display: grid; grid-template-columns: 1.1fr .9fr; gap: 4rem; align-items: center; }
.hero::before { content: ""; position: absolute; inset: 0; opacity: .13; background-image: linear-gradient(rgba(125,226,194,.35) 1px, transparent 1px), linear-gradient(90deg, rgba(125,226,194,.35) 1px, transparent 1px); background-size: 64px 64px; mask-image: linear-gradient(to right, #000, transparent 78%); }
.hero-copy, .hero-system, .hero-footnote { position: relative; z-index: 1; }
.eyebrow { display: flex; align-items: center; justify-content: space-between; max-width: 560px; padding-bottom: .75rem; border-bottom: 1px solid var(--line-light); text-transform: uppercase; letter-spacing: .13em; font-size: .72rem; font-weight: 800; color: var(--mint); }
h1, h2, h3, p { margin-top: 0; }
h1, h2 { letter-spacing: -.055em; line-height: .95; }
h1 { margin: 2rem 0; font-size: clamp(3.8rem, 7vw, 7.2rem); font-weight: 680; }
h1 em, h2 em { color: var(--mint); font-family: Georgia, "Times New Roman", serif; font-weight: 400; }
.hero-lede { max-width: 660px; color: rgba(244,241,232,.72); font-size: clamp(1.1rem, 1.55vw, 1.35rem); line-height: 1.55; }
.hero-actions { display: flex; align-items: center; gap: 2rem; margin-top: 2.25rem; }
.button { display: inline-flex; align-items: center; justify-content: space-between; min-width: 210px; gap: 2rem; padding: 1rem 1.15rem; text-decoration: none; text-transform: uppercase; letter-spacing: .07em; font-size: .78rem; font-weight: 850; transition: transform .2s ease, background .2s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--mint); color: var(--ink); }
.button-primary:hover { background: var(--mint-bright); }
.text-link { text-underline-offset: .35rem; text-decoration-color: rgba(244,241,232,.35); font-size: .78rem; text-transform: uppercase; letter-spacing: .08em; font-weight: 800; }
.hero-system { width: min(100%, 540px); aspect-ratio: 1; justify-self: end; }
.system-orbit { position: absolute; border: 1px solid rgba(125,226,194,.25); border-radius: 50%; }
.orbit-one { inset: 11%; animation: spin 24s linear infinite; }
.orbit-one::before, .orbit-two::before { content: ""; position: absolute; width: 8px; height: 8px; background: var(--mint); border-radius: 50%; top: -4px; left: 50%; box-shadow: 0 0 20px var(--mint); }
.orbit-two { inset: 26%; animation: spin 17s linear infinite reverse; }
.system-node { position: absolute; display: flex; flex-direction: column; padding: .7rem; text-transform: uppercase; font-size: .66rem; font-weight: 800; letter-spacing: .09em; background: var(--ink); border: 1px solid rgba(244,241,232,.3); }
.system-node span { color: var(--mint); }
.system-node-core { inset: 35%; align-items: center; justify-content: center; text-align: center; border-color: var(--mint); }
.system-node-core strong { font-size: 1.2rem; letter-spacing: .12em; }
.system-node-core small { margin-top: .4rem; color: rgba(244,241,232,.5); font-size: .55rem; }
.system-node-a { top: 5%; left: 15%; }
.system-node-b { top: 24%; right: 0; }
.system-node-c { bottom: 8%; right: 14%; }
.system-node-d { bottom: 19%; left: 0; }
.hero-footnote { position: absolute; left: max(2rem, calc((100vw - var(--max)) / 2)); right: max(2rem, calc((100vw - var(--max)) / 2)); bottom: 2rem; display: flex; gap: 1rem; color: rgba(244,241,232,.45); font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; }
.hero-footnote strong { color: rgba(244,241,232,.72); }

.section-pad { padding: clamp(5rem, 10vw, 9rem) max(2rem, calc((100vw - var(--max)) / 2)); }
.section-index { margin-bottom: 3rem; color: var(--muted); font-size: .7rem; font-weight: 800; letter-spacing: .13em; text-transform: uppercase; }
.statement-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8vw; }
.statement h2, .section-heading h2, .failure h2 { font-size: clamp(2.8rem, 5.2vw, 5.5rem); font-weight: 620; }
.statement-grid > div { border-top: 1px solid var(--line-dark); padding-top: 1.5rem; color: var(--muted); }
.large-copy { color: var(--ink); font-size: 1.35rem; line-height: 1.45; }
.section-heading { display: grid; grid-template-columns: 1fr 2fr 1fr; align-items: end; gap: 3rem; margin-bottom: 4rem; }
.section-heading .section-index { align-self: start; }
.section-heading h2 { margin-bottom: 0; }
.section-heading > p:last-child { color: var(--muted); }
.model { background: var(--paper-deep); }
.model-layout { display: grid; grid-template-columns: .9fr 1.1fr; min-height: 520px; border: 1px solid var(--line-dark); }
.model-tabs { display: grid; }
.model-tab { display: grid; grid-template-columns: 3rem 1fr; grid-template-rows: auto auto; text-align: left; padding: 1.4rem; color: var(--ink); background: transparent; border: 0; border-bottom: 1px solid var(--line-dark); cursor: pointer; }
.model-tab:last-child { border-bottom: 0; }
.model-tab span { grid-row: 1 / 3; color: var(--muted); font-size: .7rem; }
.model-tab strong { font-size: 1.15rem; }
.model-tab small { color: var(--muted); }
.model-tab.active { background: var(--mint); }
.model-tab.active span, .model-tab.active small { color: var(--ink-soft); }
.model-tab:focus-visible { outline: 3px solid var(--ink); outline-offset: -3px; }
.model-panel { display: flex; flex-direction: column; justify-content: center; padding: clamp(2rem, 6vw, 5rem); background: var(--ink); color: var(--paper); outline: 0; }
.panel-kicker { display: flex; justify-content: space-between; color: var(--mint); text-transform: uppercase; font-size: .7rem; font-weight: 800; letter-spacing: .12em; }
.model-panel h3 { max-width: 590px; margin: 3.2rem 0 1.4rem; font-size: clamp(2.4rem, 4vw, 4rem); line-height: 1; letter-spacing: -.04em; }
.model-panel > p { max-width: 620px; color: rgba(244,241,232,.68); font-size: 1.05rem; }
.model-panel dl { margin: 2.5rem 0 0; border-top: 1px solid var(--line-light); }
.model-panel dl div { display: grid; grid-template-columns: 1fr 2fr; padding: .8rem 0; border-bottom: 1px solid var(--line-light); }
.model-panel dt { color: rgba(244,241,232,.5); }
.model-panel dd { margin: 0; }

.assurance { background: var(--ink); color: var(--paper); }
.section-heading.light .section-index, .section-heading.light > p:last-child { color: rgba(244,241,232,.5); }
.assurance-loop { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line-light); border-left: 1px solid var(--line-light); }
.loop-step { position: relative; min-height: 320px; padding: 1.5rem; border-right: 1px solid var(--line-light); border-bottom: 1px solid var(--line-light); }
.loop-step::after { content: "→"; position: absolute; top: 1rem; right: 1rem; color: var(--mint); font-size: 1.3rem; }
.loop-step:last-child::after { content: "↺"; }
.loop-step > span { color: var(--mint); font-size: .7rem; }
.loop-step strong { display: block; margin-top: 7rem; font-size: 1.5rem; }
.loop-step p { margin-top: .7rem; color: rgba(244,241,232,.58); font-size: .92rem; }
.assurance-quote { display: grid; grid-template-columns: 2fr 1fr; gap: 3rem; align-items: end; padding-top: 5rem; }
.assurance-quote p { max-width: 870px; font-family: Georgia, "Times New Roman", serif; font-size: clamp(1.8rem, 3.5vw, 3.7rem); line-height: 1.18; }
.assurance-quote span { color: var(--mint); text-align: right; text-transform: uppercase; font-size: .7rem; font-weight: 800; letter-spacing: .12em; }

.failure { background: var(--mint); }
.failure .section-index { color: var(--ink-soft); }
.failure-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8vw; }
.failure-grid > div:first-child > p { max-width: 620px; }
.failure-register { border-top: 1px solid rgba(7,23,22,.4); }
.failure-register div { display: grid; grid-template-columns: 3.5rem 1fr; padding: 1.1rem 0; border-bottom: 1px solid rgba(7,23,22,.4); }
.failure-register span { grid-row: 1 / 3; font-size: .7rem; }
.failure-register small { color: var(--ink-soft); }

.research { background: var(--paper); }
.research-grid { display: grid; grid-template-columns: repeat(2, 1fr); border-top: 1px solid var(--line-dark); border-left: 1px solid var(--line-dark); }
.research-card { min-height: 330px; padding: 1.5rem; border-right: 1px solid var(--line-dark); border-bottom: 1px solid var(--line-dark); }
.research-card > span { color: var(--muted); font-size: .7rem; font-weight: 800; letter-spacing: .1em; }
.research-card h3 { margin: 4.5rem 0 1rem; font-size: 2rem; letter-spacing: -.035em; }
.research-card p { max-width: 480px; color: var(--muted); }
.research-card small { display: block; margin-top: 2.5rem; text-transform: uppercase; letter-spacing: .1em; font-weight: 800; color: var(--ink-soft); }

.participate { display: grid; grid-template-columns: 1.3fr .7fr; background: var(--ink-soft); color: var(--paper); }
.participate-copy, .participate-meta { padding: clamp(4rem, 8vw, 8rem) max(2rem, calc((100vw - var(--max)) / 2)); }
.participate-copy { padding-right: 7vw; }
.participate-copy .section-index { color: var(--mint); }
.participate-copy h2 { font-size: clamp(3.2rem, 6vw, 6rem); }
.participate-copy > p:not(.section-index) { max-width: 650px; color: rgba(244,241,232,.68); }
.button-light { margin-top: 1.5rem; background: var(--paper); color: var(--ink); }
.participate-meta { display: flex; flex-direction: column; justify-content: center; border-left: 1px solid var(--line-light); padding-left: 3rem; }
.participate-meta div { padding: 1.4rem 0; border-bottom: 1px solid var(--line-light); }
.participate-meta span, .participate-meta strong { display: block; }
.participate-meta span { margin-bottom: .45rem; color: var(--mint); font-size: .68rem; text-transform: uppercase; letter-spacing: .11em; }
.participate-meta strong { font-size: .95rem; }

footer { display: grid; grid-template-columns: 1fr 2fr 1fr; gap: 2rem; align-items: center; padding: 2rem max(2rem, calc((100vw - var(--max)) / 2)); background: var(--ink); color: rgba(244,241,232,.5); font-size: .72rem; }
.footer-brand { color: var(--paper); }
.footer-brand .brand-mark { width: 28px; height: 28px; }
footer p { margin: 0; }
footer p:last-child { text-align: right; }

.reveal { opacity: 0; transform: translateY(24px); transition: opacity .65s ease, transform .65s ease; }
.reveal.visible { opacity: 1; transform: none; }
@keyframes spin { to { transform: rotate(360deg); } }

@media (max-width: 900px) {
  .site-header { padding-inline: 1.25rem; }
  .menu-toggle { display: block; position: relative; z-index: 2; }
  .site-nav { position: fixed; inset: 0; display: flex; flex-direction: column; align-items: flex-start; justify-content: center; padding: 5rem 2rem; gap: 1.5rem; background: var(--ink); transform: translateX(100%); transition: transform .25s ease; }
  .site-nav.open { transform: none; }
  .site-nav a { font-size: 1.5rem; }
  .menu-toggle[aria-expanded="true"] span:nth-child(2) { transform: translateY(4.5px) rotate(45deg); }
  .menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-4.5px) rotate(-45deg); }
  .hero { grid-template-columns: 1fr; padding-inline: 1.25rem; padding-top: 8rem; padding-bottom: 5rem; }
  .hero-system { width: min(86vw, 500px); justify-self: center; }
  .hero-footnote { display: none; }
  .section-pad { padding-inline: 1.25rem; }
  .statement-grid, .failure-grid { grid-template-columns: 1fr; gap: 2.5rem; }
  .section-heading { grid-template-columns: 1fr; gap: 1rem; }
  .section-heading .section-index { margin-bottom: 1.5rem; }
  .model-layout { grid-template-columns: 1fr; }
  .model-tabs { grid-template-columns: repeat(2, 1fr); }
  .model-tab { border-right: 1px solid var(--line-dark); }
  .model-panel { min-height: 480px; }
  .assurance-loop { grid-template-columns: repeat(2, 1fr); }
  .assurance-quote { grid-template-columns: 1fr; }
  .assurance-quote span { text-align: left; }
  .participate { grid-template-columns: 1fr; }
  .participate-copy, .participate-meta { padding-inline: 1.25rem; }
  .participate-meta { border-left: 0; border-top: 1px solid var(--line-light); }
  footer { grid-template-columns: 1fr; padding-inline: 1.25rem; }
  footer p:last-child { text-align: left; }
}

@media (max-width: 560px) {
  h1 { font-size: clamp(3.2rem, 16vw, 5rem); }
  .hero-actions { align-items: flex-start; flex-direction: column; }
  .hero-system { width: 100%; }
  .system-node { font-size: .55rem; }
  .system-node-core { inset: 32%; }
  .system-node-core strong { font-size: .9rem; }
  .model-tabs, .assurance-loop, .research-grid { grid-template-columns: 1fr; }
  .model-tab { min-height: 88px; border-right: 0; }
  .loop-step { min-height: 240px; }
  .loop-step strong { margin-top: 4rem; }
  .assurance-quote { padding-top: 3.5rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; }
  .reveal { opacity: 1; transform: none; }
}