/* Self-hosted fonts (privacy + perf) */
@font-face {
  font-family: 'Fraunces';
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
  src: url('/assets/fonts/fraunces.woff2') format('woff2');
}
@font-face {
  font-family: 'Inter';
  font-style: normal;
  font-weight: 100 900;
  font-display: swap;
  src: url('/assets/fonts/inter.woff2') format('woff2');
}
@font-face {
  font-family: 'JetBrains Mono';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('/assets/fonts/jetbrainsmono.woff2') format('woff2');
}

/* SVG mark colour tokens (CQ-08) */
.mark-loop { stroke: var(--ink); fill: none; }
.mark-arrow { stroke: var(--accent); fill: none; }

:root {
  --paper: #FBF7F0;
  --paper-edge: #F1EBE0;
  --ink: #14181F;
  --ink-soft: #3A4150;
  --ink-mute: #595F69;
  --surface: #FFFFFF;
  --eyebrow-on-ink: #B9CFCB;
  --rule: #E2D9C6;
  --accent: #0F4F4A;
  --accent-soft: #DDEDEA;
  --accent-ink: #083936;
  --warn: #B6442A;

  --serif: 'Fraunces', Georgia, 'Iowan Old Style', serif;
  --sans:  'Inter', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', sans-serif;
  --mono:  'JetBrains Mono', ui-monospace, Menlo, monospace;

  --max: 1080px;
  --narrow: 720px;
  --pad-x: clamp(20px, 4vw, 40px);
}

* { box-sizing: border-box; }

/* Skip link */
.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 100;
  background: var(--ink);
  color: var(--paper);
  padding: 12px 18px;
  font-family: var(--sans);
  font-weight: 500;
  font-size: 14px;
  border-radius: 2px;
  border: 0;
  text-decoration: none;
  transition: top .15s ease;
}
.skip-link:focus {
  top: 12px;
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  color: var(--paper);
}
html { -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: no-preference) {
  html { scroll-behavior: smooth; }
}
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 18px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; border-bottom: 1px solid currentColor; transition: color .15s ease; }
a:hover { color: var(--accent-ink); }
a:focus-visible,
button:focus-visible,
.btn-primary:focus-visible,
.btn-secondary:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 2px;
}
.brand:focus-visible { outline-offset: 4px; }

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}
.wrap.narrow { max-width: var(--narrow); }

/* Header */
.site-header {
  border-bottom: 1px solid var(--rule);
  background: var(--paper);
  position: sticky; top: 0; z-index: 10;
  backdrop-filter: saturate(140%) blur(6px);
}
.nav {
  display: flex; align-items: center; justify-content: space-between;
  height: 68px;
}
.brand {
  display: inline-flex; align-items: center; gap: 12px;
  font-family: var(--serif); font-weight: 500; font-size: 18px;
  color: var(--ink); border: 0; letter-spacing: .005em;
}
.brand-mark-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
  display: inline-block;
}
.nav-links { display: flex; gap: 28px; }
.nav-links a {
  color: var(--ink-soft); border: 0; font-size: 15px; font-weight: 500;
}
.nav-links a:hover { color: var(--accent-ink); }

@media (max-width: 640px) {
  .nav-links { display: none; }
}

/* Hero */
.hero { padding: clamp(56px, 12vw, 140px) 0 clamp(40px, 8vw, 80px); }
.eyebrow {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--accent);
  margin: 0 0 28px;
}
.hero-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(40px, 7vw, 84px);
  line-height: 1.02;
  letter-spacing: -.02em;
  margin: 0 0 24px;
  max-width: 18ch;
}
.hero-lede {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(22px, 3vw, 30px);
  line-height: 1.3;
  color: var(--ink-soft);
  margin: 0 0 36px;
  max-width: 28ch;
}
.hero-sub {
  font-size: 19px;
  line-height: 1.7;
  color: var(--ink-soft);
  max-width: 60ch;
  margin: 0;
}
.hero-sub strong { font-weight: 600; color: var(--ink); }

/* Hero CTAs */
.hero-cta {
  display: flex;
  align-items: center;
  gap: 18px;
  margin-top: 44px;
  flex-wrap: wrap;
}
.btn-primary {
  display: inline-block;
  padding: 14px 24px;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--sans);
  font-weight: 500;
  font-size: 16px;
  border: 0;
  border-radius: 2px;
  text-decoration: none;
  transition: background .15s ease;
}
.btn-primary:hover { background: var(--accent-ink); color: var(--paper); }
.btn-secondary {
  display: inline-flex;
  align-items: center;
  padding: 14px 4px;
  color: var(--ink-soft);
  font-family: var(--sans);
  font-weight: 500;
  font-size: 16px;
  border: 0;
  border-bottom: 1px solid var(--rule);
  text-decoration: none;
  transition: color .15s ease, border-color .15s ease;
}
.btn-secondary:hover { color: var(--accent-ink); border-bottom-color: var(--accent); }

/* SODA section */
.soda {
  background: var(--paper-edge);
}
.soda .lead { max-width: 56ch; }
.soda-diagram {
  margin: 48px 0 56px;
  padding: 0;
  text-align: center;
}
.soda-diagram img {
  width: 100%;
  max-width: 1100px;
  height: auto;
  display: block;
  margin: 0 auto;
}
@media (max-width: 760px) {
  .soda-diagram {
    margin: 32px -16px 36px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .soda-diagram img {
    min-width: 1000px;
    max-width: none;
  }
}
.soda-phases {
  list-style: none; padding: 0; margin: 0;
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 28px 32px;
}
.soda-phases li {
  background: var(--surface);
  border: 1px solid var(--rule);
  border-left: 3px solid var(--accent);
  border-radius: 2px;
  padding: 24px 26px;
}
.soda-phases h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 20px;
  margin: 0 0 10px;
  color: var(--ink);
  display: flex; align-items: baseline; gap: 12px;
}
.soda-phases .num {
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: .04em;
}
.soda-phases p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.55;
}
@media (max-width: 720px) {
  .soda-phases { grid-template-columns: 1fr; gap: 18px; }
}

/* Closing callout */
.closing-callout {
  background: var(--ink);
  color: var(--paper);
  padding: clamp(60px, 10vw, 96px) 0;
  border-top: 0;
  border-bottom: 0;
}
.closing-callout .callout-eyebrow {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--eyebrow-on-ink);
  margin: 0 0 22px;
}
.closing-callout .callout-quote {
  margin: 0;
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(26px, 3.6vw, 40px);
  line-height: 1.18;
  letter-spacing: -.012em;
  color: var(--paper);
  max-width: 30ch;
  border: 0;
  padding: 0;
}

/* Sections */
section { padding: clamp(56px, 10vw, 120px) 0; border-top: 1px solid var(--rule); }
section.hero { border-top: 0; padding-top: clamp(80px, 12vw, 140px); }
.section-eyebrow {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--accent);
  margin: 0 0 24px;
}
.section-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(28px, 4.4vw, 44px);
  line-height: 1.15;
  letter-spacing: -.012em;
  margin: 0 0 36px;
  color: var(--ink);
}
.lead {
  font-size: 20px;
  color: var(--ink-soft);
  max-width: 60ch;
  margin: 0 0 28px;
}

/* Arc */
.arc { background: var(--paper-edge); }
.arc-list {
  list-style: none; padding: 0; margin: 0;
  display: grid; gap: 14px;
}
.arc-list li {
  display: grid;
  grid-template-columns: minmax(160px, 240px) 1fr;
  gap: 24px;
  align-items: baseline;
  padding: 20px 0;
  border-bottom: 1px solid var(--rule);
  font-size: clamp(20px, 2.4vw, 26px);
  font-family: var(--serif);
}
.arc-list li:last-child { border-bottom: 0; }
@media (max-width: 640px) {
  .arc-list li {
    grid-template-columns: 1fr;
    gap: 4px;
    padding: 16px 0;
  }
  .arc-list .arc-rule { font-size: 0.92em; }
}
.arc-era {
  font-weight: 600;
  color: var(--ink);
  letter-spacing: -.005em;
}
.arc-rule {
  color: var(--ink-soft);
  font-style: italic;
}
.arc-now .arc-era { color: var(--accent-ink); }
.arc-now .arc-rule { color: var(--accent-ink); font-style: normal; font-weight: 500; }

/* Manifesto values */
.values {
  list-style: none; padding: 0; margin: 0 0 28px;
  display: grid; gap: 0;
  border-top: 1px solid var(--rule);
}
.values li {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 18px;
  align-items: baseline;
  padding: 18px 0;
  border-bottom: 1px solid var(--rule);
  font-family: var(--serif);
  font-size: clamp(18px, 2.2vw, 22px);
}
.values .left { color: var(--ink); font-weight: 500; }
.values .vs {
  font-family: var(--mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .2em;
  color: var(--ink-mute);
  padding-top: 6px;
}
.values .right { color: var(--ink-mute); font-style: italic; text-align: right; }
@media (max-width: 640px) {
  .values li {
    grid-template-columns: 1fr;
    gap: 4px;
    padding: 16px 0;
  }
  .values .right { text-align: left; }
  .values .vs { padding-top: 0; }
}
.footnote {
  font-size: 15px;
  color: var(--ink-mute);
  font-style: italic;
  margin: 24px 0 0;
}

/* Why-now: real moment callout */
.why-example {
  margin: 16px 0 40px;
  padding: 28px 30px;
  background: var(--paper-edge);
  border-left: 3px solid var(--accent);
  border-radius: 2px;
}
.why-example-eyebrow {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--accent);
  margin: 0 0 14px;
  font-weight: 500;
}
.why-example-quote {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(20px, 2.4vw, 24px);
  line-height: 1.32;
  color: var(--ink);
  margin: 0 0 14px;
  letter-spacing: -.005em;
}
.why-example p:last-child {
  font-family: var(--serif);
  font-size: 17px;
  line-height: 1.55;
  color: var(--ink-soft);
  margin: 0;
}

/* Why prose */
.prose p {
  font-family: var(--serif);
  font-size: clamp(19px, 2vw, 22px);
  line-height: 1.6;
  color: var(--ink);
  margin: 0 0 1.1em;
}
.prose p:last-child { margin-bottom: 0; }

/* Principles */
.principles-list {
  list-style: none; padding: 0; margin: 0;
  counter-reset: prin;
  display: grid; gap: 0;
  border-top: 1px solid var(--rule);
}
.principles-list li {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 18px;
  align-items: baseline;
  padding: 22px 0;
  border-bottom: 1px solid var(--rule);
  font-family: var(--serif);
  font-size: clamp(19px, 2.2vw, 22px);
  line-height: 1.45;
  color: var(--ink);
}
.principles-list .num,
.layers .num {
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: .04em;
  padding-top: 4px;
}

/* 8-Layer Model */
.layers {
  list-style: none; padding: 0; margin: 32px 0 0;
  display: grid; gap: 32px;
}
.layers li {
  padding: 28px;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 4px;
}
.layers h3 {
  font-family: var(--serif);
  font-weight: 600;
  font-size: clamp(20px, 2.4vw, 24px);
  line-height: 1.2;
  margin: 0 0 12px;
  color: var(--ink);
  display: flex; align-items: baseline; gap: 12px;
}
.layers h3 .num {
  display: inline-block; padding-top: 0;
}
.layers p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 17px;
  line-height: 1.65;
}

/* About */
.about .prose,
.about p { color: var(--ink); }
.about .section-title a {
  color: inherit;
  border: 0;
  text-decoration: none;
}
.about .section-title a:hover { color: var(--accent-ink); }
.about-byline {
  font-family: var(--serif);
  font-size: 18px;
  color: var(--ink-soft);
  margin: 0 0 32px;
  font-style: italic;
}
.about .lineage {
  font-size: 17px;
  color: var(--ink-soft);
  border-left: 3px solid var(--rule);
  padding-left: 20px;
  margin-top: 32px;
}
.about .lineage-label {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 11px;
  letter-spacing: .18em;
  color: var(--accent);
  margin-right: 8px;
  font-weight: 500;
}
.cta-quiet {
  font-family: var(--serif);
  font-size: 17px;
  color: var(--ink-soft);
  margin: 32px 0 0;
  font-style: italic;
}
.cta-quiet a { color: var(--accent-ink); }

/* Lede callout (the "shift in one line") */
.lede-callout {
  background: var(--paper-edge);
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
  padding: clamp(40px, 8vw, 72px) 0;
}
.lede-callout .callout-eyebrow {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--accent);
  margin: 0 0 18px;
}
.lede-callout .callout-quote {
  margin: 0;
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(22px, 3.4vw, 36px);
  line-height: 1.22;
  letter-spacing: -.012em;
  color: var(--ink);
  max-width: 28ch;
  border: 0;
  padding: 0;
}

/* Arc diagram — historical arc (4 models, external SVG) */
.arc-diagram {
  margin: 40px 0 56px;
  padding: 0;
  text-align: center;
}
.arc-diagram img,
.arc-diagram svg {
  width: 100%;
  max-width: 1180px;
  height: auto;
  display: block;
  margin: 0 auto;
}

/* Lineage diagram (Lean vs Adaptive comparison, separate section) */
.lineage-diagram {
  background: var(--paper-edge);
}
.comparison-diagram {
  margin: 16px 0 0;
  padding: 0;
  text-align: center;
}
.comparison-diagram img {
  width: 100%;
  max-width: 1180px;
  height: auto;
  display: block;
  margin: 0 auto;
}

.visually-hidden {
  position: absolute !important;
  width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}
@media (max-width: 760px) {
  .arc-diagram {
    margin: 28px -16px 36px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .arc-diagram img,
  .arc-diagram svg { min-width: 1000px; max-width: none; }
  .comparison-diagram {
    margin: 16px -16px 0;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
  }
  .comparison-diagram img {
    min-width: 1000px;
    max-width: none;
  }
}

/* Next */
.next { background: var(--paper-edge); }
.next-list {
  list-style: none; padding: 0; margin: 0;
  display: grid; gap: 14px;
  font-family: var(--serif);
  font-size: clamp(17px, 1.9vw, 20px);
  color: var(--ink-soft);
}
.next-list strong { color: var(--ink); font-weight: 600; }

/* Licence */
.cite-callout {
  margin: 32px 0 28px;
  padding: 0;
  border: 0;
  background: transparent;
}
.cite-callout figcaption {
  font-family: var(--mono);
  text-transform: uppercase;
  font-size: 12px;
  letter-spacing: .18em;
  color: var(--accent);
  margin: 0 0 12px;
}
.cite-callout {
  position: relative;
}
.cite-copy {
  position: absolute;
  top: 38px;
  right: 14px;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: .12em;
  text-transform: uppercase;
  background: var(--paper);
  color: var(--accent);
  border: 1px solid var(--rule);
  border-radius: 2px;
  padding: 7px 12px;
  cursor: pointer;
  transition: background .15s ease, color .15s ease, border-color .15s ease;
  font-weight: 500;
}
.cite-copy:hover {
  background: var(--accent);
  color: var(--paper);
  border-color: var(--accent);
}
.cite-copy.is-copied {
  background: var(--accent-ink);
  color: var(--paper);
  border-color: var(--accent-ink);
}
@media (max-width: 540px) {
  .cite-copy {
    position: static;
    margin-top: 12px;
    display: inline-block;
  }
}

.cite-callout .cite,
.licence .cite {
  font-family: var(--mono);
  font-size: 15px;
  line-height: 1.6;
  background: var(--surface);
  color: var(--ink);
  padding: 22px 26px;
  border-left: 4px solid var(--accent);
  border-radius: 2px;
  white-space: pre-wrap;
  margin: 0;
  overflow-x: auto;
  box-shadow: 0 1px 0 var(--rule);
}
.licence .licence-note {
  font-size: 14px;
  color: var(--ink-mute);
  font-style: italic;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 48px 0;
  background: var(--paper);
}
.foot-line {
  font-family: var(--serif);
  font-style: italic;
  color: var(--ink-soft);
  margin: 0 0 8px;
  font-size: 15px;
}
.foot-cred {
  font-size: 13px;
  color: var(--ink-mute);
  margin: 0;
  font-family: var(--mono);
}
.foot-cred a { color: var(--ink-soft); border: 0; }
.foot-year { margin-left: 8px; }

/* Print stylesheet */
@media print {
  .site-header, .nav-links, .hero-cta, .skip-link, .closing-callout, .next, .cite-copy { display: none !important; }
  body { background: var(--surface); color: #000; font-size: 11pt; line-height: 1.5; }
  main { max-width: 100%; }
  .wrap { max-width: 100%; padding: 0 12pt; }
  section { padding: 18pt 0; border-top: 0.5pt solid #ccc; page-break-inside: avoid; }
  h1, h2, h3 { color: #000; page-break-after: avoid; }
  .hero-title { font-size: 28pt; }
  .section-title { font-size: 18pt; }
  .arc-diagram, .comparison-diagram, .soda-diagram, .why-example { page-break-inside: avoid; }
  a { color: #000; border-bottom: 0.5pt solid #999; }
  a[href^="http"]:after { content: " (" attr(href) ")"; font-size: 9pt; color: #666; }
  .values li, .principles-list li, .layers li { page-break-inside: avoid; }
}