:root {
  --ink: #0b1319;
  --ink-soft: #101e28;
  --panel: #142733;
  --paper: #eef4f2;
  --muted: #aab9ba;
  --line: rgba(238, 244, 242, 0.16);
  --line-dark: rgba(11, 19, 25, 0.14);
  --blue: #9fc1ff;
  --teal: #68decf;
  --orange: #ffb777;
  --white: #ffffff;
  --max: 1180px;
  --serif: Georgia, 'Times New Roman', serif;
  --sans: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration-thickness: 0.08em; text-underline-offset: 0.17em; }
a:hover { color: var(--teal); }
img { max-width: 100%; display: block; }
button, a { -webkit-tap-highlight-color: transparent; }

.site-shell { min-height: 100vh; overflow: hidden; }
.container { width: min(calc(100% - 48px), var(--max)); margin: 0 auto; }
.container-narrow { width: min(calc(100% - 48px), 820px); margin: 0 auto; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(11, 19, 25, 0.88);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(18px);
}
.nav {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.brand { display: inline-flex; align-items: center; gap: 12px; font-weight: 700; letter-spacing: -0.02em; text-decoration: none; }
.brand-mark {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border: 1px solid var(--teal);
  color: var(--teal);
  border-radius: 50%;
  font-size: 12px;
  letter-spacing: -0.06em;
}
.brand-name { font-size: 15px; }
.nav-links { display: flex; align-items: center; gap: 25px; font-size: 14px; color: var(--muted); }
.nav-links a { text-decoration: none; }
.nav-links a[aria-current='page'] { color: var(--paper); }
.nav-cta { color: var(--ink) !important; background: var(--teal); padding: 10px 15px; border-radius: 3px; font-weight: 700; }
.nav-cta:hover { color: var(--ink) !important; background: var(--white); }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 12px;
  line-height: 1.2;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--teal);
}
.eyebrow::before { content: ''; width: 22px; height: 1px; background: currentColor; }
h1, h2, h3, p { margin-top: 0; }
h1, h2, h3 { letter-spacing: -0.04em; line-height: 1.07; }
h1 { font-size: clamp(3.2rem, 7vw, 6.6rem); max-width: 900px; margin-bottom: 28px; font-weight: 600; }
h2 { font-size: clamp(2rem, 4vw, 3.6rem); margin-bottom: 22px; font-weight: 600; }
h3 { font-size: 1.3rem; margin-bottom: 10px; }
.display-serif { font-family: var(--serif); font-weight: 400; letter-spacing: -0.045em; }
.lead { font-size: clamp(1.15rem, 2vw, 1.45rem); line-height: 1.5; color: #d6e0dd; max-width: 690px; }
.muted { color: var(--muted); }
.small { font-size: 13px; color: var(--muted); }
.lede { max-width: 690px; color: var(--muted); font-size: 1.12rem; }

.button-row { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 11px 17px;
  border: 1px solid var(--teal);
  border-radius: 3px;
  text-decoration: none;
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0.01em;
}
.button-primary { color: var(--ink); background: var(--teal); }
.button-primary:hover { color: var(--ink); background: var(--white); border-color: var(--white); }
.button-secondary { color: var(--paper); border-color: var(--line); }
.button-secondary:hover { color: var(--paper); border-color: var(--teal); }

.hero { padding: 100px 0 90px; position: relative; }
.hero-grid { display: grid; grid-template-columns: minmax(0, 1.2fr) minmax(290px, 0.8fr); gap: 80px; align-items: end; }
.hero h1 { margin-top: 24px; }
.hero h1 em { color: var(--blue); font-family: var(--serif); font-weight: 400; }
.hero-aside { border-top: 1px solid var(--line); padding-top: 18px; margin-bottom: 11px; }
.hero-aside .label { text-transform: uppercase; letter-spacing: .16em; font-size: 11px; color: var(--muted); }
.hero-aside p { font-size: 1.35rem; line-height: 1.25; letter-spacing: -0.03em; margin: 15px 0 24px; }
.hero-aside a { color: var(--teal); font-size: 14px; font-weight: 700; }
.signal-line { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); padding: 14px 0; color: var(--muted); font-size: 12px; letter-spacing: .13em; text-transform: uppercase; white-space: nowrap; overflow: hidden; }
.signal-line span { color: var(--teal); margin: 0 11px; }

.section { padding: 106px 0; }
.section-tint { background: #101c24; }
.section-light { background: var(--paper); color: var(--ink); }
.section-head { display: flex; justify-content: space-between; gap: 32px; align-items: end; margin-bottom: 42px; }
.section-head h2 { max-width: 610px; margin-bottom: 0; }
.section-head p { max-width: 440px; color: var(--muted); margin-bottom: 0; }
.section-light .section-head p { color: #516166; }

.card-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.card { background: var(--ink); padding: 29px; min-height: 285px; display: flex; flex-direction: column; justify-content: space-between; }
.section-tint .card { background: var(--panel); }
.section-light .card-grid { background: var(--line-dark); border-color: var(--line-dark); }
.section-light .card { background: var(--paper); }
.card-index { font-size: 12px; color: var(--teal); letter-spacing: .13em; }
.card p { color: var(--muted); margin-bottom: 0; }
.section-light .card p { color: #516166; }
.card a { font-weight: 700; font-size: 14px; }

.split { display: grid; grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr); gap: 90px; align-items: start; }
.split-reverse { grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr); }
.section-label { position: sticky; top: 110px; }
.section-label p { max-width: 300px; color: var(--muted); }
.section-light .section-label p { color: #516166; }
.numbered-list { border-top: 1px solid var(--line); }
.section-light .numbered-list { border-color: var(--line-dark); }
.numbered-item { display: grid; grid-template-columns: 50px 1fr; gap: 20px; padding: 24px 0; border-bottom: 1px solid var(--line); }
.section-light .numbered-item { border-color: var(--line-dark); }
.numbered-item .num { color: var(--orange); font-size: 12px; font-weight: 800; padding-top: 3px; }
.numbered-item h3 { margin-bottom: 7px; }
.numbered-item p { color: var(--muted); margin-bottom: 0; }
.section-light .numbered-item p { color: #516166; }

.book-feature { display: grid; grid-template-columns: minmax(230px, .65fr) minmax(0, 1.35fr); gap: 72px; align-items: center; }
.book-frame { max-width: 350px; margin: 0 auto; padding: 12px; border: 1px solid var(--line); background: #13222a; transform: rotate(-2deg); box-shadow: 19px 22px 0 rgba(104, 222, 207, .12); }
.book-poster { position: relative; min-height: 425px; overflow: hidden; background: #dce9ed; }
.book-poster img { width: 100%; height: 100%; min-height: 425px; object-fit: cover; filter: saturate(.7) contrast(.88); }
.book-poster::after { content: ''; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(10,17,22,.72) 0%, rgba(10,17,22,.12) 42%, rgba(10,17,22,.76) 100%); }
.book-poster-copy { position: absolute; z-index: 1; inset: 28px 24px; display: flex; flex-direction: column; justify-content: space-between; color: white; }
.book-poster-copy .book-kicker { font-size: 11px; letter-spacing: .16em; font-weight: 800; }
.book-poster-copy strong { font-family: var(--serif); font-size: clamp(2rem, 4vw, 3.5rem); line-height: .95; font-weight: 400; letter-spacing: -.05em; }
.book-poster-copy span { font-size: 12px; letter-spacing: .08em; }
.book-copy h2 { max-width: 660px; }
.book-copy p { max-width: 670px; color: var(--muted); font-size: 1.08rem; }
.inline-link { color: var(--teal); font-weight: 800; }

.article-card { display: grid; grid-template-columns: 60px 1fr; gap: 22px; padding: 26px 0; border-top: 1px solid var(--line); }
.article-card:last-child { border-bottom: 1px solid var(--line); }
.article-card .index { color: var(--orange); font-size: 12px; font-weight: 800; padding-top: 5px; }
.article-card h3 { margin: 0 0 8px; font-size: clamp(1.45rem, 2.6vw, 2.1rem); }
.article-card p { color: var(--muted); margin: 0 0 11px; max-width: 750px; }
.article-meta { font-size: 12px; color: var(--muted); letter-spacing: .05em; }

.page-hero { padding: 94px 0 68px; border-bottom: 1px solid var(--line); }
.page-hero h1 { margin: 20px 0; max-width: 850px; }
.page-hero .lead { max-width: 750px; }
.article-shell { padding: 70px 0 115px; }
.article-header { padding-bottom: 52px; border-bottom: 1px solid var(--line); margin-bottom: 55px; }
.article-header h1 { font-size: clamp(2.8rem, 6vw, 5.8rem); max-width: 900px; margin-top: 18px; }
.article-byline { display: flex; flex-wrap: wrap; gap: 13px 28px; color: var(--muted); font-size: 13px; }
.article-body { font-size: 1.13rem; line-height: 1.8; }
.article-body h2 { font-size: clamp(1.85rem, 3vw, 2.7rem); margin: 68px 0 20px; }
.article-body h3 { margin-top: 42px; }
.article-body p { color: #d4dfdc; }
.article-body strong { color: var(--paper); }
.article-body blockquote { margin: 45px 0; padding: 22px 0 22px 28px; border-left: 2px solid var(--teal); color: var(--paper); font-family: var(--serif); font-size: clamp(1.45rem, 3vw, 2.25rem); line-height: 1.25; letter-spacing: -.03em; }
.article-body ul { color: #d4dfdc; padding-left: 25px; }
.article-body li { padding-left: 7px; margin-bottom: 12px; }
.article-body .diagram { margin: 45px 0; padding: 18px; border: 1px solid var(--line); background: #0f1b23; }
.article-body .diagram figcaption { font-size: 12px; color: var(--muted); margin-top: 12px; }
.article-body .callout { margin: 42px 0; padding: 26px 28px; border: 1px solid rgba(255,183,119,.52); background: rgba(255,183,119,.06); }
.article-body .callout p:last-child { margin-bottom: 0; }
.article-footer { margin-top: 75px; padding-top: 34px; border-top: 1px solid var(--line); }

.diagram-label { font-size: 12px; fill: #dce8e5; font-family: Inter, Arial, sans-serif; }
.diagram-sub { font-size: 10px; fill: #8fa6a6; font-family: Inter, Arial, sans-serif; }
.diagram-box { fill: #152d38; stroke: #4d777c; stroke-width: 1; }
.diagram-box-accent { fill: #183b42; stroke: #68decf; stroke-width: 1; }
.diagram-line { stroke: #68decf; stroke-width: 1.5; fill: none; marker-end: url(#arrow); }

.timeline { border-left: 1px solid var(--line); }
.timeline-item { position: relative; padding: 0 0 45px 35px; }
.timeline-item::before { content: ''; position: absolute; left: -5px; top: 8px; width: 9px; height: 9px; border-radius: 50%; background: var(--teal); box-shadow: 0 0 0 5px var(--ink); }
.timeline-item h3 { margin-bottom: 6px; }
.timeline-item p { color: var(--muted); max-width: 650px; margin-bottom: 0; }
.principle-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.principle { background: var(--ink); padding: 28px; }
.principle strong { display: block; margin-bottom: 8px; font-size: 1.1rem; }
.principle p { color: var(--muted); margin-bottom: 0; }

.detail-table { width: 100%; border-collapse: collapse; font-size: 14px; }
.detail-table th, .detail-table td { text-align: left; vertical-align: top; padding: 15px 0; border-bottom: 1px solid var(--line); }
.detail-table th { width: 34%; color: var(--muted); font-weight: 500; }
.detail-table td { color: var(--paper); }
.section-light .detail-table th, .section-light .detail-table td { border-color: var(--line-dark); }
.section-light .detail-table th { color: #516166; }

.roadmap { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; }
.roadmap-item { border-top: 2px solid var(--teal); padding-top: 15px; }
.roadmap-item strong { display: block; line-height: 1.1; margin-bottom: 9px; }
.roadmap-item p { color: var(--muted); font-size: 13px; margin: 0; line-height: 1.45; }

.footer { border-top: 1px solid var(--line); padding: 35px 0 45px; color: var(--muted); }
.footer-grid { display: flex; justify-content: space-between; gap: 24px; align-items: start; }
.footer p { margin: 0; font-size: 13px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 20px; font-size: 13px; }

.fine-print { color: var(--muted); font-size: 12px; }
.rule { height: 1px; background: var(--line); margin: 26px 0; }

@media (max-width: 840px) {
  .container, .container-narrow { width: min(calc(100% - 32px), var(--max)); }
  .nav { min-height: 68px; }
  .nav-links { gap: 13px; }
  .nav-links a:not(.nav-cta) { display: none; }
  .hero { padding: 72px 0 65px; }
  .hero-grid, .split, .split-reverse, .book-feature { grid-template-columns: 1fr; gap: 44px; }
  .hero-aside { max-width: 440px; }
  .section { padding: 74px 0; }
  .section-head { display: block; margin-bottom: 28px; }
  .section-head p { margin-top: 16px; }
  .card-grid, .principle-grid { grid-template-columns: 1fr; }
  .card { min-height: 230px; }
  .section-label { position: static; }
  .book-frame { max-width: 300px; }
  .roadmap { grid-template-columns: repeat(2, 1fr); gap: 28px 14px; }
  .page-hero { padding: 70px 0 54px; }
  .article-shell { padding: 48px 0 82px; }
  .article-body { font-size: 1.05rem; }
}

@media (max-width: 520px) {
  h1 { font-size: clamp(2.7rem, 14vw, 4rem); }
  .hero h1 { margin-bottom: 20px; }
  .button-row { margin-top: 25px; }
  .button { width: 100%; }
  .article-card { grid-template-columns: 34px 1fr; gap: 10px; }
  .article-body blockquote { padding-left: 18px; }
  .roadmap { grid-template-columns: 1fr; }
  .footer-grid { display: block; }
  .footer-links { margin-top: 20px; }
}