:root {
  --ink: #101522;
  --blue: #3154d7;
  --blue-dark: #203ca9;
  --eyebrow-on-dark: #d9e0ff;
  --muted: #626c7d;
  --line: #e1e5ec;
  --soft: #f6f7f3;
  --blue-soft: #eef2ff;
  --white: #fff;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font: 16px/1.7 Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; }
a:focus-visible, button:focus-visible { outline: 3px solid #8ea2ff; outline-offset: 3px; }
.wrap { width: min(1120px, calc(100% - 40px)); margin: 0 auto; }
.skip { position: absolute; left: -9999px; top: 8px; z-index: 100; background: var(--ink); color: #fff; padding: 10px 14px; }
.skip:focus { left: 8px; }

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255,255,255,.94);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav { min-height: 70px; display: flex; align-items: center; gap: 24px; }
.brand { display: inline-flex; align-items: center; gap: 9px; text-decoration: none; font-weight: 900; letter-spacing: -.02em; }
.logo { width: 34px; height: 34px; display: grid; place-items: center; border-radius: 10px; color: #fff; background: var(--ink); }
.nav-links { margin-left: auto; display: flex; align-items: center; gap: 24px; font-size: 14px; }
.nav-links a { text-decoration: none; color: #525d70; font-weight: 700; }
.nav-links a[aria-current="page"] { color: var(--blue); }
.button { display: inline-flex; align-items: center; justify-content: center; border-radius: 999px; padding: 12px 18px; background: var(--ink); color: #fff !important; text-decoration: none; font-weight: 850; line-height: 1.2; }
.button.blue { background: var(--blue); }
.button.light { background: #fff; color: var(--ink) !important; }

.hero { padding: 92px 0 76px; background: radial-gradient(circle at 86% 12%, #e7ecff 0, transparent 34%), var(--white); }
.hero-grid { display: grid; grid-template-columns: 1.1fr .9fr; gap: 64px; align-items: end; }
.eyebrow { color: var(--blue); font-size: 12px; font-weight: 900; letter-spacing: .11em; text-transform: uppercase; }
h1 { margin: 14px 0 22px; max-width: 850px; font-size: clamp(44px, 6.2vw, 76px); line-height: .98; letter-spacing: -.055em; }
.hero p { max-width: 680px; margin: 0; color: #515c6f; font-size: 19px; }
.hero-note { border: 1px solid #d8def0; border-radius: 22px; background: rgba(255,255,255,.84); padding: 24px; box-shadow: 0 18px 55px rgba(16,21,34,.08); }
.hero-note strong { display: block; margin-bottom: 7px; font-size: 18px; }
.hero-note p { font-size: 14px; }

.breadcrumb { padding: 24px 0 0; color: var(--muted); font-size: 13px; }
.breadcrumb a { color: var(--blue); text-decoration: none; }
.article-hero { padding: 48px 0 58px; border-bottom: 1px solid var(--line); background: radial-gradient(circle at 86% 5%, #e8edff 0, transparent 32%); }
.article-hero h1 { font-size: clamp(42px, 6vw, 68px); max-width: 980px; }
.dek { max-width: 780px; color: #4e596c; font-size: 20px; }
.meta { display: flex; flex-wrap: wrap; gap: 9px 18px; margin-top: 25px; color: var(--muted); font-size: 13px; }
.meta span + span::before { content: "•"; margin-right: 18px; color: #a2a9b5; }

.article-layout { display: grid; grid-template-columns: minmax(0, 720px) 250px; gap: 72px; align-items: start; padding: 58px 0 90px; }
.article { min-width: 0; }
.article > p:first-child { font-size: 20px; line-height: 1.65; color: #3e495b; }
.article h2 { margin: 58px 0 16px; font-size: clamp(29px, 4vw, 40px); line-height: 1.12; letter-spacing: -.035em; }
.article h3 { margin: 34px 0 10px; font-size: 23px; line-height: 1.25; letter-spacing: -.02em; }
.article p { margin: 0 0 20px; }
.article ul, .article ol { margin: 0 0 24px; padding-left: 23px; }
.article li { margin: 8px 0; padding-left: 4px; }
.article a { color: var(--blue-dark); text-decoration-thickness: 1px; text-underline-offset: 3px; }
.article strong { font-weight: 850; }
.toc { position: sticky; top: 94px; border-left: 2px solid var(--line); padding-left: 20px; font-size: 13px; }
.toc strong { display: block; margin-bottom: 10px; }
.toc a { display: block; padding: 5px 0; color: var(--muted); text-decoration: none; }
.toc a:hover { color: var(--blue); }
.callout { margin: 30px 0; padding: 23px 25px; border: 1px solid #d5dcfa; border-radius: 18px; background: var(--blue-soft); }
.callout strong { display: block; margin-bottom: 7px; }
.callout p:last-child { margin-bottom: 0; }
.example { margin: 28px 0; overflow: hidden; border: 1px solid var(--line); border-radius: 18px; }
.example-row { display: grid; grid-template-columns: 145px 1fr; border-top: 1px solid var(--line); }
.example-row:first-child { border-top: 0; }
.example-label { padding: 18px; background: var(--soft); color: var(--muted); font-size: 12px; font-weight: 900; letter-spacing: .06em; text-transform: uppercase; }
.example-copy { padding: 18px 20px; }
.checklist { margin: 28px 0; padding: 25px 27px; border-radius: 18px; background: var(--ink); color: #fff; }
.checklist h3 { margin-top: 0; }
.checklist ul { list-style: none; padding: 0; margin-bottom: 0; }
.checklist li { position: relative; padding-left: 27px; color: #d9deea; }
.checklist li::before { content: "✓"; position: absolute; left: 0; color: #9bb0ff; font-weight: 900; }

.article-cta { margin-top: 62px; padding: 34px; border-radius: 24px; background: var(--blue); color: #fff; }
.hub-cta .eyebrow, .article-cta .eyebrow { color: var(--eyebrow-on-dark); }
.article-cta h2 { margin: 9px 0 12px; font-size: 34px; }
.article-cta p { max-width: 600px; color: #edf0ff; }
.related { padding: 78px 0; background: var(--soft); border-top: 1px solid var(--line); }
.related h2 { margin: 8px 0 28px; font-size: 38px; letter-spacing: -.04em; }
.related-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; }
.related-card { border: 1px solid var(--line); border-radius: 19px; padding: 23px; background: #fff; text-decoration: none; }
.related-card small { color: var(--blue); font-weight: 850; }
.related-card strong { display: block; margin-top: 6px; font-size: 19px; line-height: 1.3; }

.hub-intro { padding: 78px 0 30px; }
.hub-intro h1 { max-width: 780px; }
.hub-intro p { max-width: 690px; color: var(--muted); font-size: 19px; }
.guide-list { padding: 35px 0 96px; }
.guide-card { display: grid; grid-template-columns: 86px 1fr auto; gap: 28px; align-items: center; padding: 30px 0; border-top: 1px solid var(--line); text-decoration: none; }
.guide-card:last-child { border-bottom: 1px solid var(--line); }
.guide-number { color: var(--blue); font-size: 13px; font-weight: 900; letter-spacing: .1em; }
.guide-card h2 { margin: 0 0 7px; font-size: clamp(24px, 3vw, 34px); line-height: 1.15; letter-spacing: -.035em; }
.guide-card p { margin: 0; max-width: 720px; color: var(--muted); }
.guide-arrow { width: 43px; height: 43px; display: grid; place-items: center; border-radius: 50%; background: var(--blue-soft); color: var(--blue); font-size: 21px; transition: transform .2s ease; }
.guide-card:hover .guide-arrow { transform: translateX(4px); }
.hub-cta { padding: 76px 0; color: #fff; background: var(--ink); }
.hub-cta-inner { display: flex; align-items: center; justify-content: space-between; gap: 36px; }
.hub-cta h2 { margin: 8px 0 10px; font-size: clamp(32px, 4vw, 48px); line-height: 1.05; letter-spacing: -.04em; }
.hub-cta p { max-width: 640px; margin: 0; color: #bdc5d4; }

.site-footer { padding: 35px 0; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
.footer-row { display: flex; justify-content: space-between; gap: 24px; }
.footer-row a { color: var(--ink); }

@media (max-width: 860px) {
  .hero-grid, .article-layout { grid-template-columns: 1fr; }
  .hero-grid { gap: 32px; }
  .toc { position: static; order: -1; border-left: 0; border-bottom: 1px solid var(--line); padding: 0 0 24px; }
  .article-layout { gap: 30px; }
  .related-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  .wrap { width: min(100% - 28px, 1120px); }
  .nav-links > a:not(.button) { display: none; }
  .hero, .hub-intro { padding-top: 60px; }
  .article-hero { padding-top: 35px; }
  h1, .article-hero h1 { font-size: 42px; }
  .guide-card { grid-template-columns: 52px 1fr; gap: 14px; }
  .guide-arrow { display: none; }
  .example-row { grid-template-columns: 1fr; }
  .example-label { padding-bottom: 7px; }
  .example-copy { padding-top: 7px; }
  .hub-cta-inner, .footer-row { align-items: flex-start; flex-direction: column; }
  .meta span + span::before { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}