:root {
  --ink: #17191d;
  --muted: #686b73;
  --paper: #f5f5f1;
  --white: #ffffff;
  --line: rgba(23, 25, 29, 0.12);
  --blue: #1769ff;
  --violet: #7e5cff;
  --coral: #ff6b4a;
  --mint: #bff5da;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }

.site-note {
  background: var(--ink);
  color: #fff;
  padding: 9px 24px;
  text-align: center;
  font-size: 12px;
  letter-spacing: 0.02em;
}
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 72px;
  padding: 0 clamp(24px, 5vw, 72px);
  border-bottom: 1px solid var(--line);
  background: rgba(245, 245, 241, 0.88);
  backdrop-filter: blur(18px);
}
.brand { display: flex; align-items: center; gap: 11px; font-weight: 720; letter-spacing: -0.02em; }
.brand-mark {
  display: grid;
  place-items: center;
  width: 36px;
  height: 36px;
  border-radius: 11px;
  background: var(--ink);
  color: #fff;
  font-size: 10px;
  letter-spacing: 0.08em;
}
nav { display: flex; gap: 28px; color: #4e5159; font-size: 14px; }
nav a:hover, nav a:focus-visible { color: var(--blue); }

.hero {
  display: grid;
  grid-template-columns: 1.03fr 0.97fr;
  min-height: 680px;
  overflow: hidden;
}
.hero-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 88px clamp(24px, 6.3vw, 96px);
}
.eyebrow {
  margin: 0 0 20px;
  color: var(--blue);
  font-size: 12px;
  font-weight: 760;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}
h1, h2, h3, p { margin-top: 0; }
h1 {
  max-width: 760px;
  margin-bottom: 26px;
  font-size: clamp(58px, 7.4vw, 112px);
  line-height: 0.91;
  letter-spacing: -0.067em;
  font-weight: 770;
}
.hero-lede { max-width: 650px; color: var(--muted); font-size: clamp(18px, 1.6vw, 23px); line-height: 1.48; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 16px; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 50px;
  padding: 0 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 720;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--blue); color: #fff; box-shadow: 0 12px 32px rgba(23, 105, 255, 0.25); }
.button-primary:hover { background: #0655e8; }
.button-secondary { border: 1px solid var(--line); background: rgba(255, 255, 255, 0.7); }
.source-note { max-width: 610px; margin: 24px 0 0; color: #7a7c83; font-size: 12px; line-height: 1.55; }

.hero-visual {
  position: relative;
  display: grid;
  place-items: center;
  min-height: 680px;
  background:
    radial-gradient(circle at 72% 18%, rgba(191, 245, 218, 0.92), transparent 30%),
    radial-gradient(circle at 18% 82%, rgba(126, 92, 255, 0.48), transparent 36%),
    linear-gradient(145deg, #e6e0ff 0%, #f3c3ae 52%, #fff4d7 100%);
}
.visual-orbit { position: absolute; border: 1px solid rgba(23, 25, 29, 0.16); border-radius: 50%; }
.orbit-one { width: 520px; height: 520px; }
.orbit-two { width: 710px; height: 710px; }
.device-card {
  position: relative;
  width: min(310px, 58vw);
  aspect-ratio: 0.53;
  padding: 28px 26px;
  border: 9px solid #181a1e;
  border-radius: 58px;
  background: rgba(250, 250, 247, 0.94);
  box-shadow: 0 48px 90px rgba(35, 27, 55, 0.28);
  transform: rotate(5deg);
}
.device-island { width: 88px; height: 23px; margin: 0 auto 68px; border-radius: 99px; background: #181a1e; }
.device-content { display: flex; flex-direction: column; gap: 8px; }
.device-content strong { font-size: 28px; letter-spacing: -0.04em; }
.device-content span:last-child { color: var(--muted); }
.device-kicker { color: var(--blue); font-size: 11px; font-weight: 760; letter-spacing: 0.1em; text-transform: uppercase; }
.device-path { position: absolute; left: 26px; right: 26px; bottom: 38px; display: flex; align-items: center; gap: 9px; color: #575a62; font-size: 11px; }
.device-path i { flex: 1; height: 1px; background: var(--line); }

.metrics { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: #fff; }
.metrics div { min-height: 126px; padding: 28px clamp(20px, 3vw, 48px); border-right: 1px solid var(--line); }
.metrics div:last-child { border-right: 0; }
.metrics strong { display: block; margin-bottom: 8px; font-size: 28px; letter-spacing: -0.04em; }
.metrics span { color: var(--muted); font-size: 13px; }

.section { padding: 120px clamp(24px, 6.3vw, 96px); }
.section-heading { display: grid; grid-template-columns: 1fr 0.72fr; gap: 80px; align-items: end; margin-bottom: 50px; }
h2 { margin-bottom: 18px; font-size: clamp(40px, 5.4vw, 76px); line-height: 0.98; letter-spacing: -0.055em; }
.section-heading p:last-child { margin: 0; color: var(--muted); font-size: 17px; line-height: 1.62; }
.guide-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.guide-card { min-height: 370px; padding: 28px; border: 1px solid var(--line); border-radius: 28px; background: #fff; box-shadow: 0 16px 50px rgba(24, 26, 30, 0.05); }
.guide-number { display: grid; place-items: center; width: 70px; height: 70px; margin-bottom: 60px; border-radius: 22px; font-weight: 780; }
.tone-1 { background: #dce8ff; color: #0d58e8; }.tone-2 { background: #def7e9; color: #08743d; }.tone-3 { background: #ffdfd6; color: #b93617; }
.guide-card > p { margin-bottom: 7px; color: var(--blue); font-size: 12px; font-weight: 750; text-transform: uppercase; letter-spacing: 0.09em; }
.guide-card h3 { margin-bottom: 12px; font-size: 26px; letter-spacing: -0.035em; }
.guide-card > span { display: block; min-height: 74px; color: var(--muted); font-size: 14px; line-height: 1.55; }
.guide-card a { color: var(--blue); font-size: 14px; font-weight: 720; }

.law-section { display: grid; grid-template-columns: 1.55fr 0.75fr; gap: 18px; padding: 0 clamp(24px, 6.3vw, 96px) 120px; }
.law-card, .law-aside { border-radius: 32px; }
.law-card { padding: clamp(36px, 6vw, 84px); background: #17191d; color: #fff; }
.law-card .eyebrow { color: #8cb5ff; }
.law-card > p:not(.eyebrow) { max-width: 820px; color: #c3c5ca; font-size: 17px; line-height: 1.68; }
.law-facts { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin: 36px 0; }
.law-facts div { padding: 24px; border: 1px solid rgba(255,255,255,0.14); border-radius: 20px; background: rgba(255,255,255,0.06); }
.law-facts strong { display: block; margin-bottom: 8px; font-size: 28px; }.law-facts span { color: #b7bac1; font-size: 13px; line-height: 1.45; }
.text-link { color: #8cb5ff; font-weight: 720; font-size: 14px; }
.law-aside { padding: 40px; background: var(--mint); }
.aside-label { display: block; margin-bottom: 30px; font-size: 12px; font-weight: 780; text-transform: uppercase; letter-spacing: 0.1em; }
.law-aside ul { margin: 0; padding-left: 20px; }.law-aside li { margin-bottom: 22px; line-height: 1.52; }

.parts-section { margin: 0 clamp(24px, 6.3vw, 96px) 120px; padding: clamp(44px, 7vw, 96px); border-radius: 34px; background: linear-gradient(135deg, var(--blue), #5132cd); color: #fff; }
.parts-section .eyebrow { color: #c9dcff; }.parts-section h2 { max-width: 900px; }.parts-section > p:not(.eyebrow) { max-width: 800px; color: #dce7ff; font-size: 18px; line-height: 1.65; }
.button-light { margin-top: 14px; background: #fff; color: var(--blue); }

footer { display: grid; grid-template-columns: 1fr 1fr; gap: 36px; padding: 60px clamp(24px, 6.3vw, 96px); border-top: 1px solid var(--line); background: #fff; }
footer strong { font-size: 20px; } footer p { margin: 8px 0 0; color: var(--muted); font-size: 13px; line-height: 1.55; }
.footer-links { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 18px; font-size: 13px; }
.trademark-note { grid-column: 1 / -1; max-width: 1000px; padding-top: 28px; border-top: 1px solid var(--line); }

@media (max-width: 900px) {
  nav { display: none; }
  .hero { grid-template-columns: 1fr; }
  .hero-visual { min-height: 560px; }
  .metrics { grid-template-columns: 1fr 1fr; }
  .metrics div:nth-child(2) { border-right: 0; }.metrics div:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .section-heading, .law-section { grid-template-columns: 1fr; gap: 24px; }
  .guide-grid { grid-template-columns: 1fr; }
  .guide-card { min-height: 330px; }
  footer { grid-template-columns: 1fr; }.footer-links { justify-content: flex-start; }.trademark-note { grid-column: 1; }
}

@media (max-width: 560px) {
  .site-note { padding-inline: 14px; }
  .site-header { min-height: 64px; }
  .brand { font-size: 14px; }
  .hero-copy { padding-top: 64px; padding-bottom: 64px; }
  h1 { font-size: 57px; }
  .hero-visual { min-height: 500px; }
  .metrics { grid-template-columns: 1fr; }
  .metrics div { border-right: 0; border-bottom: 1px solid var(--line); }
  .section { padding-top: 88px; padding-bottom: 88px; }
  .law-section { padding-bottom: 88px; }
  .law-facts { grid-template-columns: 1fr; }
  .parts-section { margin-bottom: 88px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}

/* Static library and article pages */
.skip-link { position: fixed; left: 16px; top: -80px; z-index: 100; padding: 12px 16px; border-radius: 10px; background: #fff; color: var(--ink); box-shadow: 0 10px 28px rgba(0,0,0,.16); }
.skip-link:focus { top: 16px; }
.menu-button { display: none; border: 1px solid var(--line); border-radius: 999px; background: #fff; padding: 9px 14px; color: var(--ink); font: inherit; }
.page-shell, .article-shell { width: min(100%, 1540px); margin: 0 auto; padding: 0 clamp(24px, 6.3vw, 96px) 120px; }
.article-shell { width: min(100%, 1280px); }
.page-hero, .article-hero { padding: 108px 0 72px; }
.page-hero { max-width: 1050px; }
.page-hero h1, .article-hero h1 { margin-bottom: 28px; font-size: clamp(52px, 7.2vw, 104px); line-height: .94; letter-spacing: -.065em; }
.page-hero > p:last-child, .article-deck { max-width: 850px; color: var(--muted); font-size: clamp(18px, 2vw, 25px); line-height: 1.55; }
.breadcrumbs { display: flex; flex-wrap: wrap; gap: 9px; padding-top: 30px; color: var(--muted); font-size: 13px; }
.breadcrumbs a { color: var(--blue); }
.article-meta { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; max-width: 840px; margin-top: 42px; overflow: hidden; border: 1px solid var(--line); border-radius: 22px; background: var(--line); }
.article-meta div { min-height: 105px; padding: 24px; background: #fff; }
.article-meta strong, .article-meta span { display: block; }
.article-meta strong { margin-bottom: 8px; font-size: 17px; }
.article-meta span { color: var(--muted); font-size: 12px; }
.quick-take { display: grid; grid-template-columns: 150px 1fr; gap: 28px; margin: 0 0 72px; padding: 30px; border: 1px solid rgba(23,105,255,.2); border-radius: 24px; background: #edf3ff; }
.quick-take strong { color: var(--blue); font-size: 12px; letter-spacing: .09em; text-transform: uppercase; }
.quick-take p { margin: 0; line-height: 1.65; }
.content-section, .source-ledger { max-width: 930px; margin: 0 0 86px; }
.content-section h2, .source-ledger h2 { font-size: clamp(34px, 4.6vw, 58px); line-height: 1.02; }
.content-section > p, .source-ledger > p { color: #4f525a; font-size: 17px; line-height: 1.76; }
.content-section [data-p4c-citation] { color: var(--blue); font-weight: 720; text-decoration: underline; text-underline-offset: 3px; }
.check-list { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; padding: 0; list-style: none; }
.check-list li { position: relative; min-height: 110px; padding: 24px 24px 24px 56px; border: 1px solid var(--line); border-radius: 20px; background: #fff; line-height: 1.55; }
.check-list li::before { content: '\\2713'; position: absolute; left: 23px; top: 23px; display: grid; place-items: center; width: 22px; height: 22px; border-radius: 50%; background: var(--mint); color: #08743d; font-size: 12px; font-weight: 800; }
.post-checks li::before { content: 'OK'; font-size: 8px; }
.step-list { display: grid; gap: 12px; padding: 0; list-style: none; counter-reset: steps; }
.step-list li { display: grid; grid-template-columns: 54px 1fr; gap: 20px; align-items: center; padding: 20px; border: 1px solid var(--line); border-radius: 18px; background: #fff; }
.step-list li > span { display: grid; place-items: center; width: 46px; height: 46px; border-radius: 14px; background: var(--ink); color: #fff; font-weight: 800; }
.step-list p { margin: 0; line-height: 1.55; }
.manual-callout, .parts-callout { display: grid; grid-template-columns: 1fr auto; gap: 44px; align-items: end; margin: 0 0 86px; padding: clamp(32px, 5vw, 64px); border-radius: 30px; }
.manual-callout { background: linear-gradient(135deg, #17191d, #30343d); color: #fff; }
.manual-callout h2, .parts-callout h2, .parts-callout h3 { margin-bottom: 16px; font-size: clamp(34px, 4.4vw, 58px); line-height: 1.02; }
.manual-callout p:not(.eyebrow) { max-width: 700px; color: #c3c5ca; line-height: 1.68; }
.callout-actions { display: flex; flex-direction: column; gap: 10px; align-items: stretch; }
.identity-card { display: grid; gap: 8px; margin-top: 26px; padding: 26px; border: 1px solid var(--line); border-radius: 22px; background: #fff; }
.identity-card span { color: var(--blue); font-size: 11px; font-weight: 780; letter-spacing: .09em; text-transform: uppercase; }
.identity-card strong { font-size: clamp(24px, 3vw, 36px); letter-spacing: -.035em; }
.identity-card small { color: var(--muted); font-size: 13px; }
.parts-callout { border: 1px solid rgba(23,105,255,.22); background: #edf3ff; }
.parts-callout > div > p:not(.eyebrow) { max-width: 780px; color: #4c5465; line-height: 1.68; }
.parts-callout a:not(.button) { color: var(--blue); text-decoration: underline; text-underline-offset: 3px; }
.risk-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin: 26px 0; }
.risk-grid > div { min-height: 190px; padding: 26px; border-radius: 21px; background: #fff; border: 1px solid var(--line); }
.risk-grid span { display: block; margin-bottom: 18px; color: var(--coral); font-size: 11px; font-weight: 780; text-transform: uppercase; letter-spacing: .09em; }
.risk-grid p { color: #53565e; line-height: 1.6; }
.source-stack { display: grid; gap: 10px; }
.source-pill { display: grid; grid-template-columns: minmax(180px, .75fr) 1fr; gap: 18px; padding: 19px 22px; border: 1px solid var(--line); border-radius: 16px; background: #fff; transition: border-color 160ms ease, transform 160ms ease; }
.source-pill:hover { transform: translateY(-1px); border-color: rgba(23,105,255,.45); }
.source-pill span { color: var(--blue); font-weight: 720; }
.source-pill small { color: var(--muted); line-height: 1.4; }
.related-section { margin-top: 120px; padding-top: 76px; border-top: 1px solid var(--line); }
.guide-grid.compact .guide-card { min-height: 320px; }
.center-action { display: flex; justify-content: center; margin-top: 36px; }
.sources-band { display: grid; grid-template-columns: .85fr 1.15fr; gap: 80px; padding: 110px clamp(24px, 6.3vw, 96px); border-top: 1px solid var(--line); }
.sources-band h2 { max-width: 650px; }
.filter-panel { position: sticky; top: 92px; z-index: 10; margin-bottom: 36px; padding: 26px; border: 1px solid var(--line); border-radius: 24px; background: rgba(255,255,255,.94); box-shadow: 0 16px 50px rgba(23,25,29,.08); backdrop-filter: blur(16px); }
.filter-panel label { display: block; margin-bottom: 10px; font-size: 12px; font-weight: 780; text-transform: uppercase; letter-spacing: .09em; }
.filter-panel input, .filter-panel select { width: 100%; min-height: 50px; border: 1px solid var(--line); border-radius: 14px; background: #fff; padding: 0 15px; color: var(--ink); font: inherit; }
.filter-panel input { margin-bottom: 12px; font-size: 17px; }
.filter-row { display: grid; grid-template-columns: 1fr 1fr auto; gap: 10px; }
.filter-row button { border: 0; border-radius: 14px; padding: 0 20px; background: var(--ink); color: #fff; font: inherit; font-weight: 700; }
#guide-count { margin: 15px 0 0; color: var(--muted); font-size: 13px; }
.library-grid, .model-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.library-card, .model-card { display: flex; flex-direction: column; min-height: 300px; padding: 28px; border: 1px solid var(--line); border-radius: 24px; background: #fff; }
.library-card > span, .model-card > span { margin-bottom: 36px; color: var(--blue); font-size: 11px; font-weight: 770; letter-spacing: .09em; text-transform: uppercase; }
.library-card h2, .model-card h2 { margin-bottom: 13px; font-size: 25px; line-height: 1.1; letter-spacing: -.035em; }
.library-card p, .model-card p { color: var(--muted); font-size: 14px; line-height: 1.58; }
.library-card a, .model-card a { margin-top: auto; padding-top: 22px; color: var(--blue); font-size: 14px; font-weight: 720; }
.library-card[hidden] { display: none; }
.empty-state { padding: 56px 20px; text-align: center; color: var(--muted); }
.parts-directory { display: grid; gap: 14px; margin-bottom: 100px; }
.parts-directory article { display: grid; grid-template-columns: 1fr auto; gap: 32px; align-items: center; padding: 28px 30px; border: 1px solid var(--line); border-radius: 22px; background: #fff; }
.parts-directory span { color: var(--blue); font-size: 11px; font-weight: 770; letter-spacing: .09em; }
.parts-directory h2 { margin: 5px 0 8px; font-size: 26px; }
.parts-directory p { max-width: 850px; margin: 0; color: var(--muted); line-height: 1.55; }
.source-directory { display: grid; gap: 12px; max-width: 1050px; }
.source-directory h2 { margin: 52px 0 6px; font-size: 34px; }
.source-directory .parts-callout { margin: 0; }
.law-facts.light > div { background: #fff; color: var(--ink); border-color: var(--line); }
.law-facts.light span { color: var(--muted); }

@media (max-width: 1050px) {
  .library-grid, .model-grid { grid-template-columns: 1fr 1fr; }
  .manual-callout, .parts-callout, .sources-band { grid-template-columns: 1fr; }
  .risk-grid { grid-template-columns: 1fr; }
}

@media (max-width: 760px) {
  .site-header { flex-wrap: wrap; padding-block: 13px; }
  .menu-button { display: block; }
  .site-header nav { display: none; flex-basis: 100%; flex-direction: column; gap: 0; padding: 13px 0 4px; }
  .site-header nav[data-open="true"] { display: flex; }
  .site-header nav a { padding: 12px 0; border-top: 1px solid var(--line); }
  .page-shell, .article-shell { padding-bottom: 88px; }
  .page-hero, .article-hero { padding: 76px 0 54px; }
  .article-meta, .library-grid, .model-grid { grid-template-columns: 1fr; }
  .quick-take { grid-template-columns: 1fr; gap: 10px; }
  .check-list { grid-template-columns: 1fr; }
  .manual-callout, .parts-callout { align-items: start; }
  .source-pill, .parts-directory article { grid-template-columns: 1fr; }
  .filter-panel { position: static; }
  .filter-row { grid-template-columns: 1fr; }
  .filter-row button { min-height: 48px; }
  .sources-band { gap: 32px; padding-top: 80px; padding-bottom: 80px; }
}