:root {
  --canvas: #eeece6;
  --paper: #fffefb;
  --ink: #20231f;
  --muted: #686e69;
  --rule: #d5d2ca;
  --rule-soft: #e9e6df;
  --accent: #2c5042;
  --accent-dark: #213d34;
  --accent-soft: #e7eee9;
  --warm: #9a5a2b;
  --warm-soft: #f3e9dd;
  --max: 1160px;
  --content: 1040px;
  --bar-height: 58px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--canvas);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
button { font: inherit; }

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 1000;
  padding: 9px 13px;
  color: #fff;
  background: var(--accent-dark);
  transform: translateY(-150%);
}

.skip-link:focus { transform: translateY(0); }

.site-bar {
  position: sticky;
  top: 0;
  z-index: 100;
  min-height: var(--bar-height);
  border-bottom: 1px solid var(--rule);
  background: rgba(238, 236, 230, 0.95);
  backdrop-filter: blur(14px);
}

.site-bar-inner {
  width: min(calc(100% - 36px), var(--max));
  min-height: var(--bar-height);
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 26px;
}

.brand {
  flex: 0 0 auto;
  color: var(--ink);
  font-size: 14px;
  font-weight: 680;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.brand:hover { text-decoration: none; }
.brand span { margin-right: 7px; color: var(--accent); font-family: Georgia, serif; font-size: 17px; }

.top-nav {
  display: flex;
  align-items: stretch;
  gap: 22px;
  margin-left: auto;
  overflow-x: auto;
  scrollbar-width: none;
}

.top-nav::-webkit-scrollbar { display: none; }

.top-nav a,
.home-link {
  position: relative;
  display: flex;
  align-items: center;
  min-height: var(--bar-height);
  color: #5c625d;
  font-size: 12px;
  font-weight: 620;
  white-space: nowrap;
}

.top-nav a::after {
  content: "";
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 150ms ease;
}

.top-nav a:hover,
.top-nav a.is-current,
.home-link:hover { color: var(--ink); text-decoration: none; }
.top-nav a:hover::after,
.top-nav a.is-current::after { transform: scaleX(1); }

.home-link {
  min-height: 0;
  padding-left: 20px;
  border-left: 1px solid var(--rule);
}

.document {
  width: min(calc(100% - 40px), var(--max));
  margin: 30px auto 0;
  padding: 58px 60px 90px;
  border: 1px solid var(--rule);
  background: var(--paper);
}

.intro {
  max-width: var(--content);
  margin: 0 auto;
}

.breadcrumb {
  margin: 0 0 17px;
  color: var(--accent);
  font-size: 12px;
  font-weight: 680;
  letter-spacing: 0.055em;
}

h1 {
  max-width: 900px;
  margin: 0;
  color: var(--ink);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(40px, 5.1vw, 66px);
  font-weight: 600;
  letter-spacing: -0.045em;
  line-height: 1.08;
}

.standfirst {
  max-width: 850px;
  margin: 24px 0 0;
  color: #4d544f;
  font-size: clamp(18px, 2vw, 22px);
  line-height: 1.62;
}

.recommendation-note {
  max-width: 920px;
  margin-top: 32px;
  padding: 18px 22px;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
  color: #35453e;
}

.recommendation-note strong { color: var(--accent-dark); }

.intro-meta {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin: 36px 0 0;
  padding: 18px 0;
  border-top: 1px solid var(--rule);
  border-bottom: 1px solid var(--rule);
}

.intro-meta div { padding: 0 18px; border-right: 1px solid var(--rule); }
.intro-meta div:first-child { padding-left: 0; }
.intro-meta div:last-child { border-right: 0; }
.intro-meta dt { margin-bottom: 3px; color: var(--muted); font-size: 11px; font-weight: 680; text-transform: uppercase; letter-spacing: 0.055em; }
.intro-meta dd { margin: 0; font-size: 13px; font-weight: 620; }

.section-tabs {
  max-width: var(--content);
  margin: 42px auto 0;
  display: flex;
  gap: 26px;
  overflow-x: auto;
  border-bottom: 1px solid var(--rule);
  scrollbar-width: none;
}

.section-tabs::-webkit-scrollbar { display: none; }
.section-tabs a { flex: 0 0 auto; padding: 0 0 11px; color: var(--muted); font-size: 12px; font-weight: 650; }
.section-tabs a:hover { color: var(--accent); text-decoration: none; }

.content-section {
  max-width: var(--content);
  margin: 0 auto;
  padding-top: 72px;
}

.content-section + .content-section { margin-top: 72px; border-top: 1px solid var(--rule); }

.section-title {
  display: grid;
  grid-template-columns: 44px 1fr;
  gap: 16px;
  align-items: start;
  margin-bottom: 30px;
}

.section-title > span {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  color: #fff;
  background: var(--accent);
  font-family: Georgia, serif;
  font-size: 15px;
}

.section-title h2 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(28px, 3vw, 38px);
  font-weight: 600;
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.section-title p { margin: 7px 0 0; color: var(--muted); font-size: 14px; }

.summary-table { border-top: 1px solid var(--rule); }

.summary-row {
  display: grid;
  grid-template-columns: 170px 1fr;
  gap: 28px;
  padding: 24px 0;
  border-bottom: 1px solid var(--rule);
}

.summary-row > div:first-child { display: flex; flex-direction: column; gap: 5px; }
.summary-row > div:first-child strong { color: var(--accent); font-size: 14px; }
.summary-row > div:first-child span { color: var(--muted); font-size: 11px; }
.summary-row h3 { margin: 0 0 5px; font-size: 17px; }
.summary-row p { margin: 0; color: var(--muted); font-size: 14px; }

.subheading {
  margin: 42px 0 18px;
  font-size: 20px;
  letter-spacing: -0.015em;
}

.research-loop {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  margin: 0;
  padding: 1px;
  background: var(--rule);
  list-style: none;
}

.research-loop li { min-height: 150px; padding: 18px; background: var(--paper); }
.research-loop span { display: block; margin-bottom: 22px; color: var(--warm); font-family: Georgia, serif; font-size: 14px; }
.research-loop strong { display: block; margin-bottom: 6px; font-size: 14px; }
.research-loop small { display: block; color: var(--muted); font-size: 11px; line-height: 1.5; }

.plain-note {
  margin: 18px 0 0;
  padding: 14px 18px;
  color: #515852;
  border: 1px solid var(--rule);
  background: #faf9f5;
  font-size: 13px;
}

.prose-columns {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 34px;
}

.prose-columns h3 { margin: 0 0 10px; font-size: 17px; line-height: 1.4; }
.prose-columns p { margin: 0; color: var(--muted); font-size: 14px; }

.caution-box {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 24px;
  margin-top: 30px;
  padding: 20px 22px;
  border: 1px solid #dfcab8;
  background: var(--warm-soft);
}

.caution-box strong { color: #77451f; font-size: 13px; }
.caution-box p { margin: 0; color: #634e3f; font-size: 14px; }

.table-scroll { overflow-x: auto; border: 1px solid var(--rule); }

.guide-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  font-size: 13px;
  line-height: 1.55;
}

.guide-table th,
.guide-table td { padding: 14px 15px; text-align: left; vertical-align: top; border-right: 1px solid var(--rule-soft); border-bottom: 1px solid var(--rule); }
.guide-table th:last-child,
.guide-table td:last-child { border-right: 0; }
.guide-table tbody tr:last-child td { border-bottom: 0; }
.guide-table thead th { color: #48514c; background: #f1f0eb; font-size: 11px; font-weight: 720; letter-spacing: 0.025em; }
.guide-table tbody tr:hover td { background: #fbfaf6; }

.build-table { min-width: 960px; }
.build-table th:nth-child(1) { width: 78px; }
.build-table th:nth-child(2) { width: 250px; }
.build-table th:nth-child(3) { width: 170px; }
.recommended-row td { background: #f5f8f5; }
.table-status { color: var(--muted); font-size: 10px; white-space: nowrap; }

.ranked-list { margin: 0; padding: 0; border-top: 1px solid var(--rule); list-style: none; }
.ranked-list li { display: grid; grid-template-columns: 54px 1fr; gap: 20px; padding: 22px 0; border-bottom: 1px solid var(--rule); }
.rank { color: var(--warm); font-family: Georgia, serif; font-size: 25px; }
.ranked-list h3 { margin: 0 0 5px; font-size: 17px; }
.ranked-list p { margin: 0; color: var(--muted); font-size: 14px; }

.catalogue-table { min-width: 980px; }
.catalogue-table th:nth-child(1) { width: 205px; }
.catalogue-table th:nth-child(3) { width: 225px; }
.catalogue-table th:nth-last-child(-n + 2) { width: 72px; text-align: center; }
.catalogue-table td:nth-last-child(-n + 2) { text-align: center; font-family: Georgia, serif; font-size: 15px; }
.catalogue-table td small { display: block; margin-top: 3px; color: var(--muted); font-size: 10px; }
.catalogue-table .group-row th { padding: 10px 14px; color: var(--accent); background: var(--accent-soft); border-bottom: 1px solid #ccd9d1; font-size: 11px; text-transform: uppercase; letter-spacing: 0.055em; }

.requirements-list { border-top: 1px solid var(--rule); }
.requirements-list article { display: grid; grid-template-columns: 54px 1fr; gap: 20px; padding: 22px 0; border-bottom: 1px solid var(--rule); }
.requirements-list article > span { color: var(--warm); font-family: Georgia, serif; font-size: 18px; }
.requirements-list h3 { margin: 0 0 5px; font-size: 17px; }
.requirements-list p { max-width: 790px; margin: 0; color: var(--muted); font-size: 14px; }

.prototype-grid { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 24px; margin-bottom: 24px; }
.specification-box,
.output-list { padding: 22px; border: 1px solid var(--rule); background: #faf9f5; }
.box-heading { display: flex; align-items: center; justify-content: space-between; gap: 18px; }
.box-heading h3,
.output-list h3 { margin: 0 0 16px; font-size: 16px; }

.copy-button { padding: 5px 10px; color: var(--accent); border: 1px solid var(--rule); background: #fff; font-size: 11px; font-weight: 680; cursor: pointer; }
.copy-button:hover { border-color: var(--accent); }

pre {
  margin: 0;
  padding: 16px 18px;
  overflow-x: auto;
  color: #e7ece9;
  background: var(--accent-dark);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 12px;
  line-height: 1.75;
  white-space: pre-wrap;
}

.copy-status { min-height: 17px; margin: 7px 0 0; color: var(--accent); font-size: 11px; }
.output-list ol { margin: 0; padding-left: 22px; }
.output-list li { padding: 5px 0 5px 6px; color: #4f5651; border-bottom: 1px solid var(--rule-soft); font-size: 13px; }
.output-list li:last-child { border-bottom: 0; }

.scope-table th { width: 33.333%; }
.scope-table ul { margin: 0; padding-left: 17px; }
.scope-table li { margin: 5px 0; }

.not-first-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  margin: 0;
  padding: 0;
  border-top: 1px solid var(--rule);
  list-style: none;
}

.not-first-list li { position: relative; padding: 16px 22px 16px 28px; border-bottom: 1px solid var(--rule); color: #535a55; font-size: 14px; }
.not-first-list li:nth-child(odd) { border-right: 1px solid var(--rule); }
.not-first-list li::before { content: "×"; position: absolute; left: 4px; color: var(--warm); font-weight: 700; }

.final-order { margin: 22px 0 0; padding: 18px 20px; color: #33463e; border-left: 4px solid var(--accent); background: var(--accent-soft); }

.reference-list { margin: 0; padding: 0; border-top: 1px solid var(--rule); list-style: none; }
.reference-list li { display: grid; grid-template-columns: 130px 1fr; gap: 2px 20px; padding: 14px 0; border-bottom: 1px solid var(--rule); }
.reference-list li > span { grid-row: 1 / span 2; color: var(--warm); font-size: 10px; font-weight: 680; text-transform: uppercase; letter-spacing: 0.035em; }
.reference-list a { color: var(--ink); font-size: 13px; font-weight: 650; }
.reference-list small { color: var(--muted); font-size: 10px; }

.footer {
  width: min(calc(100% - 40px), var(--max));
  margin: 0 auto;
  padding: 30px 0 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  color: var(--muted);
  font-size: 12px;
}

.footer p { margin: 0; }
.footer strong { color: var(--ink); }
.footer > a { font-weight: 650; }

:focus-visible { outline: 3px solid #bf7b49; outline-offset: 3px; }

@media (max-width: 900px) {
  .top-nav { display: none; }
  .home-link { margin-left: auto; }
  .document { padding-inline: 38px; }
  .research-loop { grid-template-columns: repeat(2, 1fr); }
  .prose-columns { grid-template-columns: 1fr; gap: 24px; }
  .prototype-grid { grid-template-columns: 1fr; }
}

@media (max-width: 640px) {
  html { scroll-padding-top: 78px; }
  .site-bar-inner { width: calc(100% - 28px); }
  .brand { overflow: hidden; text-overflow: ellipsis; }
  .home-link { padding-left: 14px; }
  .document { width: 100%; margin: 0; padding: 38px 20px 64px; border-right: 0; border-left: 0; }
  h1 { font-size: 40px; }
  .standfirst { font-size: 17px; }
  .recommendation-note { padding: 16px 17px; }
  .intro-meta { grid-template-columns: repeat(2, 1fr); }
  .intro-meta div { padding: 11px 12px; border-bottom: 1px solid var(--rule); }
  .intro-meta div:nth-child(2) { border-right: 0; }
  .intro-meta div:nth-last-child(-n + 2) { border-bottom: 0; }
  .intro-meta div:nth-child(3) { padding-left: 0; }
  .content-section { padding-top: 56px; }
  .content-section + .content-section { margin-top: 56px; }
  .section-title { grid-template-columns: 36px 1fr; gap: 12px; }
  .section-title > span { width: 30px; height: 30px; }
  .summary-row { grid-template-columns: 1fr; gap: 10px; }
  .summary-row > div:first-child { flex-direction: row; align-items: baseline; gap: 10px; }
  .research-loop { grid-template-columns: 1fr; }
  .research-loop li { min-height: 128px; }
  .caution-box { grid-template-columns: 1fr; gap: 7px; }
  .not-first-list { grid-template-columns: 1fr; }
  .not-first-list li:nth-child(odd) { border-right: 0; }
  .reference-list li { grid-template-columns: 1fr; gap: 3px; }
  .reference-list li > span { grid-row: auto; }
  .footer { width: calc(100% - 36px); align-items: flex-start; }
}

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

@media print {
  .site-bar,
  .section-tabs,
  .copy-button,
  .footer { display: none !important; }
  body { background: #fff; }
  .document { width: 100%; margin: 0; padding: 0; border: 0; }
  .content-section { break-inside: avoid; }
  .table-scroll { overflow: visible; }
  .guide-table { min-width: 0; font-size: 9px; }
}