:root {
  --ink: #12181F;
  --ink-2: #3D4753;
  --ink-3: #5A6472;
  --ink-4: #6B7580;
  --muted: #8A94A1;
  --rule-numeral: #C2CCD9;
  --blue: #2B62AD;
  --blue-deep: #10294A;
  --blue-tint: #EDF2FA;
  --surface: #FFFFFF;
  --surface-2: #FAFBFC;
  --border: rgba(0,0,0,.09);
  --border-2: rgba(0,0,0,.07);
  --border-3: rgba(0,0,0,.11);
}

* {
  box-sizing: border-box;
}

html {
  font-family: "Public Sans", Arial, sans-serif;
  color: var(--ink);
  background: var(--surface);
}

body {
  margin: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  color: var(--blue);
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
}

.skip-link {
  position: absolute;
  top: 10px;
  left: 10px;
  z-index: 20;
  padding: 10px 12px;
  background: var(--surface);
  border: 1px solid var(--border-3);
  transform: translateY(-160%);
}

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

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 48px;
  padding: 18px 48px;
  border-bottom: 1px solid var(--border);
}

.wordmark {
  color: var(--blue-deep);
  font-size: 15px;
  font-weight: 800;
  line-height: 1;
  letter-spacing: .02em;
  text-transform: uppercase;
}

.top-nav {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--ink-2);
  font-size: 13.5px;
  font-weight: 500;
}

.home-hero {
  max-width: 700px;
  padding: 72px 48px 52px;
}

.eyebrow,
.section-label,
.meta,
.file-tag,
.small-meta {
  font-family: ui-monospace, Menlo, monospace;
}

.eyebrow {
  margin: 0 0 26px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1;
}

.home-hero h1 {
  margin: 0;
  color: var(--ink);
  font-size: 60px;
  font-weight: 300;
  line-height: 1.05;
}

.home-hero h1 em {
  color: var(--blue);
  font-style: italic;
  font-weight: 400;
}

.home-hero p:last-child {
  max-width: 620px;
  margin: 26px 0 0;
  color: var(--ink-2);
  font-size: 17.5px;
  line-height: 1.65;
  text-wrap: pretty;
}

.contents-list {
  border-top: 1px solid var(--border);
}

.contents-row {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr) auto;
  gap: 32px;
  align-items: center;
  min-height: 104px;
  padding: 30px 48px;
  border-bottom: 1px solid var(--border-2);
}

.contents-row:hover {
  background: var(--surface-2);
  color: inherit;
}

.contents-no {
  color: var(--rule-numeral);
  font-size: 44px;
  font-weight: 300;
  line-height: 1;
}

.contents-copy strong {
  display: block;
  margin-bottom: 8px;
  color: var(--ink);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.3;
}

.contents-copy span {
  display: block;
  max-width: 620px;
  color: var(--ink-2);
  font-size: 14px;
  line-height: 1.55;
}

.contents-meta {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  color: var(--muted);
  font-family: ui-monospace, Menlo, monospace;
  font-size: 12px;
  white-space: nowrap;
}

.contents-meta span {
  color: var(--blue);
  font-family: "Public Sans", Arial, sans-serif;
  font-size: 16px;
}

.resources-promo {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 26px;
  margin: 22px 48px 0;
  padding: 26px 30px;
  border-radius: 7px;
  background: var(--blue-tint);
}

.resources-promo h2 {
  margin: 0 0 8px;
  color: var(--blue-deep);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.3;
}

.resources-promo p {
  margin: 0;
  color: var(--ink-2);
  font-size: 14px;
  line-height: 1.5;
}

.button,
.action-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 36px;
  border-radius: 5px;
  font-size: 14px;
  font-weight: 600;
  line-height: 1;
}

.button {
  padding: 0 16px;
  background: var(--blue);
  color: var(--surface);
}

.button:hover {
  color: var(--surface);
}

.site-footer {
  margin-top: 22px;
  padding: 20px 48px;
  border-top: 1px solid var(--border);
  color: var(--ink-4);
  font-size: 12.5px;
  line-height: 1.4;
}

.chapter-shell {
  display: grid;
  grid-template-columns: 264px minmax(0, 1fr);
  min-height: calc(100vh - 90px);
}

.chapter-nav {
  position: sticky;
  top: 0;
  align-self: start;
  min-height: calc(100vh - 49px);
  padding: 36px 26px;
  border-right: 1px solid var(--border);
  background: var(--surface-2);
}

.back-link {
  display: inline-block;
  margin-bottom: 26px;
  color: var(--blue);
  font-size: 13px;
  font-weight: 500;
}

.chapter-nav a:not(.back-link) {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 9px;
  align-items: center;
  min-height: 44px;
  padding: 9px 11px;
  border-radius: 5px;
  color: var(--ink-2);
  font-size: 13px;
}

.chapter-nav a:not(.back-link):hover {
  background: #EEF1F5;
  color: var(--ink);
}

.chapter-nav a[aria-current="page"] {
  color: var(--ink);
  font-weight: 600;
}

.chapter-nav .nav-no {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 12px;
  font-weight: 500;
  line-height: 1.6;
}

.article-wrap {
  padding: 56px;
}

.article,
.resources-page {
  max-width: 660px;
}

.meta {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1;
}

.article h1,
.resources-page h1 {
  margin: 0;
  color: var(--ink);
  font-size: 46px;
  font-weight: 300;
  line-height: 1.08;
}

.lede,
.resources-intro {
  margin: 24px 0 0;
  color: var(--ink-3);
  font-size: 19px;
  line-height: 1.6;
  text-wrap: pretty;
}

.article-rule {
  margin: 34px 0 30px;
  border: 0;
  border-top: 1px solid var(--border);
}

.article-section + .article-section {
  margin-top: 30px;
}

.article-section h2 {
  margin: 0 0 12px;
  font-size: 20px;
  font-weight: 700;
  line-height: 1.3;
}

.article-section p,
.article p {
  margin: 0;
  color: var(--ink-2);
  font-size: 16px;
  line-height: 1.7;
  text-wrap: pretty;
}

.article > .lede {
  margin-top: 24px;
  color: var(--ink-3);
  font-size: 19px;
  line-height: 1.6;
}

.article-section p + p {
  margin-top: 14px;
}

.article code {
  display: inline-block;
  padding: 1px 6px;
  border: 1px solid var(--border-2);
  border-radius: 4px;
  background: #f7fbff;
  color: var(--blue-deep);
  font-family: var(--mono);
  font-size: .88em;
  line-height: 1.45;
  white-space: nowrap;
}

.namespace-panel {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  overflow: hidden;
  margin: 26px 0 32px;
  padding: 0;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--border-2);
}

.namespace-item {
  min-width: 0;
  padding: 20px;
  background: var(--surface);
}

.namespace-item dt {
  display: block;
  margin: 0 0 10px;
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .08em;
  text-transform: uppercase;
}

.namespace-item dd {
  margin: 0;
}

.namespace-item dd p {
  margin: 9px 0 0;
  color: var(--ink-3);
  font-size: 13px;
  line-height: 1.45;
}

.namespace-item dd p code {
  display: inline;
  width: auto;
  padding: 0;
  border: 0;
  background: transparent;
}

.namespace-item code {
  display: block;
  width: 100%;
  padding: 10px 12px;
  overflow-wrap: anywhere;
  white-space: normal;
  border-color: rgba(43,98,173,.22);
  background: var(--blue-tint);
  color: var(--blue-deep);
  font-family: var(--mono);
  font-size: 14px;
  line-height: 1.4;
}

.atomic-diagram {
  margin: 32px 0;
}

.atomic-diagram figcaption {
  margin-bottom: 16px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 700;
}

.atomic-flow {
  position: relative;
  display: grid;
  gap: 0;
  margin: 0;
  padding: 0;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
  list-style: none;
}

.atomic-flow li {
  display: grid;
  grid-template-columns: 56px minmax(0, 1fr);
  gap: 16px;
  align-items: center;
  min-width: 0;
  padding: 18px 20px;
  background: linear-gradient(90deg, #f7faff, var(--surface) 42%);
}

.atomic-flow li + li {
  border-top: 1px solid var(--border-2);
}

.atomic-number {
  display: grid;
  width: 44px;
  height: 44px;
  place-items: center;
  border: 1px solid rgba(43,98,173,.25);
  border-radius: 50%;
  background: var(--blue-tint);
  color: var(--blue-deep);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
}

.atomic-content {
  min-width: 0;
}

.atomic-content strong {
  display: block;
  margin-bottom: 4px;
  color: var(--ink);
  font-size: 16px;
  line-height: 1.3;
}

.atomic-content p {
  margin: 0;
  font-size: 14px;
  line-height: 1.5;
}

.decision-rights {
  display: grid;
  margin: 24px 0 32px;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.decision-rights > div {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 20px;
  align-items: start;
  padding: 18px 20px;
}

.decision-rights > div + div {
  border-top: 1px solid var(--border-2);
}

.decision-rights span {
  color: var(--blue-deep);
  font-size: 14px;
  font-weight: 700;
  line-height: 1.5;
}

.decision-rights p {
  font-size: 14px;
  line-height: 1.55;
}

.governance-lifecycle {
  display: grid;
  gap: 0;
  margin: 24px 0 32px;
  padding: 0;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
  list-style: none;
}

.governance-lifecycle li {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  min-width: 0;
  padding: 16px 20px;
}

.governance-lifecycle li + li {
  border-top: 1px solid var(--border-2);
}

.governance-lifecycle li > span {
  display: grid;
  width: 40px;
  height: 40px;
  place-items: center;
  border: 1px solid rgba(43,98,173,.2);
  border-radius: 50%;
  background: var(--blue-tint);
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
}

.governance-lifecycle strong {
  display: block;
  margin: 1px 0 4px;
  color: var(--ink);
  font-size: 14px;
}

.governance-lifecycle p {
  font-size: 13.5px;
  line-height: 1.5;
}

.token-tiers {
  display: grid;
  gap: 10px;
  margin: 26px 0 34px;
}

.token-tier {
  display: grid;
  grid-template-columns: 54px minmax(0, 1fr);
  gap: 6px 16px;
  align-items: start;
  min-width: 0;
  padding: 18px 20px;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.token-tier-number {
  display: grid;
  grid-row: 1 / span 3;
  width: 40px;
  height: 40px;
  place-items: center;
  border: 1px solid rgba(43,98,173,.2);
  border-radius: 50%;
  background: var(--blue-tint);
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
}

.token-tier h3 {
  margin: 1px 0 0;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.3;
}

.token-tier p {
  margin: 0 0 6px;
  font-size: 13.5px;
  line-height: 1.5;
}

.token-tier code {
  display: block;
  width: fit-content;
  max-width: 100%;
  padding: 7px 9px;
  overflow-wrap: anywhere;
  font-size: 11px;
  white-space: normal;
}

.token-chain {
  display: grid;
  margin: 24px 0 34px;
  padding: 0;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
  list-style: none;
}

.token-chain li {
  position: relative;
  display: grid;
  grid-template-columns: 90px minmax(0, 1fr);
  gap: 6px 18px;
  align-items: center;
  padding: 16px 20px;
}

.token-chain li + li {
  border-top: 1px solid var(--border-2);
}

.token-chain li + li::before {
  position: absolute;
  top: -9px;
  left: 44px;
  width: 16px;
  height: 16px;
  border-right: 1px solid var(--border-3);
  border-bottom: 1px solid var(--border-3);
  background: var(--surface);
  content: "";
  transform: rotate(45deg);
}

.token-chain span {
  grid-row: 1 / span 2;
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.token-chain code {
  width: fit-content;
  max-width: 100%;
  overflow-wrap: anywhere;
  white-space: normal;
}

.token-chain p {
  font-size: 13px;
  line-height: 1.45;
}

.naming-patterns {
  display: grid;
  margin: 24px 0 34px;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.naming-patterns > div {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr);
  gap: 8px 16px;
  padding: 18px 20px;
}

.naming-patterns > div + div {
  border-top: 1px solid var(--border-2);
}

.naming-patterns span {
  grid-row: 1 / span 2;
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.naming-patterns code {
  width: fit-content;
  max-width: 100%;
  overflow-wrap: anywhere;
  white-space: normal;
}

.naming-patterns p {
  font-size: 12.5px;
  line-height: 1.4;
}

.theme-map {
  display: grid;
  margin: 24px 0 34px;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.theme-map-row {
  display: grid;
  grid-template-columns: 1.55fr 1fr 1fr;
}

.theme-map-row + .theme-map-row {
  border-top: 1px solid var(--border-2);
}

.theme-map-row > * {
  min-width: 0;
  padding: 12px 14px;
}

.theme-map-row > * + * {
  border-left: 1px solid var(--border-2);
}

.theme-map-head {
  background: #f7faff;
  color: var(--ink-4);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.theme-map code {
  display: block;
  padding: 12px 14px;
  overflow-wrap: anywhere;
  border: 0;
  background: transparent;
  color: var(--ink-2);
  font-size: 12px;
  white-space: normal;
}

.code-example {
  margin: 24px 0 34px;
  padding: 20px;
  overflow-x: auto;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: #111b26;
  color: #e9f2fb;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
}

.code-example code {
  display: block;
  padding: 0;
  border: 0;
  background: transparent;
  color: inherit;
  font: inherit;
  white-space: pre;
}

.practice-list {
  display: grid;
  gap: 10px;
  margin: 18px 0 32px;
  padding-left: 22px;
  color: var(--ink-2);
}

.practice-list li {
  padding-left: 4px;
  font-size: 15px;
  line-height: 1.55;
}

.doc-history,
.ai-workflow {
  margin: 24px 0 34px;
  padding: 0;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  list-style: none;
}

.doc-history li {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  padding: 20px;
}

.doc-history li + li,
.ai-workflow li + li {
  border-top: 1px solid var(--border-2);
}

.doc-stage-no,
.doc-contract > div > span {
  color: #afbecf;
  font-family: var(--mono);
  font-size: 24px;
  line-height: 1;
}

.doc-history strong,
.doc-contract strong,
.implementation-boundary strong,
.ai-workflow strong,
.doc-source-model strong {
  display: block;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.35;
}

.doc-history p,
.doc-contract p,
.implementation-boundary p,
.ai-workflow p,
.doc-source-model p,
.article-note p {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.55;
}

.doc-source-model,
.implementation-boundary {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin: 24px 0 30px;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
}

.doc-source-model > div,
.implementation-boundary > div {
  min-width: 0;
  padding: 20px;
}

.doc-source-model > div + div,
.implementation-boundary > div + div {
  border-left: 1px solid var(--border-2);
}

.doc-source-model span {
  display: block;
  margin-bottom: 14px;
  color: var(--blue-deep);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
}

.article-note {
  margin: 24px 0 34px;
  padding: 18px 20px;
  border-left: 3px solid var(--blue);
  background: var(--blue-tint);
}

.article-note strong {
  color: var(--blue-deep);
  font-size: 14px;
}

.doc-contract {
  margin: 24px 0 30px;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
}

.doc-contract > div {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  padding: 18px 20px;
}

.doc-contract > div + div {
  border-top: 1px solid var(--border-2);
}

.ai-workflow li {
  display: grid;
  grid-template-columns: 34px 142px minmax(0, 1fr);
  gap: 14px;
  align-items: center;
  padding: 16px 20px;
}

.ai-workflow li > span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--blue-tint);
  color: var(--blue-deep);
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 700;
}

.ai-workflow p {
  margin: 0;
}

.source-section {
  padding-top: 4px;
}

.source-section > a {
  display: block;
  padding: 14px 0;
  border-top: 1px solid var(--border-2);
}

.source-section > a:last-child {
  border-bottom: 1px solid var(--border-2);
}

.source-section > a strong,
.source-section > a span {
  display: block;
}

.source-section > a strong {
  color: var(--blue-deep);
  font-size: 14px;
}

.source-section > a span {
  margin-top: 4px;
  color: var(--ink-4);
  font-size: 13px;
  line-height: 1.5;
}

.pullquote {
  margin: 34px 0;
  padding-left: 20px;
  border-left: 3px solid var(--blue);
  color: var(--blue-deep);
  font-size: 19px;
  font-style: italic;
  line-height: 1.6;
}

.file-panel {
  margin: 34px 0 30px;
  padding: 24px 26px;
  border-radius: 7px;
  background: var(--blue-tint);
}

.section-label {
  margin: 0 0 14px;
  color: var(--blue-deep);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .09em;
  line-height: 1;
  text-transform: uppercase;
}

.file-row {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr) auto;
  gap: 16px;
  align-items: center;
  min-height: 52px;
}

.file-row + .file-row {
  margin-top: 8px;
}

.file-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 22px;
  border: 1px solid rgba(16,41,74,.15);
  border-radius: 4px;
  background: var(--surface);
  color: var(--blue-deep);
  font-size: 9.5px;
  font-weight: 700;
}

.file-name {
  display: block;
  color: var(--ink);
  font-size: 14.5px;
  font-weight: 600;
  line-height: 1.35;
}

.small-meta {
  display: block;
  margin-top: 2px;
  color: var(--ink-4);
  font-size: 12.5px;
  line-height: 1.4;
}

.file-action {
  color: var(--blue);
  font-size: 13px;
  font-weight: 600;
}

.next-card {
  display: block;
  margin-top: 32px;
  padding: 22px 24px;
  border: 1px solid var(--border-3);
  border-radius: 7px;
}

.next-card:hover,
.resource-card:hover {
  border-color: var(--blue);
  color: inherit;
}

.next-card strong {
  display: block;
  margin: 10px 0 7px;
  font-size: 17px;
  line-height: 1.3;
}

.next-card span:last-child {
  display: block;
  color: var(--ink-2);
  font-size: 13.5px;
  line-height: 1.5;
}

.resources-main {
  padding: 48px;
}

.resources-page {
  max-width: 620px;
}

.resource-section {
  margin-top: 40px;
}

.empty-note {
  max-width: 620px;
  margin: 0;
  padding: 18px 0;
  border-top: 1px solid var(--border-2);
  border-bottom: 1px solid var(--border-2);
  color: var(--ink-4);
  font-size: 14.5px;
  line-height: 1.6;
}

.figma-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  max-width: 900px;
}

.resource-card {
  display: block;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.cover {
  min-height: 120px;
  border-bottom: 1px solid var(--border);
  background:
    repeating-linear-gradient(135deg, rgba(43,98,173,.08) 0 6px, transparent 6px 12px),
    linear-gradient(180deg, #f8fbff, var(--blue-tint));
}

.cover-strategy {
  background:
    linear-gradient(90deg, rgba(18,24,31,.08) 1px, transparent 1px) 0 0 / 18px 18px,
    linear-gradient(180deg, #fbfdff, var(--blue-tint));
}

.cover-specs {
  background:
    linear-gradient(90deg, transparent 22px, rgba(43,98,173,.11) 22px 24px, transparent 24px) 0 0 / 72px 100%,
    linear-gradient(180deg, transparent 30px, rgba(18,24,31,.07) 30px 31px, transparent 31px) 0 0 / 100% 46px,
    linear-gradient(180deg, #fbfdff, var(--blue-tint));
}

.cover-image {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-bottom: 1px solid var(--border);
  background: var(--blue-tint);
}

.card-body {
  padding: 16px 17px 17px;
}

.card-body strong {
  display: block;
  margin-bottom: 6px;
  font-size: 15px;
  font-weight: 600;
}

.card-body .button {
  margin-top: 14px;
  min-height: 32px;
  font-size: 13px;
}

.button-disabled {
  border: 1px solid rgba(16,41,74,.15);
  background: var(--surface-2);
  color: var(--ink-4);
}

.button-disabled:hover {
  color: var(--ink-4);
}

.resource-columns {
  display: flex;
  gap: 40px;
  align-items: flex-start;
  margin-top: 40px;
}

.resource-list {
  flex: 1 1 420px;
}

.standards {
  flex: 0 1 320px;
}

.resource-list .file-row {
  padding: 14px 0;
  border-top: 1px solid var(--border-2);
}

.resource-list .file-row:last-child {
  border-bottom: 1px solid var(--border-2);
}

.resource-list .file-tag {
  min-height: 24px;
  background: var(--blue-tint);
}

.action-button {
  padding: 0 13px;
  border: 1px solid rgba(43,98,173,.4);
  color: var(--blue);
  font-size: 13px;
}

.standard-link {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 10px;
  padding: 12px 16px;
  border-radius: 5px;
  background: var(--blue-tint);
  color: var(--blue-deep);
  font-size: 13.5px;
  font-weight: 600;
}

.learning-main {
  padding: 56px 48px 72px;
}

.learning-hero {
  max-width: 700px;
  padding-bottom: 52px;
  border-bottom: 1px solid var(--border);
}

.learning-hero h1 {
  margin: 0;
  color: var(--ink);
  font-size: 54px;
  font-weight: 300;
  line-height: 1.06;
}

.learning-section {
  max-width: 980px;
  padding-top: 48px;
}

.learning-heading {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 36px;
  align-items: start;
  margin-bottom: 24px;
}

.learning-heading h2 {
  margin: 0;
  max-width: 680px;
  color: var(--ink);
  font-size: 30px;
  font-weight: 300;
  line-height: 1.18;
}

.layer-stack {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border: 1px solid var(--border-3);
  border-radius: 7px;
  overflow: hidden;
}

.layer-stack article {
  min-height: 220px;
  padding: 22px;
  border-right: 1px solid var(--border-2);
  background: var(--surface);
}

.layer-stack article:last-child {
  border-right: 0;
}

.layer-stack span,
.setup-roadmap span {
  display: inline-block;
  margin-bottom: 22px;
  color: var(--rule-numeral);
  font-size: 34px;
  font-weight: 300;
  line-height: 1;
}

.setup-roadmap span {
  grid-row: 1 / span 2;
  margin-bottom: 0;
}

.layer-stack strong {
  display: block;
  margin-bottom: 10px;
  color: var(--ink);
  font-size: 17px;
  line-height: 1.3;
}

.layer-stack p,
.setup-roadmap p,
.responsibility-grid p,
.deliverable-pair li {
  margin: 0;
  color: var(--ink-2);
  font-size: 14.5px;
  line-height: 1.65;
  text-wrap: pretty;
}

.setup-roadmap {
  display: grid;
  gap: 1px;
  border: 1px solid var(--border-2);
  border-radius: 7px;
  overflow: hidden;
  background: var(--border-2);
}

.setup-roadmap article {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  column-gap: 24px;
  row-gap: 8px;
  align-items: start;
  padding: 22px 24px;
  background: var(--surface);
}

.setup-roadmap p {
  grid-column: 2;
  max-width: 720px;
}

.setup-roadmap h3,
.deliverable-pair h3 {
  margin: 0;
  color: var(--ink);
  font-size: 17px;
  font-weight: 700;
  line-height: 1.3;
}

.responsibility-grid {
  display: grid;
  grid-template-columns: .8fr 1fr 1fr;
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--border-2);
}

.responsibility-grid > div {
  min-height: 100px;
  padding: 16px;
  background: var(--surface);
}

.responsibility-grid .grid-head {
  min-height: auto;
  background: var(--blue-deep);
  color: var(--surface);
  font-size: 13.5px;
  font-weight: 700;
}

.responsibility-grid strong {
  display: block;
  margin-bottom: 8px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.3;
}

.code-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.code-card {
  overflow: hidden;
  border: 1px solid var(--border-3);
  border-radius: 7px;
  background: var(--surface);
}

.code-card-header {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 18px;
  border-bottom: 1px solid var(--border-2);
}

.code-card-header strong {
  color: var(--ink);
  font-size: 15px;
  line-height: 1.3;
}

.code-card-header span {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.5;
  text-align: right;
}

.code-card pre {
  min-height: 260px;
  margin: 0;
  padding: 18px;
  overflow-x: auto;
  background: #0d1724;
  color: #eef5ff;
  font-family: var(--mono);
  font-size: 12px;
  line-height: 1.65;
}

.code-note {
  max-width: 760px;
  margin: 18px 0 0;
  color: var(--ink-2);
  font-size: 15px;
  line-height: 1.7;
}

.deliverable-pair {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.deliverable-pair article {
  padding: 24px;
  border: 1px solid var(--border-3);
  border-radius: 7px;
}

.deliverable-pair ul {
  display: grid;
  gap: 10px;
  margin: 18px 0 0;
  padding-left: 20px;
}

@media (max-width: 899px) {

  .site-header,
  .home-hero,
  .contents-row,
  .resources-main,
  .site-footer {
    padding-left: 28px;
    padding-right: 28px;
  }

  .home-hero h1 {
    font-size: 44px;
  }

  .chapter-shell {
    display: block;
  }

  .chapter-nav {
    position: static;
    min-height: 0;
    border-right: 0;
    border-bottom: 1px solid var(--border);
  }

  .article-wrap {
    padding: 40px 28px;
  }

  .figma-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .resource-columns {
    display: block;
  }

  .standards {
    margin-top: 40px;
  }

  .resources-promo {
    margin-left: 28px;
    margin-right: 28px;
  }

  .learning-main {
    padding: 40px 28px 56px;
  }

  .learning-hero h1 {
    font-size: 44px;
  }

  .learning-heading {
    display: block;
  }

  .learning-heading .section-label {
    margin-bottom: 14px;
  }

  .layer-stack {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .layer-stack article:nth-child(2) {
    border-right: 0;
  }

  .layer-stack article {
    border-bottom: 1px solid var(--border-2);
  }

  .layer-stack article:nth-last-child(-n+2) {
    border-bottom: 0;
  }

  .setup-roadmap article {
    grid-template-columns: 52px minmax(0, 1fr);
    row-gap: 8px;
  }

  .setup-roadmap p {
    grid-column: 2;
  }

  .responsibility-grid {
    grid-template-columns: 1fr;
  }

  .responsibility-grid > div {
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: auto;
    padding: 16px;
  }

  .responsibility-grid p {
    line-height: 1.45;
  }

  .responsibility-grid .grid-head {
    display: none;
  }

  .code-grid {
    grid-template-columns: 1fr;
  }

  .code-card pre {
    min-height: auto;
  }

  .deliverable-pair {
    grid-template-columns: 1fr;
  }

  .doc-source-model,
  .implementation-boundary {
    grid-template-columns: 1fr;
  }

  .doc-source-model > div + div,
  .implementation-boundary > div + div {
    border-top: 1px solid var(--border-2);
    border-left: 0;
  }

  .ai-workflow li {
    grid-template-columns: 34px minmax(0, 1fr);
  }

  .ai-workflow p {
    grid-column: 2;
  }
}

@media (max-width: 639px) {

  .site-header {
    display: grid;
    gap: 14px;
    align-items: start;
    padding: 16px 20px;
  }

  .top-nav {
    justify-content: space-between;
    gap: 12px;
    width: 100%;
    font-size: 12px;
  }

  .home-hero,
  .resources-main {
    padding: 48px 20px 40px;
  }

  .home-hero h1 {
    font-size: 34px;
    line-height: 1.1;
  }

  .contents-row {
    grid-template-columns: 1fr;
    gap: 12px;
    padding: 24px 20px;
  }

  .contents-no {
    font-size: 28px;
  }

  .contents-meta {
    justify-content: space-between;
  }

  .resources-promo {
    display: block;
    margin: 20px;
    padding: 22px;
  }

  .resources-promo .button {
    margin-top: 18px;
  }

  .article h1,
  .resources-page h1 {
    font-size: 36px;
  }

  .figma-grid {
    grid-template-columns: 1fr;
  }

  .file-row {
    grid-template-columns: 48px minmax(0, 1fr);
  }

  .file-action,
  .action-button {
    grid-column: 2;
    justify-self: start;
  }

  .learning-main {
    padding: 40px 20px 48px;
  }

  .learning-hero h1 {
    font-size: 34px;
    line-height: 1.1;
  }

  .layer-stack {
    grid-template-columns: 1fr;
  }

  .layer-stack article,
  .layer-stack article:nth-child(2),
  .layer-stack article:nth-last-child(-n+2) {
    border-right: 0;
    border-bottom: 1px solid var(--border-2);
  }

  .layer-stack article:last-child {
    border-bottom: 0;
  }

  .setup-roadmap article {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  .setup-roadmap p {
    grid-column: auto;
  }

  .namespace-panel {
    grid-template-columns: 1fr;
  }

  .doc-history li,
  .doc-contract > div {
    grid-template-columns: 36px minmax(0, 1fr);
    gap: 12px;
    padding: 16px;
  }

  .doc-stage-no,
  .doc-contract > div > span {
    font-size: 19px;
  }

  .decision-rights > div {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .token-tiers {
    grid-template-columns: 1fr;
  }

  .token-tier {
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 6px 12px;
    padding: 16px;
  }

  .token-tier-number {
    width: 36px;
    height: 36px;
  }

  .token-chain li {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 6px 12px;
    padding: 15px 16px;
  }

  .token-chain li + li::before {
    left: 34px;
  }

  .naming-patterns > div {
    grid-template-columns: 1fr;
    gap: 7px;
    padding: 16px;
  }

  .naming-patterns span {
    grid-row: auto;
  }

  .theme-map-row > * {
    padding: 10px 8px;
  }

  .theme-map code {
    padding: 10px 8px;
    font-size: 11px;
  }

  .atomic-flow li {
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 12px;
    padding: 16px;
  }

  .atomic-number {
    width: 38px;
    height: 38px;
  }
}

/* Public playbook additions */
:root { --mono: ui-monospace, Menlo, monospace; }
.feature-link { display:inline-block; margin-top:16px; color:var(--blue); font-weight:700; text-decoration:underline; text-underline-offset:5px; }
.home-hero { max-width:850px; }
.demo-intro { font-size:15px; line-height:1.7; color:var(--ink-3); }
.demo-main { max-width:1050px; margin:auto; padding:64px 28px; }
.demo-main h1 { font-size:clamp(36px,6vw,60px); letter-spacing:-.045em; margin:16px 0; }
.demo-main h2 { margin-top:40px; }
.demo-main p, .demo-main li { line-height:1.7; }
.demo-main a:not(.feature-link) { text-decoration:underline; text-underline-offset:3px; }
.demo-controls { display:flex; flex-wrap:wrap; gap:20px; margin:24px 0; align-items:center; }
.demo-controls label { display:flex; gap:8px; align-items:center; }
.demo-controls select { padding:10px; font:inherit; border:1px solid var(--ink-3); border-radius:4px; background:white; color:#12181f; }
.demo-stage { border:1px solid var(--border-3); border-radius:12px; padding:32px; background:var(--ds-colour-background-primary); color:var(--ds-colour-text-primary); }
.demo-stage h2 { margin-top:0; }
.ds-button { min-height:44px; padding:12px 20px; font:inherit; font-weight:700; border:2px solid transparent; border-radius:6px; cursor:pointer; background:var(--ds-button-background-primary); color:var(--ds-button-label-primary); }
.ds-button:hover { background:var(--ds-button-background-primary-hover); }
.ds-button:focus-visible { outline:3px solid var(--ds-colour-focus); outline-offset:4px; }
.ds-button:disabled { background:var(--ds-colour-background-disabled); color:var(--ds-colour-text-disabled); cursor:not-allowed; }
.demo-status { min-height:1.7em; margin-bottom:0; }
.token-table-wrap { overflow-x:auto; }
.token-table { width:100%; border-collapse:collapse; font-size:14px; }
.token-table th, .token-table td { padding:14px 12px; border-bottom:1px solid var(--border-3); text-align:left; }
.token-table code { overflow-wrap:anywhere; }
.demo-columns { display:grid; grid-template-columns:1fr 1fr; gap:32px; }
@media(max-width:639px) { .demo-main { padding:40px 20px; } .demo-stage { padding:24px; } .demo-columns { grid-template-columns:1fr; gap:0; } .top-nav { flex-wrap:wrap; } }