:root {
  --ink: #111111;
  --muted: #4a4a4a;
  --line: #c4c4c4;
  --line-strong: #8a8a8a;
  --panel: #f2f2f2;
  --panel-light: #f7f7f7;
  --bg: #ffffff;
  --max-width: 980px;
  --section-gap: 36px;
  --body-gap: 20px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "IBM Plex Sans", "Source Sans 3", "Noto Sans", "Liberation Sans", "Helvetica Neue", Helvetica, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.5;
}

a { color: inherit; text-decoration: underline; }

header.chrome { border-bottom: 1px solid var(--line); background: var(--panel-light); }

.topbar {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 20px;
  justify-content: space-between;
  align-items: center;
  font-size: 0.88rem;
  color: var(--muted);
}

.topbar-brand { font-weight: 600; }

.topbar-brand a { text-decoration: none; }

.topbar-status { display: flex; flex-wrap: wrap; gap: 10px 18px; flex: 1 1 320px; }

.topbar-links { display: flex; flex-wrap: wrap; gap: 8px 14px; align-items: center; }

.primary-nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 10px 24px 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  font-size: 0.95rem;
}

.sub-nav {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 10px 24px 16px;
  border-top: 1px solid var(--line);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
  font-size: 0.9rem;
  color: var(--muted);
}

.sub-nav-label { font-size: 0.85rem; color: var(--muted); }

.sub-nav-list {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  padding: 0;
  margin: 0;
}

.sub-nav-list a[aria-current="page"] { font-weight: 600; text-decoration: none; }

main {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 24px 96px;
}

.section + .section {
  margin-top: var(--section-gap);
  padding-top: var(--section-gap);
  border-top: 1px solid var(--line);
}

.meta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 24px;
}

h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
  margin: 0 0 12px;
  font-weight: 600;
}

.lead { font-size: 1.05rem; margin: 0 0 8px; }
.subtle { font-size: 0.95rem; color: var(--muted); margin: 0; }

h2 { font-size: 1.35rem; margin: 0 0 16px; font-weight: 600; }
h3 { font-size: 1.05rem; margin: 0 0 12px; font-weight: 600; }

ul, ol { margin: 0; padding-left: 20px; }
li + li { margin-top: 8px; }

.two-col {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.narrow {
  max-width: 680px;
}

.stack { display: grid; gap: 16px; }

.panel {
  border: 1px solid var(--line);
  background: var(--panel-light);
  padding: 16px;
}

.panel-strong {
  border: 2px solid var(--line-strong);
  background: var(--panel);
  padding: 16px;
}

.diagram {
  margin-top: 16px;
  padding: 16px;
  border: 1px solid var(--line);
  background: var(--panel-light);
  font-family: "IBM Plex Mono", "Source Code Pro", "Liberation Mono", "Courier New", monospace;
  font-size: 0.9rem;
  white-space: pre;
  overflow-x: auto;
  max-width: 100%;
}

.boundary-stack { display: grid; gap: 16px; }

.boundary-block {
  border: 1px solid var(--line);
  background: var(--panel-light);
  padding: 18px;
}

.boundary-block.kernel {
  border: 2px solid var(--line-strong);
  background: var(--panel);
}

.note {
  margin-top: 12px;
  font-size: 0.9rem;
  color: var(--muted);
}

.steps {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 14px;
}

.steps li {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  align-items: start;
  border-bottom: 1px solid var(--line);
  padding-bottom: 12px;
}

.steps li:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.step-num {
  font-weight: 600;
  font-size: 1rem;
  color: var(--ink);
}

.step-text {
  margin: 0;
}

.equal-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.equal-block {
  border: 1px solid var(--line);
  padding: 16px;
  background: var(--panel-light);
}

.shared-output {
  margin-top: 20px;
  border: 1px solid var(--line);
  padding: 16px;
  background: var(--panel);
}

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

.audience-card {
  border: 1px solid var(--line);
  padding: 14px;
  background: var(--panel-light);
  min-height: 120px;
}

.utilitarian {
  font-size: 0.95rem;
  line-height: 1.4;
}

.doc-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: grid;
  gap: 12px;
}

.doc-item {
  border-bottom: 1px solid var(--line);
  padding-bottom: 10px;
}

.doc-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.optional-actions {
  border: 1px solid var(--line);
  padding: 16px;
  background: var(--panel-light);
  max-width: 520px;
}

.matrix,
.param-table,
.coverage-table,
.role-matrix,
.wallet-map,
.allocation-grid {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.matrix th,
.matrix td,
.param-table th,
.param-table td,
.coverage-table th,
.coverage-table td,
.role-matrix th,
.role-matrix td,
.wallet-map th,
.wallet-map td,
.allocation-grid th,
.allocation-grid td {
  border: 1px solid var(--line);
  padding: 10px 12px;
  text-align: left;
  vertical-align: top;
}

.matrix th,
.param-table th,
.coverage-table th,
.role-matrix th,
.wallet-map th,
.allocation-grid th { background: var(--panel-light); font-weight: 600; }

.definition-list {
  margin: 0;
}

.definition-list dt {
  font-weight: 600;
  margin-top: 12px;
}

.definition-list dd {
  margin: 4px 0 0 0;
  color: var(--muted);
}

.ladder {
  list-style: decimal;
  padding-left: 22px;
}

.ladder li {
  padding-left: 8px;
  border-left: 2px solid var(--line);
  margin-bottom: 10px;
}

.chain {
  list-style: decimal;
  padding-left: 22px;
}

.chain li {
  margin-bottom: 8px;
}

.status-block { font-size: 0.95rem; color: var(--muted); }

.tag {
  display: inline-block;
  border: 1px solid var(--line);
  padding: 4px 10px;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 18px;
}

.footer-note {
  margin-top: 18px;
  font-size: 0.85rem;
  color: var(--muted);
}

@media (max-width: 900px) {
  .audience-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 720px) {
  .two-col,
  .equal-grid { grid-template-columns: 1fr; }
  .audience-grid { grid-template-columns: 1fr; }
  .steps li { grid-template-columns: 36px 1fr; }
}