:root {
  --ink: #1b2430;
  --muted: #5b6573;
  --line: #e2e6eb;
  --paper: #ffffff;
  --tint: #f5f7f9;
  --accent: #1f5f8b;
  --accent-ink: #ffffff;
  --risk: #b03a2e;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; font: 16px/1.6 var(--sans); color: var(--ink); background: var(--paper); }
a { color: var(--accent); text-decoration-thickness: 1px; text-underline-offset: 2px; }
img { max-width: 100%; height: auto; display: block; }
code { font-family: var(--mono); font-size: 0.88em; background: var(--tint); padding: 0.1em 0.35em; border-radius: 4px; }
pre { background: #0f1720; color: #e6edf3; padding: 1rem 1.2rem; border-radius: 8px; overflow-x: auto; line-height: 1.45; }
pre code { background: none; padding: 0; color: inherit; font-size: 0.82rem; }

.wrap { max-width: 1080px; margin: 0 auto; padding: 0 1.25rem; }

.topbar { position: sticky; top: 0; z-index: 10; background: rgba(255, 255, 255, 0.95); border-bottom: 1px solid var(--line); }
.topbar-inner { display: flex; align-items: center; justify-content: space-between; gap: 1rem; min-height: 56px; flex-wrap: wrap; }
.brand { font-weight: 700; color: var(--ink); text-decoration: none; font-family: var(--mono); }
.topbar nav { display: flex; gap: 1.1rem; flex-wrap: wrap; font-size: 0.92rem; }
.topbar nav a { color: var(--muted); text-decoration: none; }
.topbar nav a:hover, .topbar nav a.here { color: var(--ink); }

.hero { background: linear-gradient(180deg, var(--tint), var(--paper)); padding: 3.5rem 0 1.5rem; border-bottom: 1px solid var(--line); }
.hero-grid { display: grid; grid-template-columns: 1.05fr 1fr; gap: 2.5rem; align-items: center; }
.eyebrow { text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.78rem; font-weight: 600; color: var(--accent); margin: 0 0 0.5rem; }
h1 { font-size: 2.3rem; line-height: 1.15; margin: 0 0 1rem; letter-spacing: -0.01em; }
.lede { font-size: 1.08rem; color: var(--muted); margin: 0 0 1.5rem; }
.cta { display: flex; gap: 0.6rem; flex-wrap: wrap; }
.button { display: inline-block; padding: 0.55rem 1rem; border-radius: 6px; border: 1px solid var(--line); background: var(--paper); color: var(--ink); text-decoration: none; font-weight: 600; font-size: 0.95rem; }
.button.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); }
.hero-chart { margin: 0; background: var(--paper); border: 1px solid var(--line); border-radius: 10px; padding: 0.75rem; }
.hero-chart figcaption { font-size: 0.88rem; color: var(--muted); margin-top: 0.5rem; }

.tiles { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; margin: 2.5rem 0 0.75rem; }
.tile { border: 1px solid var(--line); border-radius: 10px; padding: 1rem 1.1rem; background: var(--paper); }
.tile dt { font-size: 0.82rem; color: var(--muted); }
.tile dd { margin: 0.2rem 0 0.1rem; font-size: 1.9rem; font-weight: 700; font-variant-numeric: tabular-nums; }
.tile p { margin: 0; font-size: 0.82rem; color: var(--muted); }
.tile.warn dd { color: var(--risk); }
.note { font-size: 0.86rem; color: var(--muted); }

.prose { padding-top: 2.75rem; }
.prose h2 { font-size: 1.6rem; margin: 0 0 0.9rem; padding-top: 0.5rem; border-top: 1px solid var(--line); }
.prose > h2:first-child { border-top: 0; }
.prose h3 { font-size: 1.15rem; margin: 1.8rem 0 0.6rem; }
.prose p, .prose li { max-width: 78ch; }
.prose table { border-collapse: collapse; width: 100%; margin: 1rem 0 1.5rem; font-size: 0.92rem; display: block; overflow-x: auto; }
.prose th, .prose td { border-bottom: 1px solid var(--line); padding: 0.45rem 0.7rem; text-align: left; vertical-align: top; }
.prose th { background: var(--tint); font-weight: 600; white-space: nowrap; }
.prose td { font-variant-numeric: tabular-nums; }
.prose figure { margin: 1.25rem 0; }
.prose figcaption { font-size: 0.86rem; color: var(--muted); margin-top: 0.4rem; }
.prose figure img { border: 1px solid var(--line); border-radius: 8px; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1.25rem; }
.callout { border-left: 4px solid var(--risk); background: #fbf3f2; padding: 0.8rem 1rem; border-radius: 0 6px 6px 0; }
.terminal { font-size: 0.82rem; }

.diagram { overflow-x: auto; border: 1px solid var(--line); border-radius: 10px; padding: 0.75rem; background: var(--paper); }
.diagram details { margin-top: 0.5rem; font-size: 0.86rem; color: var(--muted); }
.flowchart { display: block; width: 100%; max-width: 760px; height: auto; margin: 0 auto; }
.fc-node rect { fill: var(--tint); stroke: #9aa5b1; stroke-width: 1; }
.fc-node text { font: 12.5px var(--sans); fill: var(--ink); text-anchor: middle; }
.fc-edge { fill: none; stroke: #8b96a3; stroke-width: 1.2; }
.fc-arrow { fill: #8b96a3; }

.doc { padding-bottom: 2rem; }
.doc h1 { font-size: 2rem; margin-top: 0.5rem; }
.doc h2 { margin-top: 2.2rem; }
.crumb { font-size: 0.86rem; color: var(--muted); }

.footer { margin-top: 3.5rem; border-top: 1px solid var(--line); background: var(--tint); padding: 1.5rem 0; font-size: 0.86rem; color: var(--muted); }

@media (max-width: 860px) {
  .hero-grid, .grid2 { grid-template-columns: 1fr; }
  .tiles { grid-template-columns: repeat(2, 1fr); }
  h1 { font-size: 1.8rem; }
  .topbar { position: static; }
  .tile dd { font-size: 1.5rem; }
}