:root {
  color-scheme: light;
  --ink: #152019;
  --muted: #587064;
  --line: #d9e2dc;
  --panel: #f6f8f5;
  --accent: #0f766e;
  --accent-strong: #0b4f4a;
  --paper: #ffffff;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}

a {
  color: var(--accent-strong);
}

.shell {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(15, 118, 110, 0.12) 1px, transparent 1px),
    linear-gradient(0deg, rgba(15, 118, 110, 0.08) 1px, transparent 1px),
    linear-gradient(135deg, #ffffff 0%, #f4f8f6 100%);
  background-size: 48px 48px, 48px 48px, auto;
  padding: 72px 0 56px;
}

.eyebrow {
  margin: 0 0 18px;
  color: var(--accent-strong);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1 {
  max-width: 760px;
  margin: 0;
  font-size: clamp(2.6rem, 6vw, 5.8rem);
  line-height: 0.95;
  letter-spacing: 0;
}

.lead {
  max-width: 700px;
  margin: 24px 0 0;
  color: var(--muted);
  font-size: 1.18rem;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 30px;
}

.nav a {
  border-bottom: 2px solid var(--accent);
  color: var(--ink);
  font-weight: 700;
  text-decoration: none;
}

main {
  padding: 48px 0 72px;
}

.grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(280px, 0.9fr);
  gap: 42px;
}

section {
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}

h2 {
  margin: 0 0 14px;
  font-size: 1.55rem;
  line-height: 1.2;
  letter-spacing: 0;
}

h3 {
  margin: 26px 0 10px;
  font-size: 1rem;
  letter-spacing: 0;
}

p {
  margin: 0 0 14px;
}

ul,
ol {
  margin: 0;
  padding-left: 1.2rem;
}

li + li {
  margin-top: 6px;
}

code,
pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
}

pre {
  overflow-x: auto;
  padding: 18px;
  border: 1px solid var(--line);
  background: var(--panel);
}

.system-map {
  padding: 24px;
  border: 1px solid var(--line);
  background: var(--panel);
}

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

.node + .node {
  margin-top: 12px;
}

.arrow {
  margin: 10px 0;
  color: var(--accent-strong);
  font-weight: 700;
}

.meta {
  color: var(--muted);
  font-size: 0.94rem;
}

.footer {
  border-top: 1px solid var(--line);
  padding: 28px 0;
  color: var(--muted);
  font-size: 0.94rem;
}

@media (max-width: 820px) {
  .shell {
    width: min(100% - 28px, 1120px);
  }

  .hero {
    padding: 48px 0 40px;
  }

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