:root {
  --bg: #f7f4ee;
  --paper: #ffffff;
  --ink: #1f2933;
  --muted: #5f6b7a;
  --line: #d9d3c7;
  --accent: #4b5563;
  --warning: #7c2d12;
}

* { box-sizing: border-box; }

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

.site-shell {
  max-width: 980px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

.lab-banner {
  border: 1px solid var(--line);
  background: #fff8e6;
  color: var(--warning);
  border-radius: 14px;
  padding: 14px 16px;
  margin-bottom: 28px;
  font-size: 0.95rem;
}

.lab-banner.sandbox {
  background: #fff1f2;
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 32px;
}

.nav a {
  color: var(--accent);
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--paper);
  padding: 8px 12px;
  border-radius: 999px;
}

.hero {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 24px;
  padding: 32px;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 4rem);
  line-height: 1;
  margin: 0 0 16px;
  letter-spacing: -0.05em;
}

.kicker {
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.8rem;
  margin-bottom: 12px;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 20px;
}

.flow {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px;
  margin: 24px 0;
}

.flow-step {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 18px;
}

.flow-step span {
  display: inline-flex;
  width: 28px;
  height: 28px;
  border-radius: 999px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--line);
  margin-bottom: 10px;
  color: var(--muted);
}

.sample {
  white-space: pre-wrap;
  background: #111827;
  color: #f9fafb;
  border-radius: 16px;
  padding: 18px;
  overflow-x: auto;
}

.footer-note {
  margin-top: 40px;
  color: var(--muted);
  font-size: 0.9rem;
}