:root {
  --ink: #0b0b0b;
  --paper: #faf9f7;
  --muted: #6c6c6c;
  --line: #d8d6d2;
  --accent: #8b8b8b;
  --accent-2: #b8b1a5;
  --max: 1100px;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "IBM Plex Sans", "Helvetica Neue", Arial, sans-serif;
  line-height: 1.5;
  letter-spacing: 0.1px;
}

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

a:hover {
  text-decoration: underline;
}

.container {
  max-width: var(--max);
  margin: 0 auto;
  padding: 28px 20px 80px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 18px;
  margin-bottom: 28px;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  font-family: "Space Grotesk", "IBM Plex Sans", sans-serif;
  letter-spacing: 0.6px;
}

.brand .mark {
  font-size: 20px;
  font-weight: 600;
}

.brand .tag {
  font-size: 12px;
  color: var(--muted);
}

.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 14px;
}

.nav a {
  color: var(--muted);
}

.nav a.active {
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 4px;
}

.hero {
  display: grid;
  gap: 28px;
  grid-template-columns: 1.2fr 0.8fr;
  align-items: start;
  margin: 36px 0 48px;
}

.hero h1 {
  font-family: "Space Grotesk", "IBM Plex Sans", sans-serif;
  font-size: clamp(28px, 4vw, 46px);
  line-height: 1.1;
  margin: 0 0 16px;
}

.hero p {
  font-size: 18px;
  color: var(--muted);
  margin: 0 0 24px;
}

.cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 1px solid var(--ink);
  padding: 10px 16px;
  font-size: 14px;
  background: var(--ink);
  color: var(--paper);
  text-decoration: none;
}

.btn.secondary {
  background: transparent;
  color: var(--ink);
}

.panel {
  border: 1px solid var(--line);
  padding: 18px;
  background: #fff;
}

.diagram {
  display: grid;
  gap: 12px;
}

.diagram .row {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 8px;
}

.diagram .box {
  border: 1px dashed var(--accent);
  padding: 10px;
  font-size: 12px;
  text-align: center;
  color: var(--muted);
}

.section {
  margin: 36px 0;
  display: grid;
  gap: 18px;
}

.section h2 {
  font-family: "Space Grotesk", "IBM Plex Sans", sans-serif;
  font-size: 22px;
  margin: 0;
}

.section p {
  margin: 0;
  color: var(--muted);
}

.grid-2 {
  display: grid;
  gap: 18px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.list {
  display: grid;
  gap: 10px;
}

.card {
  border: 1px solid var(--line);
  padding: 16px;
  background: #fff;
}

.card h3 {
  margin: 0 0 6px;
  font-size: 16px;
}

.card p {
  margin: 0;
  color: var(--muted);
}

.footer {
  border-top: 1px solid var(--line);
  margin-top: 48px;
  padding-top: 18px;
  font-size: 12px;
  color: var(--muted);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

.page-title {
  font-family: "Space Grotesk", "IBM Plex Sans", sans-serif;
  font-size: 30px;
  margin: 16px 0 8px;
}

.kicker {
  text-transform: uppercase;
  letter-spacing: 2px;
  font-size: 11px;
  color: var(--accent);
}

.note {
  border-left: 3px solid var(--ink);
  padding-left: 12px;
  color: var(--muted);
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: 1fr;
  }

  .grid-2 {
    grid-template-columns: 1fr;
  }

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