:root {
  --bg-dark: #0b0e14;
  --bg-light: #f5f7fa;
  --text-dark: #0e1116;
  --text-light: #ffffff;
  --muted: #6b7280;
  --accent: #2563eb;
  --border: #e5e7eb;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, sans-serif;
  color: var(--text-dark);
  line-height: 1.6;
  background: white;
}

.container {
  max-width: 1100px;
  margin: auto;
  padding: 0 24px;
}

.container.narrow {
  max-width: 760px;
}

.nav {
  border-bottom: 1px solid var(--border);
  background: white;
  position: sticky;
  top: 0;
  z-index: 10;
}

.nav-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}

.logo {
  font-weight: 600;
  letter-spacing: 0.5px;
}

nav a {
  margin-left: 20px;
  text-decoration: none;
  color: var(--text-dark);
  font-size: 14px;
}

.hero {
  background: var(--bg-dark);
  color: var(--text-light);
  padding: 96px 0;
  text-align: center;
}

.hero h1 {
  font-size: 42px;
  margin-bottom: 20px;
}

.hero-sub {
  font-size: 18px;
  max-width: 760px;
  margin: auto;
  color: #d1d5db;
}

.cta-group {
  margin-top: 32px;
}

.btn-primary,
.btn-secondary,
.btn-outline {
  display: inline-block;
  padding: 12px 20px;
  border-radius: 6px;
  text-decoration: none;
  font-weight: 500;
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-secondary {
  border: 1px solid white;
  color: white;
  margin-left: 12px;
}

.btn-outline {
  border: 1px solid var(--border);
  padding: 8px 14px;
}

.trust-strip {
  margin-top: 48px;
  display: flex;
  justify-content: center;
  gap: 24px;
  font-size: 14px;
  color: #9ca3af;
}

.section {
  padding: 80px 0;
}

.section.light {
  background: var(--bg-light);
}

.section h2 {
  font-size: 32px;
  margin-bottom: 16px;
}

.section-intro {
  max-width: 700px;
  margin-bottom: 48px;
  color: var(--muted);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 24px;
}

.card {
  border: 1px solid var(--border);
  padding: 24px;
  border-radius: 8px;
  background: white;
}

.steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 24px;
}

.step span {
  font-size: 24px;
  font-weight: bold;
  color: var(--accent);
}

.use-list,
.arch-list {
  margin-top: 24px;
  list-style: disc;
  padding-left: 20px;
}

.footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
  font-size: 14px;
  color: var(--muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
}

.footer a {
  color: var(--muted);
  text-decoration: none;
}