:root {
  --bg: #f7f7fb;
  --card: #ffffff;
  --text: #1a1a1a;
  --text-secondary: #4a4a55;
  --text-muted: #8a8a96;
  --accent: #7c3aed;
  --accent-light: #a855f7;
  --border: #e7e7ee;
  --radius: 16px;
  --maxw: 760px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

/* ── Header ─────────────────────────────────────────────── */
.site-header {
  background: linear-gradient(135deg, #0d0d0d 0%, #1f1235 100%);
  color: #fff;
  padding: 56px 24px 48px;
  text-align: center;
}

.site-header .brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-size: 22px;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #fff;
  text-decoration: none;
}

.site-header .brand .logo {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-light));
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
}

.site-header .tagline {
  margin: 16px auto 0;
  max-width: 520px;
  color: rgba(255, 255, 255, 0.7);
  font-size: 15px;
}

/* ── Layout ─────────────────────────────────────────────── */
.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
}

main {
  padding: 48px 0 64px;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 36px;
  box-shadow: 0 1px 3px rgba(16, 16, 32, 0.04);
}

/* ── Typography ─────────────────────────────────────────── */
h1 {
  font-size: 30px;
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin: 0 0 4px;
}

h2 {
  font-size: 19px;
  margin: 36px 0 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

p,
li {
  font-size: 15.5px;
  color: var(--text-secondary);
}

ul {
  padding-left: 20px;
}

li {
  margin-bottom: 6px;
}

strong {
  color: var(--text);
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.date {
  color: var(--text-muted);
  font-size: 14px;
  margin: 0 0 28px;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 24px;
}

/* ── Landing cards ──────────────────────────────────────── */
.doc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 8px;
}

.doc-card {
  display: block;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px 24px;
  text-decoration: none;
  color: var(--text);
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
}

.doc-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(124, 58, 237, 0.12);
  border-color: var(--accent-light);
  text-decoration: none;
}

.doc-card .doc-icon {
  font-size: 26px;
  margin-bottom: 12px;
}

.doc-card h3 {
  margin: 0 0 6px;
  font-size: 17px;
}

.doc-card p {
  margin: 0;
  font-size: 14px;
  color: var(--text-muted);
}

/* ── Footer ─────────────────────────────────────────────── */
.site-footer {
  text-align: center;
  padding: 32px 24px 48px;
  color: var(--text-muted);
  font-size: 13px;
}

.site-footer a {
  color: var(--text-muted);
  text-decoration: underline;
}

@media (max-width: 560px) {
  .doc-grid {
    grid-template-columns: 1fr;
  }
  .card {
    padding: 28px 22px;
  }
  .site-header {
    padding: 44px 20px 36px;
  }
}