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

:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --text: #1e293b;
  --text-muted: #64748b;
  --bg: #f8fafc;
  --white: #ffffff;
  --border: #e2e8f0;
  --radius: 12px;
}

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 1rem 1.5rem;
  position: sticky;
  top: 0;
  z-index: 10;
}

.header-inner {
  max-width: 800px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--primary);
  text-decoration: none;
  letter-spacing: -0.02em;
}

.logo span { color: var(--text); }

nav { display: flex; gap: 0.5rem; flex-wrap: wrap; }

nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.4rem 0.75rem;
  border-radius: 8px;
  transition: background 0.15s, color 0.15s;
}

nav a:hover, nav a.active {
  background: #eef2ff;
  color: var(--primary);
}

main {
  flex: 1;
  max-width: 800px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 4rem;
  width: 100%;
}

.hero {
  text-align: center;
  padding: 3rem 0 2rem;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0.75rem;
}

.hero p {
  color: var(--text-muted);
  font-size: 1.05rem;
  max-width: 520px;
  margin: 0 auto 2rem;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
  margin-top: 1rem;
}

.card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  text-decoration: none;
  color: inherit;
  transition: box-shadow 0.2s, border-color 0.2s;
}

.card:hover {
  box-shadow: 0 4px 24px rgba(99, 102, 241, 0.12);
  border-color: var(--primary);
}

.card h2 {
  font-size: 1.15rem;
  margin-bottom: 0.5rem;
  color: var(--primary);
}

.card p { color: var(--text-muted); font-size: 0.925rem; }

.doc-header { margin-bottom: 2rem; }

.doc-header h1 {
  font-size: 1.85rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  margin-bottom: 0.5rem;
}

.doc-header .updated {
  color: var(--text-muted);
  font-size: 0.875rem;
}

section {
  margin-bottom: 2rem;
}

section h2 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  color: var(--text);
}

section p { margin-bottom: 0.75rem; }

section ul {
  padding-left: 1.5rem;
  margin-bottom: 0.75rem;
}

section li { margin-bottom: 0.35rem; }

section li strong { font-weight: 600; }

footer {
  background: var(--white);
  border-top: 1px solid var(--border);
  padding: 1.5rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.825rem;
}

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

footer a:hover { text-decoration: underline; }

.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.925rem;
  text-decoration: none;
  transition: background 0.15s, transform 0.1s;
  border: none;
  cursor: pointer;
}

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

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

.btn-danger {
  background: #dc2626;
  color: var(--white);
}

.btn-danger:hover {
  background: #b91c1c;
  transform: translateY(-1px);
}

.btn-outline {
  background: var(--white);
  color: var(--primary);
  border: 1px solid var(--primary);
}

.btn-outline:hover {
  background: #eef2ff;
}

.cta-box {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  margin: 2rem 0;
  text-align: center;
}

.cta-box h2 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.cta-box p {
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.cta-actions {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

.steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
  margin: 1rem 0;
}

.steps li {
  counter-increment: step;
  padding: 1rem 1rem 1rem 3rem;
  position: relative;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 0.75rem;
}

.steps li::before {
  content: counter(step);
  position: absolute;
  left: 1rem;
  top: 1rem;
  width: 1.5rem;
  height: 1.5rem;
  background: var(--primary);
  color: var(--white);
  border-radius: 50%;
  font-size: 0.8rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.alert {
  background: #fef2f2;
  border: 1px solid #fecaca;
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  color: #991b1b;
  font-size: 0.925rem;
  margin: 1.5rem 0;
}

@media (max-width: 600px) {
  .hero h1 { font-size: 1.5rem; }
  .doc-header h1 { font-size: 1.5rem; }
  .header-inner { flex-direction: column; align-items: flex-start; }
}