:root {
  --bg: #f5f7fa;
  --surface: #ffffff;
  --text: #1f2933;
  --text-muted: #52606d;
  --primary: #1a73e8;
  --primary-dark: #1558b0;
  --border: #e4e7eb;
  --radius: 14px;
  --shadow: 0 10px 30px rgba(0, 0, 0, 0.06);
}

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

html {
  scroll-behavior: smooth;
}

body {
  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;
}

.container {
  width: 100%;
  max-width: 820px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, #1a73e8 0%, #6a3de8 100%);
  color: #fff;
  padding: 64px 0 48px;
  text-align: center;
}

.badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.18);
  border: 1px solid rgba(255, 255, 255, 0.3);
  padding: 6px 16px;
  border-radius: 999px;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 18px;
}

.hero h1 {
  font-size: 2.6rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.subtitle {
  margin: 14px auto 0;
  max-width: 560px;
  font-size: 1.1rem;
  opacity: 0.92;
}

.updated {
  margin-top: 18px;
  font-size: 0.85rem;
  opacity: 0.8;
}

/* Nav */
.nav {
  margin-top: 26px;
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

.nav a {
  display: inline-block;
  padding: 8px 18px;
  border-radius: 999px;
  font-size: 0.92rem;
  font-weight: 600;
  color: #fff;
  text-decoration: none;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.3);
  transition: background 0.15s ease;
}

.nav a:hover {
  background: rgba(255, 255, 255, 0.28);
}

.nav a.active {
  background: #fff;
  color: var(--primary);
  border-color: #fff;
}

/* Content */
.content {
  background: var(--surface);
  margin: -28px auto 40px;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 44px;
  position: relative;
}

.content section {
  padding: 22px 0;
  border-bottom: 1px solid var(--border);
}

.content section:last-child {
  border-bottom: none;
}

.content h2 {
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text);
}

.content h3 {
  font-size: 1.05rem;
  font-weight: 600;
  margin: 18px 0 8px;
  color: var(--text);
}

.content p {
  color: var(--text-muted);
  margin-bottom: 10px;
}

.content ul {
  margin: 8px 0 8px 22px;
  color: var(--text-muted);
}

.content li {
  margin-bottom: 8px;
}

.content a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

.content a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

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

/* Footer */
.footer {
  text-align: center;
  padding: 32px 0 48px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.footer .disclaimer {
  margin-top: 8px;
  font-size: 0.8rem;
  opacity: 0.85;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

/* Responsive */
@media (max-width: 600px) {
  .hero {
    padding: 48px 0 40px;
  }

  .hero h1 {
    font-size: 2rem;
  }

  .subtitle {
    font-size: 1rem;
  }

  .content {
    padding: 28px 22px;
  }

  .content h2 {
    font-size: 1.25rem;
  }
}