:root {
  --bg: #0f1117;
  --card-bg: #1a1e29;
  --border: #2a3040;
  --text: #e2e8f0;
  --text-muted: #94a3b8;
  --accent: #38bdf8;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

header {
  border-bottom: 1px solid var(--border);
  padding: 1.2rem 2rem;
}

.nav-container {
  max-width: 1000px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text);
  text-decoration: none;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 1.5rem;
}

.nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.2s;
}

.nav-links a:hover, .nav-links a.active {
  color: var(--accent);
}

.container {
  max-width: 1000px;
  margin: 3rem auto;
  padding: 0 1.5rem;
  flex: 1;
}

.hero {
  text-align: center;
  margin-bottom: 3.5rem;
}

.hero h1 {
  font-size: 2.5rem;
  letter-spacing: -0.02em;
  margin-bottom: 0.8rem;
}

.subtitle {
  color: var(--text-muted);
  font-size: 1.2rem;
}

.grid-section {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  padding: 2rem;
  border-radius: 10px;
}

.card h3 {
  margin-bottom: 0.8rem;
  color: var(--accent);
}

.content h2 {
  font-size: 2rem;
  margin-bottom: 1.2rem;
}

.content p {
  margin-bottom: 1rem;
  color: var(--text-muted);
}

footer {
  text-align: center;
  padding: 2rem;
  border-top: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.85rem;
}