:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --accent: #38bdf8;
  --accent-hover: #0ea5e9;
  --border: #334155;
}

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

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

header {
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-main);
  text-decoration: none;
  letter-spacing: -0.025em;
}

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

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

nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.95rem;
  transition: color 0.2s;
}

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

main {
  flex: 1;
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  padding: 4rem 2rem;
}

.hero {
  text-align: left;
  max-width: 800px;
  margin-bottom: 4rem;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 1rem;
  letter-spacing: -0.025em;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
}

.btn {
  display: inline-block;
  background-color: var(--accent);
  color: var(--bg-primary);
  padding: 0.75rem 1.5rem;
  border-radius: 0.375rem;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.2s;
}

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

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.card {
  background-color: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 0.5rem;
  padding: 2rem;
}

.card h3 {
  margin-bottom: 1rem;
  font-size: 1.25rem;
}

.card p {
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  font-size: 0.875rem;
}

@media (max-width: 768px) {
  .nav-container {
    flex-direction: column;
    gap: 1rem;
  }
  nav ul {
    flex-wrap: wrap;
    justify-content: center;
  }
  .hero h1 {
    font-size: 2.25rem;
  }
}