:root {
  --bg: #0a0a0f;
  --surface: #14141f;
  --border: #2a2a3a;
  --text: #e0e0e8;
  --text-muted: #8888a0;
  --accent: #6c5ce7;
  --accent-hover: #7d6ff0;
  --success: #00b894;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--border);
  position: sticky;
  top: 0;
  background: var(--bg);
  z-index: 10;
}

.logo { font-size: 1.5rem; font-weight: 700; color: var(--accent); }
.nav-links { display: flex; gap: 1.5rem; align-items: center; }
.nav-links a { color: var(--text-muted); text-decoration: none; }
.nav-links a:hover { color: var(--text); }

.btn {
  padding: 0.5rem 1.25rem;
  border-radius: 8px;
  text-decoration: none;
  font-weight: 600;
  border: none;
  cursor: pointer;
  display: inline-block;
}
.btn-primary { background: var(--accent); color: white; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-secondary { background: transparent; border: 1px solid var(--border); color: var(--text); }
.btn-lg { padding: 0.75rem 2rem; font-size: 1.1rem; }

.hero {
  text-align: center;
  padding: 6rem 2rem;
  max-width: 800px;
  margin: 0 auto;
}
.hero h1 { font-size: 3.5rem; margin-bottom: 1rem; }
.hero p { font-size: 1.25rem; color: var(--text-muted); margin-bottom: 2rem; }
.hero-cta { display: flex; gap: 1rem; justify-content: center; }

.section {
  max-width: 1000px;
  margin: 0 auto;
  padding: 4rem 2rem;
}
.section h2 { font-size: 2rem; margin-bottom: 1.5rem; }

.model-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}
.model-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
}
.model-card h3 { margin-bottom: 0.5rem; }
.model-desc { color: var(--text-muted); margin-bottom: 1rem; }
.model-pricing { display: flex; flex-direction: column; gap: 0.25rem; font-size: 0.9rem; color: var(--success); }

.pricing-table { display: flex; flex-direction: column; gap: 0.5rem; }
.pricing-row {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  padding: 0.75rem 1rem;
  border-radius: 8px;
}
.pricing-row.header { font-weight: 700; border-bottom: 1px solid var(--border); }
.pricing-row:not(.header) { background: var(--surface); }

.code-block {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  overflow-x: auto;
}
.code-block pre { font-family: "SF Mono", Monaco, monospace; font-size: 0.9rem; }

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

/* Mobile responsive */
@media (max-width: 768px) {
  nav {
    flex-direction: column;
    gap: 0.75rem;
    padding: 1rem;
  }
  .nav-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
  }
  .hero {
    padding: 3rem 1.25rem;
  }
  .hero h1 {
    font-size: 2.2rem;
  }
  .hero p {
    font-size: 1rem;
  }
  .hero-cta {
    flex-direction: column;
    align-items: center;
  }
  .hero-cta .btn {
    width: 100%;
    max-width: 280px;
    text-align: center;
  }
  .section {
    padding: 2.5rem 1.25rem;
  }
  .section h2 {
    font-size: 1.6rem;
  }
  .model-grid {
    grid-template-columns: 1fr;
  }
  .pricing-row {
    grid-template-columns: 1fr 1fr;
    gap: 0.25rem;
    font-size: 0.85rem;
  }
  .pricing-row span:nth-child(3),
  .pricing-row span:nth-child(4) {
    display: none;
  }
  .code-block {
    padding: 1rem;
  }
  .code-block pre {
    font-size: 0.75rem;
  }
  .stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .api-key-box {
    flex-direction: column;
    gap: 0.5rem;
    align-items: flex-start;
  }
  .api-key-box code {
    font-size: 0.75rem;
    word-break: break-all;
  }
}