:root {
  --bg: #0d1117;
  --fg: #e6edf3;
  --accent: #3b82f6;
  --muted: #9ca3af;
  --card-bg: #161b22;
  --border: #1f2937;
  --mono: ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

body {
  font-family: var(--sans);
  color: var(--fg);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* --- HERO SECTION --- */
.hero {
  text-align: center;
  padding: 6rem 1rem 4rem;
  background: radial-gradient(circle at top, rgba(59,130,246,0.15), transparent 70%);
}

.hero small {
  letter-spacing: 0.2em;
  color: var(--muted);
  font-size: 0.9rem;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 700;
  color: var(--fg);
  margin: 0.75rem 0;
}

.hero p {
  color: var(--muted);
  font-size: 1.1rem;
  margin-bottom: 1.5rem;
}

.hero .buttons {
  display: flex;
  justify-content: center;
  gap: 1rem;
}

.hero a {
  background: var(--accent);
  color: white;
  padding: 0.6rem 1.25rem;
  border-radius: 9999px;
  font-weight: 500;
  text-decoration: none;
  transition: opacity 0.2s;
}

.hero a:hover {
  opacity: 0.85;
}

/* --- SECTIONS --- */
section {
  max-width: 72rem;
  margin: 0 auto;
  padding: 2rem 1.5rem;
}

section h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 1.5rem;
  color: var(--fg);
}

/* --- FEATURE GRID --- */
.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.5rem;
  transition: border-color 0.2s, transform 0.1s;
}

.card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.card h3 {
  font-size: 1.1rem;
  margin-bottom: 0.5rem;
  color: var(--fg);
}

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

/* --- CODE + PRE --- */
pre {
  background: var(--card-bg);
  color: #c9d1d9;
  padding: 1rem;
  border-radius: 10px;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.9rem;
  margin-top: 1rem;
}

/* --- FOOTER --- */
footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
  padding: 3rem 1rem;
  border-top: 1px solid var(--border);
  margin-top: 4rem;
}