:root {
  --bg: #0f172a;
  --fg: #e2e8f0;
  --accent: #38bdf8;
  --card: #1e293b;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
}

header {
  padding: 3rem 1.5rem 2rem;
  text-align: center;
  background: linear-gradient(180deg, #111c33, var(--bg));
}

header h1 {
  margin: 0;
  font-size: 2.75rem;
  color: var(--accent);
}

.tagline {
  font-size: 1.15rem;
  color: #94a3b8;
}

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 1rem 1.5rem 3rem;
}

section {
  background: var(--card);
  border-radius: 10px;
  padding: 1.5rem 1.75rem;
  margin-bottom: 1.5rem;
  box-shadow: 0 1px 3px rgba(0,0,0,.4);
}

h2 {
  margin-top: 0;
  color: var(--accent);
}

code {
  background: #0b1222;
  padding: .1rem .35rem;
  border-radius: 4px;
  color: #7dd3fc;
}

pre {
  background: #0b1222;
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  color: #7dd3fc;
}

a { color: var(--accent); }

footer {
  text-align: center;
  color: #64748b;
  padding: 1.5rem;
  font-size: .9rem;
}