:root {
  --bg: #0f172a;
  --card: #111827;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --accent: #38bdf8;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

header {
  padding: 48px 16px 24px;
  text-align: center;
}

nav {
  display: flex;
  justify-content: center;
  gap: 16px;
  padding: 12px 16px 32px;
  flex-wrap: wrap;
}

nav a {
  color: var(--text);
  text-decoration: none;
  padding: 8px 14px;
  border: 1px solid var(--accent);
  border-radius: 999px;
  transition: all 0.2s ease;
}

nav a:hover {
  background: var(--accent);
  color: #0b1120;
}

main {
  max-width: 920px;
  margin: 0 auto;
  padding: 0 16px 64px;
  display: grid;
  gap: 24px;
}

.card {
  background: var(--card);
  padding: 24px;
  border-radius: 16px;
  box-shadow: 0 12px 24px rgba(15, 23, 42, 0.2);
}

.muted {
  color: var(--muted);
}

footer {
  text-align: center;
  padding: 32px 16px 48px;
  color: var(--muted);
}

@media (max-width: 600px) {
  header {
    padding-top: 32px;
  }
}