:root {
  color-scheme: light dark;
  --bg: #101418;
  --card: #161b22;
  --fg: #f5f7fa;
  --muted: #9aa4b2;
  --accent: #3d9a8b;
  --accent-deep: #175e52;
  --border: #2d333b;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #fafafa;
    --card: #ffffff;
    --fg: #0f172a;
    --muted: #5c6b7a;
    --border: #e2e8f0;
  }
}

* { box-sizing: border-box; }

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

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

header, main, footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.25rem;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--fg);
  font-weight: 700;
  font-size: 1.1rem;
}

.logo img { width: 40px; height: 40px; border-radius: 10px; }

.cta {
  display: inline-block;
  background: var(--accent-deep);
  color: #fff;
  text-decoration: none;
  padding: 0.65rem 1.1rem;
  border-radius: 10px;
  font-weight: 600;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.25rem 1.35rem;
  margin: 1rem 0;
}

h1 {
  font-size: clamp(1.6rem, 4vw, 2rem);
  line-height: 1.2;
  margin: 0.5rem 0 1rem;
}

h2 { font-size: 1.1rem; margin: 1.25rem 0 0.5rem; }

p, li { color: var(--muted); }

ul { padding-left: 1.2rem; }

footer {
  font-size: 0.85rem;
  color: var(--muted);
  border-top: 1px solid var(--border);
  margin-top: 2rem;
}