:root {
  --bg: #0f172a;
  --bg-elevated: #111827;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --radius: 0.75rem;
  --code-bg: #1f2937;
}

/* reset / override */
html, body {
  height: 100%;
}

body {
  margin: 0 auto !important;     /* center the whole page */
  max-width: 900px;              /* column width */
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.6;
  display: block !important;     /* kill any flex coming from elsewhere */
  padding: 0 1rem;               /* small side padding on mobile */
}

header {
  padding: 2.5rem 0 1.5rem;
}

h1 {
  font-size: 2.3rem;
  margin-bottom: 0.25rem;
}

h2 {
  margin-top: 2rem;
  border-bottom: 1px solid rgba(148, 163, 184, 0.2);
  padding-bottom: 0.25rem;
}

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

em {
  color: var(--accent);
  font-style: normal;
}

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

figure {
  background: var(--bg-elevated);
  padding: 1rem;
  border-radius: var(--radius);
  margin: 1.5rem 0;
  text-align: center;
}

figure img {
  max-width: 100%;
  height: auto