:root {
  --bg: #fafafa;
  --fg: #1a1a1a;
  --muted: #666;
  --accent: #c8102e;
  --border: #e5e5e5;
  --card: #fff;
}

* { box-sizing: border-box; }

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

header {
  background: var(--card);
  border-bottom: 1px solid var(--border);
  padding: 1rem 2rem;
}

header nav {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

header .brand {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--fg);
  text-decoration: none;
  letter-spacing: -0.02em;
}

header .brand span {
  color: var(--accent);
}

header .links a {
  color: var(--muted);
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 0.95rem;
}

header .links a:hover {
  color: var(--fg);
}

main {
  max-width: 760px;
  margin: 3rem auto;
  padding: 0 2rem;
}

main h1 {
  font-size: 2.25rem;
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
}

main h2 {
  font-size: 1.4rem;
  margin: 2.5rem 0 0.75rem;
  letter-spacing: -0.01em;
}

main h3 {
  font-size: 1.1rem;
  margin: 1.5rem 0 0.5rem;
}

main .lede {
  font-size: 1.15rem;
  color: var(--muted);
  margin: 0 0 2rem;
}

main ul {
  padding-left: 1.5rem;
}

main li {
  margin: 0.25rem 0;
}

main p {
  margin: 0.75rem 0;
}

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

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  margin: 1rem 0;
  display: block;
  text-decoration: none;
  color: var(--fg);
}

.card:hover {
  border-color: var(--accent);
}

.card h3 {
  margin-top: 0;
  color: var(--accent);
}

.card p {
  color: var(--muted);
  margin: 0.5rem 0 0;
}

.note {
  background: #fff8e1;
  border-left: 3px solid #f5a623;
  padding: 0.75rem 1rem;
  margin: 1.5rem 0;
  border-radius: 4px;
  font-size: 0.95rem;
}

footer {
  text-align: center;
  color: var(--muted);
  padding: 2rem;
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
  margin-top: 4rem;
}

footer a {
  color: var(--muted);
}