:root {
  --bg: #ffffff;
  --fg: #1f2933;
  --muted: #5f6c7b;
  --accent: #2563eb;
  --border: #e4e7eb;
  --surface: #f7f8fa;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1419;
    --fg: #e6e9ee;
    --muted: #9aa5b1;
    --accent: #6ea8fe;
    --border: #232b35;
    --surface: #161c24;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.65;
}

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

header,
main,
footer {
  max-width: 760px;
  margin: 0 auto;
  padding: 0 20px;
}

header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.brand {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--fg);
  text-decoration: none;
}

nav a {
  margin-left: 16px;
  text-decoration: none;
  font-size: 0.95rem;
}

nav a:hover {
  text-decoration: underline;
}

main {
  padding-top: 32px;
  padding-bottom: 48px;
}

h1 {
  font-size: 1.9rem;
  line-height: 1.2;
  margin: 0 0 4px;
}

h2 {
  font-size: 1.2rem;
  margin: 36px 0 8px;
}

.updated {
  color: var(--muted);
  font-size: 0.9rem;
  margin: 0 0 24px;
}

ul {
  padding-left: 22px;
}

li {
  margin: 4px 0;
}

.cards {
  display: grid;
  gap: 16px;
  margin-top: 24px;
}

.card {
  display: block;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  color: var(--fg);
  text-decoration: none;
}

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

.card strong {
  display: block;
  margin-bottom: 4px;
}

.card span {
  color: var(--muted);
  font-size: 0.95rem;
}

footer {
  padding-top: 20px;
  padding-bottom: 32px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.875rem;
}