:root { color-scheme: light dark; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.7;
  color: #111827;
  background: #f7f7fa;
  padding: 24px 16px 48px;
}
.wrap { max-width: 720px; margin: 0 auto; }
h1 { font-size: 1.75rem; margin-bottom: 0.25rem; }
.meta { color: #6b7280; font-size: 0.9rem; margin-bottom: 1.5rem; }
h2 { font-size: 1.1rem; margin-top: 1.5rem; }
a { color: #7c3aed; }
footer { margin-top: 2rem; font-size: 0.85rem; color: #6b7280; }