:root {
  --fg: #1f2933;
  --muted: #52606d;
  --bg: #fafbfc;
  --accent: #2563eb;
  --border: #e4e7eb;
}

* {
  box-sizing: border-box;
}

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

.navbar {
  display: flex;
  gap: 1rem;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: #fff;
}

.navbar a {
  color: var(--muted);
  text-decoration: none;
  font-weight: 500;
}

.navbar a.active,
.navbar a:hover {
  color: var(--accent);
}

.container {
  max-width: 720px;
  margin: 2rem auto;
  padding: 0 1.5rem;
}

h1 {
  margin-top: 0;
}

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

code {
  background: #eef2f6;
  padding: 0.1em 0.35em;
  border-radius: 4px;
  font-size: 0.9em;
}