:root {
  color-scheme: light;
  --bg: #f7f7f9;
  --card: #fff;
  --text: #1a1a1e;
  --muted: #5c5c66;
  --accent: #2563eb;
  --border: #e4e4ea;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP",
    system-ui, sans-serif;
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
}

.wrap {
  max-width: 40rem;
  margin: 0 auto;
  padding: 2rem 1.25rem 3rem;
}

header {
  margin-bottom: 2rem;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
}

.sub {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.25rem 1.35rem;
  margin-bottom: 1rem;
}

.card h2 {
  font-size: 1rem;
  margin: 0 0 0.75rem;
}

p {
  margin: 0 0 0.75rem;
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 2px;
}

a:hover {
  text-decoration-thickness: 2px;
}

ul {
  margin: 0.5rem 0 0;
  padding-left: 1.2rem;
}

footer {
  margin-top: 2rem;
  font-size: 0.85rem;
  color: var(--muted);
}

.nav {
  margin-top: 1rem;
  font-size: 0.95rem;
}