:root {
  --bg: #f4f7f8;
  --card: #ffffff;
  --text: #0d1722;
  --muted: #4d5d70;
  --blue: #177ead;
  --line: #dce8eb;
}
body {
  margin: 0;
  background:
    linear-gradient(rgba(23, 126, 173, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 126, 173, 0.06) 1px, transparent 1px),
    var(--bg);
  background-size: 28px 28px;
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN",
    "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.75;
  padding: 28px;
}
.wrap {
  max-width: 860px;
  margin: 0 auto;
  background: var(--card);
  padding: clamp(24px, 5vw, 56px);
  border-radius: 8px;
  box-shadow: 0 10px 30px rgba(11, 28, 52, 0.08);
}
h1 { margin: 0; line-height: 1.25; }
h2 { margin-top: 2.2em; padding-top: 1.2em; border-top: 1px solid var(--line); }
h3 { margin-top: 1.4em; }
.lead { color: var(--muted); font-weight: 700; }
.meta { color: var(--muted); font-size: 0.95rem; margin-bottom: 20px; }
ul { padding-left: 1.2rem; }
li { margin: 0.4rem 0; }
a { color: var(--blue); font-weight: 800; }
.nav { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 28px; padding-top: 20px; border-top: 1px solid var(--line); }