:root {
  --bg: #fbf7f2;
  --card: #ffffff;
  --text: #3b2a1e;
  --muted: #8a7b6e;
  --border: #e6dcd0;
  --primary: #d0704a;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1f1915;
    --card: #2a221d;
    --text: #f3ebe3;
    --muted: #b5a698;
    --border: #3d332c;
    --primary: #e89a78;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Noto Sans JP", sans-serif;
  line-height: 1.8;
}
main { max-width: 720px; margin: 0 auto; padding: 32px 16px 64px; }
header { display: flex; align-items: center; gap: 12px; margin-bottom: 24px; }
header img { width: 56px; height: 56px; border-radius: 14px; }
header a { color: inherit; text-decoration: none; font-size: 22px; font-weight: 800; }
h1 { font-size: 26px; line-height: 1.4; }
h2 { font-size: 19px; margin-top: 36px; border-bottom: 1px solid var(--border); padding-bottom: 4px; }
h3 { font-size: 16px; margin-top: 24px; }
a { color: var(--primary); }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 16px; padding: 20px; margin: 16px 0; }
.muted { color: var(--muted); font-size: 14px; }
nav { display: flex; gap: 16px; flex-wrap: wrap; margin-top: 40px; font-size: 14px; }
footer { margin-top: 48px; color: var(--muted); font-size: 13px; }