:root{--bg:#fafaf8;--fg:#1d1d1b;--muted:#6b6b66;--line:#e3e2dd;--accent:#2f5d8a}
@media (prefers-color-scheme:dark){:root{--bg:#161615;--fg:#ecebe6;--muted:#9c9b95;--line:#2c2c2a;--accent:#8fb4dc}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.8 system-ui,-apple-system,"Hiragino Sans","Noto Sans JP",sans-serif}
main{max-width:720px;margin:0 auto;padding:48px 16px 64px}
h1{font-size:1.6rem;line-height:1.4;margin:0 0 4px}
h2{font-size:1.1rem;margin:40px 0 8px;padding-top:16px;border-top:1px solid var(--line)}
p,li{margin:0 0 10px}
.sub{color:var(--muted);margin-bottom:32px}
a{color:var(--accent)}
nav{display:flex;gap:16px;font-size:.9rem;margin-bottom:40px}
footer{margin-top:56px;color:var(--muted);font-size:.85rem}
.en{color:var(--muted)}