:root{color-scheme:light;font-family:Segoe UI,Noto Sans JP,sans-serif;line-height:1.5}*{box-sizing:border-box}body{margin:0;background:#f4f7fb;color:#0f172a}.container{max-width:760px;margin:8vh auto;padding:2rem;background:#fff;border:1px solid #dbe3ef;border-radius:12px}h1{margin-top:0}code,a{margin-left:.5rem}