:root{--background:#fff;--foreground:#171717;--border:#e5e5e5;--accent:#0b5cad}@media (prefers-color-scheme:dark){:root{--background:#0a0a0a;--foreground:#ededed;--border:#2a2a2a;--accent:#5aa9e6}}*{box-sizing:border-box;margin:0;padding:0}body{color:var(--foreground);background:var(--background);font-family:system-ui,-apple-system,Segoe UI,Hiragino Sans,Noto Sans JP,sans-serif;line-height:1.7}main{max-width:720px;margin:0 auto;padding:3rem 1.5rem}a{color:var(--accent)}.card{border:1px solid var(--border);border-radius:8px;margin-top:1.5rem;padding:1.25rem 1.5rem}.button{background:var(--accent);color:#fff;cursor:pointer;border:none;border-radius:6px;padding:.6rem 1.4rem;font-size:1rem;text-decoration:none;display:inline-block}pre{background:#7f7f7f1a;border-radius:6px;margin-top:.75rem;padding:1rem;font-size:.85rem;overflow-x:auto}