:root{--bg:#fbfaf7;--fg:#1d2433;--muted:#5b6475;--accent:#0b6b5c;--line:#e3e0d8;--card:#fff}
@media (prefers-color-scheme:dark){:root{--bg:#14171f;--fg:#e8eaf0;--muted:#a0a8b8;--accent:#4fd1b5;--line:#2a2f3b;--card:#1b1f29}}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--fg);font:17px/1.65 Georgia,'Iowan Old Style',serif}
header,footer,main{max-width:760px;margin:0 auto;padding:0 16px}
header{display:flex;justify-content:space-between;align-items:center;padding-top:20px;padding-bottom:12px;border-bottom:1px solid var(--line);flex-wrap:wrap;gap:8px}
header a.brand{font-weight:700;font-size:1.25rem;text-decoration:none;color:var(--fg)}
nav a{margin-left:16px;font:600 .9rem system-ui,sans-serif;color:var(--muted);text-decoration:none}
a{color:var(--accent)}h1{font-size:2rem;line-height:1.2;margin:1.2rem 0 .5rem}h2{margin-top:2rem}
table{width:100%;border-collapse:collapse;margin:1rem 0;font:.9rem system-ui,sans-serif;display:block;overflow-x:auto}
th,td{border:1px solid var(--line);padding:6px 10px;text-align:left}th{background:var(--card)}
blockquote{margin:1rem 0;padding:.5rem 1rem;border-left:4px solid var(--accent);background:var(--card);color:var(--muted)}
.meta{color:var(--muted);font:.85rem system-ui,sans-serif}.disclosure{font:.85rem system-ui,sans-serif;background:var(--card);border:1px solid var(--line);padding:8px 12px;border-radius:6px;margin:1rem 0}
.card{border:1px solid var(--line);background:var(--card);border-radius:8px;padding:12px 16px;margin:12px 0}.card h3{margin:.2rem 0}
.calc label{display:block;margin:.8rem 0 .2rem;font:600 .9rem system-ui,sans-serif}.calc input{width:100%;padding:8px;font-size:1rem;border:1px solid var(--line);border-radius:6px;background:var(--card);color:var(--fg)}
.result{margin-top:1rem;padding:12px 16px;border-radius:8px;background:var(--card);border:1px solid var(--accent);font:1rem system-ui,sans-serif}
footer{border-top:1px solid var(--line);margin-top:3rem;padding-top:1rem;padding-bottom:2rem;color:var(--muted);font:.85rem system-ui,sans-serif}
input[type=checkbox]{margin-right:6px}