:root{--bg:#f8fafc;--fg:#111827;--card:#fff}.dark{--bg:#0f172a;--fg:#f8fafc;--card:#1e293b}body{margin:0;font-family:Arial,sans-serif;background:var(--bg);color:var(--fg);transition:.3s}nav{display:flex;justify-content:space-between;padding:1rem 2rem;position:sticky;top:0;background:var(--card)}.hero{text-align:center;padding:5rem 1rem}.card,.chips span{background:var(--card);padding:1rem;border-radius:10px;display:inline-block;margin:.5rem}@media(max-width:768px){nav{padding:1rem}}