body{font-family:Arial,sans-serif;margin:0;background:#0f172a;color:#fff}header{display:flex;justify-content:space-between;padding:20px;background:#111827;position:sticky;top:0}nav a{color:#fff;margin:0 10px;text-decoration:none}.hero{padding:70px 20px;text-align:center;background:linear-gradient(135deg,#2563eb,#0ea5e9)}.btn{background:#fff;color:#111;padding:12px 18px;border-radius:8px;text-decoration:none}.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:16px;padding:10px}section{padding:30px 20px}#chat{height:180px;background:#fff;color:#000;padding:10px;overflow:auto;border-radius:8px;margin-bottom:8px}input,textarea,button{display:block;width:100%;max-width:500px;margin:8px 0;padding:10px}