body{font-family:Arial,sans-serif;max-width:900px;margin:40px auto;padding:20px;background:#f7f7f7}
.card{background:white;border-radius:12px;padding:20px;margin:20px 0;box-shadow:0 2px 8px rgba(0,0,0,.08)}
.big{font-size:48px;font-weight:bold}
button,input{padding:8px 12px;font-size:16px}