*{box-sizing:border-box}
body{font-family:Segoe UI, Roboto, Arial, sans-serif;margin:0;min-height:100vh;display:flex;align-items:center;justify-content:center;background:#f4f6f8}
main{background:#fff;padding:24px;border-radius:8px;box-shadow:0 6px 20px rgba(0,0,0,0.08);width:360px}
h1{margin:0 0 16px 0;text-align:center}
form{display:flex;flex-direction:column;gap:10px}
label{font-weight:600}
input[type=text],select{padding:10px;border:1px solid #d0d7de;border-radius:6px;font-size:1rem}
button{padding:10px;border:none;border-radius:6px;background:#0b76ef;color:#fff;font-weight:700;cursor:pointer}
button:hover{background:#0960c9}
#resultado{margin-top:16px;text-align:center;padding:12px;border-radius:6px;min-height:36px;font-size:1.25rem}
#resultado.ok{background:#e8f5e8;color:#2e7d32;border:2px solid #4caf50}
#resultado.err{background:#ffebee;color:#b71c1c;border:2px solid #f44336}