.redsys-box {
    max-width: 400px;
    margin: 40px auto;
    background: #fff;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 5px 20px rgba(0,0,0,.1);
    font-family: Arial, sans-serif;
}

.redsys-box h3 {
    text-align: center;
    margin-bottom: 20px;
}

.redsys-box label {
    display: block;
    margin-top: 15px;
    font-weight: bold;
}

.redsys-box input {
    width: 100%;
    padding: 10px;
    margin-top: 5px;
    border: 1px solid #ccc;
    border-radius: 6px;
}

.redsys-box button {
    width: 100%;
    margin-top: 25px;
    padding: 12px;
    background: #0073aa;
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
}

.redsys-box button:hover {
    background: #005c88;
}