.npp-calculadora-container {
    max-width: 500px;
    margin: 30px auto;
    padding: 25px;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0,0,0,0.1);
    font-family: Arial, sans-serif;
}

.npp-calculadora-container h2 {
    text-align: center;
    margin-bottom: 10px;
}

.npp-form label {
    display: block;
    margin: 10px 0 5px;
}

.npp-form input[type="number"],
.npp-form select {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.npp-form input[type="submit"] {
    width: 100%;
    padding: 12px;
    border: none;
    border-radius: 5px;
    color: white;
    margin-top: 20px;
    font-weight: bold;
    cursor: pointer;
    transition: opacity 0.3s;
}

.npp-form input[type="submit"]:hover {
    opacity: 0.85;
}

.npp-resultado {
    margin-top: 20px;
    text-align: center;
    font-size: 20px;
    color: #333;
}