* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Arial', sans-serif;
    background-color: #f4f4f9;
    color: #333;
}

.container {
    max-width: 500px;
    margin: 50px auto;
    padding: 20px;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

h1 {
    text-align: center;
    color: #5a67d8;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

label {
    font-weight: bold;
    display: block;
    margin-bottom: 5px;
}

select, input[type="number"] {
    width: 100%;
    padding: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 16px;
}

select:focus, input[type="number"]:focus {
    outline: none;
    border-color: #5a67d8;
}

.btn {
    width: 100%;
    padding: 12px;
    background-color: #5a67d8;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 16px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.btn:hover {
    background-color: #4c51bf;
}

#resultado {
    text-align: center;
    margin-top: 20px;
}

#valor-total {
    font-size: 24px;
    color: #48bb78;
    font-weight: bold;
}