body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    margin: 0;
    padding: 0;
}

.container {
    max-width: 500px;
    margin: 50px auto;
    padding: 20px;
    background-color: #fff;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    border-radius: 5px;
}

h1 {
    text-align: center;
    color: #333;
}

form {
    display: flex;
    flex-direction: column;
}

label {
    margin-bottom: 5px;
    color: #555;
}

input[type="number"] {
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
}

input[type="submit"] {
    padding: 10px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    font-size: 18px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

input[type="submit"]:hover {
    background-color: #218838;
}

#result {
    margin-top: 20px;
    padding: 15px;
    background-color: #f8f9fa;
    border-radius: 5px;
    border: 1px solid #ddd;
}