body {
    font-family: Arial, sans-serif;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
}

.calculator {
    text-align: center;
    max-width: 400px;
    margin: auto;
}

label, input {
    display: block;
    margin: 10px 0;
}

button {
    background-color: #4CAF50;
    color: white;
    padding: 10px;
    border: none;
    cursor: pointer;
}

button:hover {
    background-color: #45a049;
}

#result {
    margin-top: 20px;
}