body {
    font-family: Arial, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #f0f0f0;
}

.calculator-container {
    background: #fff;
    padding: 2em;
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    text-align: center;
}

.input-group {
    margin: 1em 0;
}

label {
    display: block;
    margin-bottom: 0.5em;
    font-weight: bold;
}

input[type="date"] {
    padding: 0.5em;
    border-radius: 4px;
    border: 1px solid #ccc;
    font-size: 1em;
}

button {
    padding: 0.75em 1.5em;
    background-color: #007BFF;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1em;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #0056b3;
}

#result {
    margin-top: 1.5em;
    font-size: 1.2em;
    font-weight: bold;
    color: #333;
}