#roi-calculator {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    max-width: 500px;
    margin: auto;
}

#roi-calculator h2, #roi-calculator div {
    color: #333;
}

#roi-calculator label {
    display: block;
    margin-top: 20px;
}

#roi-calculator input[type="text"], #roi-calculator input[type="number"] {
    width: 100%;
    padding: 10px;
    margin-top: 5px;
    border: 1px solid #ccc;
    border-radius: 4px;
}

#roi-calculator button {
    background-color: #007bff;
    color: white;
    padding: 10px 15px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    display: block;
    width: 100%;
    margin-top: 20px;
}

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