body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f9;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    margin: 0;
}
.calculator {
    background-color: white;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.1);
    max-width: 400px;
    width: 100%;
}
h1 {
    font-size: 24px;
    margin-bottom: 10px;
}
.input-group {
    margin-bottom: 15px;
}
label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}
input[type="number"] {
    width: 100%;
    padding: 8px;
    font-size: 16px;
    border-radius: 4px;
    border: 1px solid #ccc;
}
input[type="number"].error-field {
    border: 2px solid red;
    background-color: #ffe5e5;
}
.result {
    margin-top: 20px;
    font-size: 18px;
    font-weight: bold;
}
.error {
    color: red;
    margin-top: 10px;
}
.formula {
    font-size: 16px;
    background-color: #f8f8f8;
    padding: 10px;
    border-radius: 4px;
    margin-bottom: 20px;
    border: 1px solid #ddd;
}
.button-group {
    margin-top: 20px;
}
button {
    padding: 10px 20px;
    font-size: 16px;
    border: none;
    border-radius: 4px;
    background-color: #007bff;
    color: white;
    cursor: pointer;
}
button:hover {
    background-color: #0056b3;
}
.other-button {
    padding: 10px 20px;
    font-size: 16px;
    border: none;
    border-radius: 4px;
    background-color: #007bff9f;
    color: white;
    cursor: pointer;
}
.other-button:hover {
    background-color: #0057b357;
}