body {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    margin: 0;
    background-color: #f0f0f0;
}

.calculator-box {
    background-color: #ffffff;
    border-radius: 12px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    padding: 20px;
    width: 300px;
    text-align: center;
}

#calculateBtn {
    margin-top: 15px;
}

.calculator-box label {
    display: block;
    font-weight: 600;
    margin: 10px 0;
}

.calculator-box input {
    width: calc(100% - 20px);
    padding: 10px;
    margin: 5px 0;
    border: 1px solid #dddddd;
    border-radius: 6px;
    box-sizing: border-box;
    outline: none;
}

.calculator-box button {
    width: 100%;
    padding: 12px;
    border: none;
    border-radius: 8px;
    background-color: #4caf50;
    color: white;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
}

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