body {
    font-family: Arial, sans-serif;
    background-color: #acb78e;
    margin: 0;
    padding: 20px;
    text-align: center;
}
form {
    background-color: #fff;
    padding: 20px;
    border-radius: 10px;
    max-width: 400px;
    margin: 50px auto;
}
#Absent {
    border-radius: 10px;
    padding: 20px;
    margin: 10px;
}
#Calculate{
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 10px 20px;
    text-align: center;
    text-decoration: none;
    display: inline-block;
    font-size: 16px;
    margin-top: 20px;
    cursor: pointer;
}