body{
    background-color: burlywood;
    text-align: center;
}
.calculator{
    padding: 20px;
    margin: 0 auto;
    width: 300px;
    background-color: white;
    border-radius: 15px;
}
input{
    height: 40px;
    text-align: right;
    font-size: 20px;
    margin-bottom: 20px;
}
button{
    height: 50px;
    width: 60px;
    margin: 5px;
    font-size: 20px;
    font-weight: bold;
    cursor: pointer;
    border: none;
    border-radius: 15px;
}
button:active{
    background-color: burlywood;
}