body{
       height: 100vh;
       margin: auto;
       display: flex;
       align-items: center;
       justify-content: center;
}
#calculator{
       height: 390px;
       width: 290px;
       border: 2px solid black;
       border-radius: 20px;
       background-color: rgb(83, 240, 187);
       border: none;
       box-shadow: 5px 5px 40px;
}
input{
       padding: 7px;
       width: 230px;
       height: 35px;
       margin-top: 40px;
       background-color: rgb(107, 122, 120);
       border: none;
       outline: none;
       border-radius: 9px;
       color: white;
       font-size: 21px;
}

#buttons{
    margin-top: 25px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 12px;
    padding: 0 21px;
}

#buttons button{
    height: 48px;
    font-size: 20px;
    border: none;
    border-radius: 10px;
    background-color: rgb(23, 150, 133);
    color: white;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(104, 83, 83, 0.3);
}