#display{
    width: 200%;
    padding: 20px;
    font-size: 5rem;
    text-align: left;
    border: none;
    background-color: grey;
    color: aliceblue;  
}
body{
    margin: 0;
    display: flex;
    justify-content: center ;
    align-items: center;
    height: 900%;

}
#calc{
    background-color: grey;
    border-radius: 15px;
    max-width:500px ;
    overflow: hidden;
}

#keys{
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
    padding: 20px;
}
 
button{
    width: 100px;
    height: 100px;
    border-radius: 1rem;
    border: none;
    background-color: black;
    color: aliceblue;
    font-size: 3rem;
    cursor: pointer;
}

button:hover{
    background-color: rgb(37, 36, 36);    
}
button:active{
    background-color: rgb(226, 6, 6);
    
}

.operator-btn{
    background-color: brown;
}
.operator-btn:hover{
    background-color: rgb(194, 144, 144);
}
.operator-btn:active{
    background-color: rgb(250, 54, 5);
}