style.css

*{
    margin: 0;
    padding:0;
    font-family:'Poppins',sans-serif;
    box-sizing: border-box;
}

.container{
    width:100vw;
    height:100vh;
    background: #9be0f3;
    display: flex;
    align-items: center;
    justify-content: center;
}
.calculator{
    background: #1c1c1c;
    padding:20px;
    border-radius: 10px;
}
.calculator form input{
    border:0;
    outline:0;
    width:60px;
    height:60px;
    border-radius: 50%;
    box-shadow: -8px -8px 15px rgba(255,255,255,0.1), 5px 5px 15px rgba(0,0,0,0.2);
    background:transparent;
    font-size: 20px;
    color:#fff;
    cursor:pointer;
    margin:10px
}
form .display{
    display: flex;
    justify-content: flex-end;
    margin: 20px 0;
}
form .display input{
    text-align:right;
    flex:1;
    font-size:45px;
    box-shadow: none;
    border-radius: 0;
}

/* form input.equal{
    width:145px;
    border-radius:16px;
} */
 form input.operator{
    background: #ff9500;
 }

 form input.special{
    background: #d4d4d2;
 }