*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}
.container{
    width: 100%;
    height: 100vh;
    background: #eaf9ff;
    align-items: center;
    justify-content: center;
    display: flex;
}
.group{
    padding: 20px;
    background: #3a4452;
    border-radius: 10px;
}
.group form input{
    border: 0;
    outline: 0;
    width: 60px;
    height: 60px;
    border-radius: 10px;
    box-shadow: -8px -8px 15px rgba(225, 225, 225, 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;
    background: transparent;
    width: 300px;
    height: 50px;
    color: #fff;
    font-weight: bold;
    font-size: 45px;
    border-radius: 10px;
    box-shadow: none;
}
form input.equal{
    width: 145px;
}
form input.operator{
    color: #33ffd8;
}