@mixin surface($color: black){
    @if $color == black{
        color: white;
        background-color: green;
    }@else if $color == white{
        color: red;
        background-color: black;
    }@else{
        color: #c6c6c6;
        background-color: #00ffff;
    }
    &::after{
        content: 'Colored';
        color: $color;
        background-color: blue;
        &:hover{
            transform: scale(2);
        }
    }
    &:hover{
        transform: translateX(10%);
    }
}