Mixin - Not

not.scss

/*/////////////////////////////////////////
/// NOT
*/////////////////////////////////////////

 @mixin not($ignorList...) {
    //if only a single value given
    @if (length($ignorList) == 1){
        //it is probably a list variable so set ignore list to the variable
        $ignorList: nth($ignorList,1);
    }
    //set up an empty $notOutput variable
    $notOutput: '';
    //for each item in the list
    @each $not in $ignorList {
        //generate a :not([ignored_item]) segment for each item in the ignore list and put them back to back
        $notOutput: $notOutput + ':not(#{$not})';
    }
    //output the full :not() rule including all ignored items
    &#{$notOutput} {
        @content;
    }
}