<===> input.scss
@mixin mixin()
{
	& .class
	{
		color: black;
	}
}

@include mixin();
<===> error
Error: Base-level rules cannot contain the parent-selector-referencing character '&'.
        on line 3 of input.scss, in `mixin'
        from line 9 of input.scss
  Use --trace for backtrace.

<===> error-libsass
Error: Top-level selectors may not contain the parent selector "&".
        on line 9:10 of input.scss
>>      & .class

<===> error-dart-sass
Error: Top-level selectors may not contain the parent selector "&".
  ,
3 | /     & .class
4 | |     {
  | '----^
  '
  input.scss 3:2  mixin()
  input.scss 9:1  root stylesheet