<===> options.yml
---
:ignore_for:
- dart-sass

<===> input.scss
@mixin opacity($percent) {
  foo { test: opacity($percent); }
}

@-webkit-keyframes uiDelayedFadeIn {
  0% { @include opacity(0.01); }
  50% { @include opacity(0.01); }
  100% { @include opacity(1); }
}

@-webkit-keyframes bounce {
  from {
    left: 0px;
  }
  to {
    left: 200px;
  }
}

<===> output.css
@-webkit-keyframes uiDelayedFadeIn {
  0% {
    foo {
      test: opacity(0.01);
    }
  }
  50% {
    foo {
      test: opacity(0.01);
    }
  }
  100% {
    foo {
      test: opacity(1);
    }
  }
}
@-webkit-keyframes bounce {
  from {
    left: 0px;
  }
  to {
    left: 200px;
  }
}