Error: Top-level selectors may not contain the parent selector "&".
  body.immobile & {
  ^^^^^^^^^^^^^^^^
  spec/libsass-issues/issue_1644/mixin-parent/input.scss 6:3  @content
  spec/libsass-issues/issue_1644/mixin-parent/input.scss 2:3  parent()
  spec/libsass-issues/issue_1644/mixin-parent/input.scss 5:1  root stylesheet
