virt2/assets/vendor_components/bootstrap/scss/mixins/_text-emphasis.scss

// Typography

@mixin text-emphasis-variant($parent, $color) {
  #{$parent} {
    color: $color !important;
  }
  a#{$parent} {
    @include hover-focus {
      color: darken($color, 10%) !important;
    }
  }
}