hehe/user/plugins/admin/themes/grav/scss/vendor/bourbon/functions/_tint-shade.scss

// Add percentage of white to a color
@function tint($color, $percent){
  @return mix(white, $color, $percent);
}

// Add percentage of black to a color
@function shade($color, $percent){
  @return mix(black, $color, $percent);
}