| @function cs-colorblind($color, $mode: $cs-colorblind) {
  // Refrence: http://www.w3.org/TR/AERT#color-contrast
  // Deuteranopia
  @if $mode == deuteranopia {
    @return $color;
  }
  // Protanopia
  @if $mode == protanopia {
    @return $color;
  }
  // Tritanopia
  @if $mode == tritanopia {
    @return $color;
  }
  // Return color if no color blind mode.
  @else {
    @return $color;
  }
}
@function cs-cb($color, $mode: $cs-colorblind) {
  @return cs-colorblind($color, $mode);
}
 |