assets/sass/bourbon/bourbon/utilities/_lightness.scss

   1 @charset "UTF-8";
   2
   3 /// Programatically determines the lightness of a color.
   4 ///
   5 /// @argument {color (hex)} $hex-color
   6 ///
   7 /// @return {number (0-1)}
   8 ///
   9 /// @example scss
  10 ///   _lightness($color)
  11 ///
  12 /// @access private
  13
  14 @function _lightness($hex-color) {
  15   $-local-red-raw: red(rgba($hex-color, 1));
  16   $-local-green-raw: green(rgba($hex-color, 1));
  17   $-local-blue-raw: blue(rgba($hex-color, 1));
  18
  19   $-local-red: _gamma($-local-red-raw / 255);
  20   $-local-green: _gamma($-local-green-raw / 255);
  21   $-local-blue: _gamma($-local-blue-raw / 255);
  22
  23   @return $-local-red * 0.2126 + $-local-green * 0.7152 + $-local-blue * 0.0722;
  24 }