code: function desaturate(color, amount) {
      amount = (amount === 0) ? 0 : (amount || 10);
      var hsl = tinycolor(color).toHsl();
      hsl.s -= amount / 100;
      hsl.s = clamp01(hsl.s);
      return tinycolor(hsl);
  }
docs: Modification Functions ---------------------- Thanks to less.js for some of the basics here <https://github.com/cloudhead/less.js/blob/master/lib/less/functions.js>