code: function normalize(property, value, prefix){
    var result = value.toString(),
        args;
  
    /* Fixing the gradients */
    if (~result.indexOf('gradient(')) {
  
      /* Normalize color stops */
      result = result.replace(RE_GRADIENT_STOPS,'$1$4$3$2');
  
      /* Normalize legacy gradients */
      result = result.replace(RE_GRADIENT_VAL, function(){
          args = [].slice.call(arguments, 1);
          return normalizeGradient(args, prefix);
      });
  
      /* Adding prefixes to the legacy gradients */
      if (prefix) result = result.replace(RE_GRADIENT_TYPE, '-' + prefix + '-$1');
    }
  
    /* Adding prefixes to the `transform` values of legacy `transition` property */
    if (prefix && (property == "'transition'" || property == "'transition-property'")) {
      result = result.replace(RE_TRANSFORM, '-' + prefix + '-$1');
    }
  
    /* Removing `fill` keyword from the legacy `border-image` property */
    if (prefix && (property == "'border-image'" || property == "'border-image-slice'")) {
      result = result.replace(RE_FILL_KEYWORD, ' ');
    }
  
    return result;
  }
docs: Expose `normalize`.