public function removeClass() {
    // With no class attribute, there is no need to remove.
    if (isset($this->storage['class']) && $this->storage['class'] instanceof AttributeArray) {
      $args = func_get_args();
      $classes = array();
      foreach ($args as $arg) {
        // Merge the values passed in from the classes array.
        // The argument is cast to an array to support comma separated single
        // values or one or more array arguments.
        $classes = array_merge($classes, (array) $arg);
      }

      // Remove the values passed in from the value array. Use array_values() to
      // ensure that the array index remains sequential.
      $classes = array_values(array_diff($this->storage['class']->value(), $classes));
      $this->storage['class']->exchangeArray($classes);
    }
    return $this;
  }