258     private function _is_valid_transition($val) {  argument
260         if (preg_match($pattern, $val)) return $val;
268     private function _is_valid_bg_transition($val) {  argument
270         if (preg_match($pattern, $val)) return $val;
278     private function _is_valid_color($val) {  argument
281         if (in_array($val, $named)) {
282             return $val;
286             if (preg_match($pattern, $val)) return $val;
294     private function _is_valid_image($val) {  argument
296         if (preg_match($pattern, $val)) return $val;
303     private function _is_valid_size($val) {  argument
305         if (preg_match($pattern, $val)) return $val;
312     private function _is_valid_position($val) {  argument
314         if (preg_match($pattern, $val)) return $val;