Как сделать подсветку запрашиваемых слов в результатах поиска?

?>

function hilites($search, $txt) {
    $r = preg_split( '((>)|(<))', $txt, - 1, PREG_SPLIT_DELIM_CAPTURE );
                    
    for($i = 0; $i < count( $r ); $i ++) {
        if( $r[$i] == "<" ) {
            $i++;
            continue;
        }
        $r[$i] = preg_replace( "#($search)#i", "<span style='background-color:yellow;'><font color='red'>\\1</font></span>", $r[$i] );
    }
    return join( "", $r );
}

            }
        }
    }
    
    $tpl->clear();

                // hilites
                if( $config['full_search'] ) $arr = explode( " ", $story );
                else $arr = explode( "%", $story );
                    
                foreach ( $arr as $word ) {
                        if( strlen( trim( $word ) ) >= $config['search_length_min'] ) {
                        $tpl->result['content'] = hilites( $word, $tpl->result['content'] );
                    }
                }
                // hilites