on_screen_layout_columns()
                
                on_screen_layout_columns(mixed  $columns, mixed  $screen) : integer
                Set the number of page coumns.
                
                                    Parameters
                    
                                                    
                                | mixed | 
                                $columns  | 
                                Number of Columns.  | 
                            
                                                    
                                | mixed | 
                                $screen  | 
                                Screen size.  | 
                            
                                            
                
                
                                    Returns
                    integer
                                            — $columns Number of desired page columns.