use strict;
use warnings;

use Tk  qw(MainLoop);

  my $mw = MainWindow->new(  -bg => 'gold');
	
  my $ctl = $mw->Frame(-borderwidth => 1, 
                       -relief => 'solid',
                       -width => 300,
                       -bg => 'aquamarine',
                      )->pack(-fill=>'y', -expand=>1, 
                              -side=>'left', 
                              -anchor => 'w',
                             );
														
  my $cbox = $mw->Frame(-borderwidth => 1, 
                        -relief => 'solid', 
                        -width => 300,
                        -height => 500,
                        -bg => 'cornflowerblue',
                       )->pack(-fill => "both", -expand => 1, 
                               -side=>'left', 
                               -anchor => 'w',
                              );

																		
  my $sfrm = $ctl->Frame()->pack(-fill=>'y', -expand=>0, -side=>'left',);

  $sfrm->Scale(-from => 255, 
               -to => 0,
              )->pack(-fill=>'y', -expand=>1, -side=>'top',);
														 
  MainLoop();