by steps
000000 000000
000000
7fff7f 7fff7f
7fff7f
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
7fe77f 7fe77f
7fe77f
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
80cf7f 80cf7f
80cf7f
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
81b87f 81b87f
81b87f
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
82a07f 82a07f
82a07f
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fffff 7fffff
7fffff
82887f 82887f
82887f
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
83717f 83717f
83717f
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
84597f 84597f
84597f
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
85427f 85427f
85427f