by steps
000000 000000
000000
7f7f7f 7f7f7f
7f7f7f
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
7c7d7e 7c7d7e
7c7d7e
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
797c7e 797c7e
797c7e
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
767b7d 767b7d
767b7d
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
737a7d 737a7d
737a7d
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
70797d 70797d
70797d
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
6d787c 6d787c
6d787c
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
6a777c 6a777c
6a777c
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
67767c 67767c
67767c