by steps
000000 000000
000000
897880 897880
897880
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
77888f 77888f
77888f
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
66999f 66999f
66999f
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
55aaaf 55aaaf
55aaaf
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
44bbbf 44bbbf
44bbbf
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
33cccf 33cccf
33cccf
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
22dddf 22dddf
22dddf
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
11eeef 11eeef
11eeef
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff