by steps
000000 000000
000000
ffffff ffffff
ffffff
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
f9fbfe f9fbfe
f9fbfe
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
f4f8fd f4f8fd
f4f8fd
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
eff4fc eff4fc
eff4fc
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
eaf1fc eaf1fc
eaf1fc
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
e4edfb e4edfb
e4edfb
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
dfeafa dfeafa
dfeafa
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
dae6f9 dae6f9
dae6f9
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
d5e3f9 d5e3f9
d5e3f9