by steps
000000 000000
000000
ffff00 ffff00
ffff00
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
f6ff01 f6ff01
f6ff01
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
eeff02 eeff02
eeff02
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
e6ff03 e6ff03
e6ff03
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
deff04 deff04
deff04
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
d6ff05 d6ff05
d6ff05
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
ceff06 ceff06
ceff06
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
c6ff07 c6ff07
c6ff07
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
beff09 beff09
beff09