by steps
000000 000000
000000
ffff00 ffff00
ffff00
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
f5fe02 f5fe02
f5fe02
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
ecfe05 ecfe05
ecfe05
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
e2fd07 e2fd07
e2fd07
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
d9fd0a d9fd0a
d9fd0a
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
cffc0d cffc0d
cffc0d
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
c6fc0f c6fc0f
c6fc0f
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
bcfb12 bcfb12
bcfb12
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
b3fb15 b3fb15
b3fb15