by steps
000000 000000
000000
ffff00 ffff00
ffff00
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
e1df1f e1df1f
e1df1f
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
c4bf3f c4bf3f
c4bf3f
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
a69f5e a69f5e
a69f5e
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
89807e 89807e
89807e
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
6c609e 6c609e
6c609e
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
4e40bd 4e40bd
4e40bd
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
3120dd 3120dd
3120dd
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
1401fd 1401fd
1401fd