by steps
000000 000000
000000
ffff00 ffff00
ffff00
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
dff70f dff70f
dff70f
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
bfef1f bfef1f
bfef1f
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
9fe72f 9fe72f
9fe72f
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
7fdf3f 7fdf3f
7fdf3f
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
5fd74f 5fd74f
5fd74f
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
3fcf5f 3fcf5f
3fcf5f
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
1fc76f 1fc76f
1fc76f
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
00bf7f 00bf7f
00bf7f