by steps
000000 000000
000000
ffffff ffffff
ffffff
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
dfefee dfefee
dfefee
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
bfdfde bfdfde
bfdfde
00ffff 00ffff
00ffff
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
9fcfce 9fcfce
9fcfce
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
80c0be 80c0be
80c0be
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
60b0ae 60b0ae
60b0ae
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
40a09e 40a09e
40a09e
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
20908e 20908e
20908e
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
01817e 01817e
01817e