by steps
000000 000000
000000
7f0000 7f0000
7f0000
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
701f0f 701f0f
701f0f
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
613e1e 613e1e
613e1e
00ffff 00ffff
00ffff
7f007f 7f007f
7f007f
525e2e 525e2e
525e2e
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
437d3d 437d3d
437d3d
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
349c4c 349c4c
349c4c
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
25bc5c 25bc5c
25bc5c
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
16db6b 16db6b
16db6b
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
07fb7b 07fb7b
07fb7b