by steps
000000 000000
000000
00ffff 00ffff
00ffff
00007f 00007f
00007f
0000ff 0000ff
0000ff
007f00 007f00
007f00
007f7f 007f7f
007f7f
10fee7 10fee7
10fee7
007fff 007fff
007fff
00ff00 00ff00
00ff00
00ff7f 00ff7f
00ff7f
20fecf 20fecf
20fecf
7f0000 7f0000
7f0000
7f007f 7f007f
7f007f
30feb7 30feb7
30feb7
7f00ff 7f00ff
7f00ff
7f7f00 7f7f00
7f7f00
7f7f7f 7f7f7f
7f7f7f
40fe9f 40fe9f
40fe9f
7f7fff 7f7fff
7f7fff
7fff00 7fff00
7fff00
7fff7f 7fff7f
7fff7f
7fffff 7fffff
7fffff
50fd87 50fd87
50fd87
ff0000 ff0000
ff0000
ff007f ff007f
ff007f
ff00ff ff00ff
ff00ff
60fd6f 60fd6f
60fd6f
ff7f00 ff7f00
ff7f00
ff7f7f ff7f7f
ff7f7f
ff7fff ff7fff
ff7fff
70fd57 70fd57
70fd57
ffff00 ffff00
ffff00
ffff7f ffff7f
ffff7f
ffffff ffffff
ffffff
81fd3f 81fd3f
81fd3f