Another remix from Bonsaiheldin's Treasures Chests https://opengameart.org/content/treasure-chests-32x32#comment-105109

But this time followin the retro 8Bit constraints and 3 visible colors
It has a 4 frame aimation fr opening/closing.

- 1 version with solid black background
- 1 version with alpha borders, to cheat a 4th color by using the background color as an outline
- 1 version with 3 solid colors (no black) and an alpha background
- 1 RGB mask with alpha outline
- 1 RGB mask with alpha background