Hope I’m not too late.
Entry for the graphic competition
Image shows screenshot. This is running on an Atari 2600.
To run the binary on Atari 2600, banks witch scheme is 3E (Stella emulator will auto-detect).
Right-difficulty switch (before power-on) to A for PAL or to B for NTSC.

Notes/comments.
The Atari 2600 has just 40 pixels across the screen. These pixels can be a single colour only.
This demo shows what I refer to as “interleaved chronocolour” graphics, which achieves colours by modifying the single colour every scanline and switching pixels on/off in groups of 3 scaliness. Thus a single “ICC” pixel is 3 scanlines high, and is a blend of the colours, depending on which pixels on the line are on, and which are off. In effect there are 8 colours available for each pixel. It is further complicated by variation in those 3-colours down the screen; in this image/demo there is a subtle fade in effect which can (just) be seen in the sides of the blue box.

This is the title screen for a new Atari 2600 game I am developing, a sokoban clone. Full-colour screens on the system are previously unknown.
Chris Mylrae who is doing the amazing sound/music for this project.