RECOMMENDATIONS

use a textured PEI sheet
- use the print profile, it has quite a few setting changes that help achieve the best results
- remove the purging lines and/or flow calibration lines during print to ovoid color fusion to the lines, this is done to maximize lightbox demensions

use the LED's the further away from the colored design possible; placing them too close ruins the diffusion and the individual LED's become visible

Bambu Studio Settings:
I always recommend using the print profile I provided since it has settings with which I've been able to get the best results.
If you choose not to here are the main slicer settings I recommend:
- preferences (ctrl + P) → activate developer settings → Quality →Advanced → First Layer Flow Ratio: 1.04
- Quality → Wall generator → Arachne
- Quality → Wall transitioning threshold angle → 50º
- Strength → Advanced → Infill/wall overlap → 20%
- Quality → Advanced → Avoid crossing walls
- Increasing retraction / reducing temperature can help reducing wisps
- Order color printing from lightest to darkest color

Happy Printing!