Versatile Light Box

For a while I've wanted to create a universal light box frame which allows makers to insert their own picture and artwork designs. The idea is to have a generic box with a slot into which printed designs can be inserted. I also wanted to take advantage of close to the maximum size which can be printed on my Bambu Labs P1P. I also realised that there are different thicknesses of picture which may need to be inserted. For example the usual light box picture may be 1mm and a lithophane or HueForge