There are a number of websites out there that help you design boxes on laser cutters. I picked one pretty much at random and was fairly quickly able to put together this box. Not bad, I thought, but I do think that the stripy edge is a bit distracting.
I dropped the file into Illustrator and took out most of the castellations leaving these simpler parts. The piece, top left is a rectangle of 1mm thick clear acrylic. I cut out the parts on my laser cutter then the whole thing then just snaps together.
…and makes this rather attractive display case. I much prefer the design with just the corners dark.