This is essentially a case for an Adafruit Circuit Playground Bluefruit. Any Circuit Playground will fit, but a Bluefruit one will allow you to change colors and such from the Adafruit app.

This is made in two pieces that screw together. I made the top in a translucent/clear material to let the light shine through. The pieces are pretty tight, but if you keep working them or use a tiny bit of lubricant, they will go together.

There is a hole for a switch, and a hole for the micro usb. Depending on the size of the usb connector, you may need to file the hole a little larger. (it is set a ways back)

https://www.adafruit.com/product/4333

Note: I had previously posted this a couple of years ago on Thingiverse.