The colors in this do NOT render well to the 256 colors of the .gif format (especially at the 3MB cap of itch.io!). Look at the screenshots for what it actually looks like, the .gif is just for proof that Bolt is doing the work.
-Edit- Okay, changed the proof gif to a better gif of the bubble spawn code, which is easily verifiable that it is in-sync with the gameplay actions. See the gifs in the comments for more interesting gifs.