Build an animated explainer with code

Build an animated explainer that is drawn and played entirely by code (no image generators, no stock media).

Topic: <How lightning works>
Audience: kids <4–12>. One idea per scene, in words a 7-year-old knows.
Length: about <2> minutes, <6–9> short chapters.
Style: <flat vector / isometric / blueprint / sketch / paper cut-out / engraving / watercolor / pixel / low-poly 3D /painted oil>
Guide: a mascot who carries the story (<e.g. "Sparky the electron">): simple shape, big readable face.
Output: <interactive web page / MP4 video / both>.
Sound: synthesized music and sound effects timed to the picture (or: use this track: <file>).
Learning: short captions
Facts: accurate; tell me anything simplified.

Process:
1. Research the topic and write STORYBOARD.md: chapters, captions and cues on a beat grid. Stop and show me before building.
2. Write a style guide and a shared drawing kit, then build the chapters in parallel with subagents that check their own screenshots.
3. Review a contact sheet of every chapter, fix weak shots, and test at phone width.
4. Publish it as an artifact, and send me the link plus a contact sheet.