Serve the extracted Movement-Lab folder with Python 3.
macOS/Linux: python3 -m http.server 8080 --bind 127.0.0.1
Windows: py -m http.server 8080 --bind 127.0.0.1

Open http://localhost:8080/labs/01-movement.html and use arrow keys.
For the build-along, make workbench beside engine. Only the paid edition
includes the full Market Run game and the other labs.
