Calibration curve
The figure exactly as the kit's script produces it. Hover a mark for its precise reading.
Hover or click — the detail follows the pointer. A click pins it, which is the only way to read a value on a touch screen; Tab walks the marks from the keyboard. It is all CSS: the figure contains no JavaScript at all.
Rebuild it
python3 -m pip install -r requirements.txt && python3 make_data.py && python3 make_calibration.py
make_data.py writes data.csv, make_calibration.py reads it and draws. Edit the CSV, run again, the figure changes.