D3 Codepens seem to be corrupted

This CodePen is no longer displaying the correct sample contet

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/88.0.4324.190 Safari/537.36.

Challenge: Visualize Data with a Heat Map

Link to the challenge:

It’s working now. thanks