Hi there - great tutorial, and I see what you're doing, but I'm finding that I can't make it work. Not sure what I'm doing wrong. I forked the code and cloned it to my local, pointed chrome to the index.html page, and expected magic. Instead, the only thing I get when I click on the button is a click with no javascript.
The thing that's funny is that I can run the demos on the page just fine in the same browser. I get no errors, it just doesn't seem to be running the onclick event somehow.
I'm running chrome Version 54.0.2840.71 (64-bit).
Here's a screenshot of what I'm looking at:

The JS fires. It just doesn't do anything but repaint the button. What am I missing here?
Thanks in advance.
Scott