So I'm trying to explore this code locally. I've saved all the files referenced in it, updated any file paths that need changed and have deployed a web server (via the cmd line) on the folder where the page is saved, and the vast majority of it loads in my web browser and looks correct.

But when I try to interact with it the way I do on the live site, something is breaking and I'm not sure what it is or how to fix it. The page just isn't updating, primarily. The lines from airport to airport aren't showing up and I can't even clear the map.

I've supplied some images of the error and all the files I have saved, plus what the page looks like for me.

Is there a better/simpler way to do this? Or is there an easy fix to keep doing it the way that I'm trying to?

(I don't know if this sort of tinkering with other people's code is frowned upon so I apologize if this is some sort of faux pas)