Javascript does not work - stopwatch project

Hi,

Im practicing javascript and came across the stopwatch project as in the link below:

I tried to replicate this but the start and stop functionality does not work. I have posted my code in the link below:

I’m running this in a single index.html file in visual studio code live server.

Not sure what im missing and really appreciate any help.

Thanks
Jag

script/style tags go into <head>

Thanks for the replying @ionatan, Actually the problem was buttonStart.onClick, had capital C.

oh. I assumed you copied already functioning code and that it wasn’t loading