Controller help

Hi, I'm totally new to gaming, so please be gentle with me...

I found hollowknight.io a few days ago and I love it, but I've been playing with a keyboard, and I'm really struggling to defeat the Husk Guards, nevermind the boss in the Hidden Crossroads, so I bought my very first games controller in the hope that it would (once I've got my head around how it works) give me a bit more control and help in progressing in the game.

I've seen some of the other posts where people have had problems, but I can't find a solution. I'm playing the game on google chrome, on a macbook. The macbook will identify the controller (it'll rumble it), and when I go to the "controller" section of the game, it seems to see that it's connected, but when I'm in the game... nada!

Has anybody come across this before? Is it fixable? Also, as I'm still pretty close to the beginning, so won't loose a huge amount of play, is buying the game on Steam and using the controller with that easier and more reliable?

Thanks folks.