"I can resize my width too", that is really cool of you, but it would be nice if you also didn't go beyond my screen edge. Especially if the Next button is there.

Also consider adding push history support or whatever that's called. I'd like to click back in my browser to go back in the intro.

This is mostly because the back/forth touchpad gesture added in some version of MacOS or another, combined with the back/forth buttons on the mouse I use on the linux machine, have made me big users of the Back functionality. Something I would never click on "manually" and wouldn't even consider exists otherwise[1].

[1] Before those two developments I spent 5+ years convinced that nobody ever clicks Back in a browser.