Pages shift after clicking on a nav menu tab

Hi there,
I noticed that on the desktop breaking point whenever I click on any page tab in the nav bar, the whole page and the nav bar shifts to a side, left or right.
I wasn’t able to find the reason for it. Ideally I’d like the nav bar to remain locked and that the pages load up in the same spot every time.
Another minor inconvenience is that when the cursor hovers over a button, it doesn’t change into a hand indicating it’s a clickable link. I noticed as well that for some reason only on chrome the Bio link on the homepage isn’t clickable.

I appreciate your help.

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