Mobile NavMenu makes hidden slider viewable

I’m having issues in the mobile format.
First, the Nav Menu when viewing the work page only stickies to the top until I scroll halfway down.
Second, in mobile portrait, when I click on a page from the drop-down nav menu it will make the hidden slider from the landing page visible along with whatever page I clicked.
I didn’t set up separate pages, just animation interactions to make content visible or invisible depending on which page is clicked. Still, I’m not seeing the same problems in the mobile landscape.


Here is my site Read-Only: Portfolio Site