Keyboard focus going on hidden elements in smaller resolutions

**Describe the bug**
When Navigation items are opened on smaller resolutions and keyboard is used for navigation elements on the page then focus goes to page elements (which are actually hidden) after nav list.

**To Reproduce**
Steps to reproduce the behavior:
1. Go to https://accessibleweb.dev/ (in mobile view)
2. Click on hamburger menu icon on top right
3. Use keyboard to navigate through focusable elements
4. Focus will move to hidden elements after completing nav list

**Expected behavior**
Focus should not move to hidden elements.

**Recording**
https://github.com/AccessibleForAll/AccessibleWebDev/assets/17885747/7f25aeb7-878f-4b56-8f50-5d6b10c3d4ee