Steps to replicate the issue (include links if applicable):
- Visit a page on the docs site that has a sidebar menu (example) on mobile
- Click the "Menu" button on the left
What happens?:
The sidebar menu overlaps with the header menu:
What should have happened instead?:
The sidebar menu should be on top of the header, like it is on the VitePress docs site:
Software version (skip for WMF-hosted wikis like Wikipedia): Codex latest and main

