Fix: Navbar should remain visible when scrolling

[Udit-H]

Priority/Impact

Low (minor inconvenience)

Description

Navbar disappears when scrolling

Description

The top navigation bar disappears when scrolling down. This prevents users from accessing the navbar quickly while browsing long pages.

🔁 Steps to Reproduce

1. Visit [https://habitica.com/static/home)
2. Scroll down the page.
3. Observe that the navbar scrolls out of view.

🎯 Expected Behavior

The navbar should remain visible (sticky/fixed) at the top of the viewport when scrolling.

I would like to take this up under hacktoberfest.

[SkullShoT007]

Hi, I would like to work on this issue, can you assign me this.