Overview

1. This PR fixes or fixes part of #[20922].
2. This PR ensures that the "Create New Topics/Skills" button is always visible on mobile by adding a z-index of 99 to its styling. This change prevents the button from being hidden behind other elements, improving visibility and usability.
3. The original bug occurred because the button did not have a high enough z-index, causing it to be obscured by other elements on the mobile view. This made it appear only when scrolling to the bottom of the page.

Essential Checklist

Please follow the instructions for making a code change.

• I have linked the issue that this PR fixes in the "Development" section of the sidebar.
• I have checked the "Files Changed" tab and confirmed that the changes are what I want to make.
• I have written tests for my code.
• The PR title starts with "Fix #bugnum: " or "Fix part of #bugnum: ...", followed by a short, clear summary of the changes.
• I have assigned the correct reviewers to this PR (or will leave a comment with the phrase "@{{reviewer_username}} PTAL" if I can't assign them directly).

Proof that changes are correct

Before:
Shown in the issue #20922

After:
Screencast from 25-09-24 09:23:51 PM IST.webm

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