Mobile: Sidebar drawer leaves bottom gap when scrolling

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**Describe the bug**
On mobile devices, the sidebar drawer does not fully cover the viewport height. When scrolling, a visible gap appears at the bottom of the screen, exposing background content.

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**To Reproduce**
Steps to reproduce the behavior:

1. Open the application on a mobile device
2. Open the sidebar menu
3. Scroll the page
4. Observe a gap appearing at the bottom of the sidebar

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**Expected behavior**
The sidebar should fully cover the viewport height and remain consistent during scrolling, without leaving any visible gaps.

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**Are you going to work on fixing this?**

* [x] Yes
* [ ] No

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**Screenshots**
Attach screenshots and/or screen recording demonstrating the issue.

https://github.com/user-attachments/assets/a66ab2d7-7b28-4da7-8cab-1c51ebce5f32

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**Desktop (please complete the following information):**

* Not applicable (issue is mobile-specific)

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**Smartphone (please complete the following information):**

* Device: Samsung Galaxy S24 FE
* OS: Android
* Browser: Chrome
* Version: (optional)

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**Additional context**
This issue seems related to how viewport height is handled on mobile devices, as it only occurs on mobile and not on desktop. Further investigation may be needed to identify the exact cause.