fix: Prevent jitter of refresh icon in mobile

[SHNakajima]

Closes #916

The root cause was that the .nav-buttons-container did not have a fixed minimum height, causing layout shifts when the loading animation started

Tested on:

• Obsidian Mobile (Android Pixel 8): Jitter is resolved.
• Obsidian Mobile (Android Emulator on Bluestack 720 x 1080 pixel): Jitter is resolved.
• Obsidian Desktop: No regression observed.

[Vinzent03]

I think using the variable --icon-size should be better. Could you test whether the that fixes the issue as well?

https://docs.obsidian.md/Reference/CSS+variables/Foundations/Icons

[SHNakajima]

Thank you for checking on this!

I tried using the --icon-size variable as you suggested, but unfortunately it didn't resolve the issue.

However, I discovered that simply adding .loading { overflow: hidden; } to the original styles.css (before this PR's changes) actually fixes the problem completely. This seems like a much cleaner solution.

Let me know what you think about this approach!

[Vinzent03]

Okay great. Thanks for the fix!