Fixed unintended box size changes

[Atircharlotte]

Modified editor.tsx:
Changed some CSS setting of LoadSpinner component and Box component

[glassmonkey]

Hi @Atircharlotte, thanks a lot for the contribution! 🙏

Before going through the diff in detail, I'd like to understand the motivation behind this change a bit more. Could you share the following?

• What was the "unintended box size change" you observed?
• Steps to reproduce the issue.
• Before / after screenshots.
• Your environment (browser, OS, viewport size, etc.).

Thanks again!

[Atircharlotte]

Hi @glassmonkey, thank you for the feedback!

This pull request was prompted by this issue . To answer your questions:

• The "unintended box size change": I noticed that when a user toggles the HTML preview mode on and off, the width of the right-hand container shifts slightly. While this doesn't break any functionality, it creates a "jumping" effect in the UI that feels unpolished.

• Steps to reproduce:

1. Run the project locally.
2. Locate the HTML preview toggle.
3. Click the toggle repeatedly and observe the width of the container on the right side.

• Before / After:

• Environment: I am testing on a MacBook (macOS) and have confirmed that the issue occurs—and is resolved by this fix—across Safari, Chrome, and Firefox.

Let me know if you need any more details! Thanks!