The corners of some items are not rounded in the Assistant

### Please answer the following questions for yourself before submitting an issue

- [x] Filters were updated before reproducing an issue
- [x] I checked the [knowledge base](https://adguard.com/kb/) and found no answer
- [x] I checked to make sure that this issue has not already been filed

### AdGuard Extension version

5.1.68

### Browser version

Chrome 134.0.6998.89

### OS version

Windows 11

### Ad Blocking

_No response_

### Privacy

_No response_

### Social

_No response_

### Annoyances

_No response_

### Security

_No response_

### Other

_No response_

### Language-specific

_No response_

### What Tracking protection options do you have enabled?

_No response_

### Issue Details

Steps to reproduce:
1. Open any website.
2. Open extension and select `Block ads manually`.

### Expected Behavior

Corners of main window, buttons, bar items in advanced settings are should be rounded with `border-radius: 8px`.

### Actual Behavior

Corners of main window, buttons, bar items in advanced settings are not rounded.

### Screenshots

Old style


Old style 2


New style


New style 2


### Additional Information

_No response_