improve banner styling when switching languages

[100xmanas]

Fixes #3684

Description:
This PR improves the styling of the banner message when users switch languages.

before

500286459-e943c814-e7e3-40fd-82b0-7bf538e3475c.mov

After

1018.mp4

Changes:

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123
• meets the standards outlined in the accessibility guidelines