Small UI tweaks

[TamaroWalter]

🔀 Purpose of this PR:

• Fixes a bug
• Updates for a new Moodle version
• Adds a new feature of functionality
• Improves or enhances existing features
• Refactoring: restructures code for better performance or maintainability
• Testing: add missing or improve existing tests
• Miscellaneous: code cleaning (without functional changes), documentation, configuration, ...

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📝 Description:

A short PR. Adds a missing margin and cleans css code.

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📋 Checklist

• Code passes the code checker without errors and warnings.
• Code passes the moodle-ci/cd pipeline on all supported Moodle versions or the ones the plugin supports.