#770 - Moved stylesheets to appropriate places and refactored imports

[Ari-S-123]

Changes

Moved all remaining stylesheets to appropriate places and refactored imports.

Checklist

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• [x] All commits are tagged with the ticket number
• [x] No linting errors
• [x] No newline at end of file warnings
• [x] All code follows repository-configured prettier formatting
• [x] No merge conflicts
• [x] All checks passing
• [ ] Screenshots of UI changes (if applicable)
• [x] Remove any not-applicable sections
• [x] Assign the PR to yourself
• [x] PR is linked to the ticket
• [x] No package-lock.json changes (unless dependencies have changed)
• [x] Request reviewers & ping on Slack

Closes #770

[jamescd18]

Is there any de-duplication that can be done across these 16 stylesheets?