fix(core): :bug: fixes css

[priyanshu2k3]

fixes css

ref #423

Description

addes the css and timer to remove the snackbar

Testing

manual testing done by myself

Checklist

• [ ] I have performed a thorough self-review of my code.
• [ ] I have added or updated relevant tests for my changes.
• [ ] My code follows the project's style guidelines and best practices.
• [ ] I have updated the documentation if necessary.
• [ ] I have added or updated relevant comments in my code.
• [ ] I have resolved any merge conflicts of my branch.

Screenshots (if applicable)

Additional Notes

Reviewers

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Maintainer Notes

• [ ] Has this change been tested in a staging environment?
• [ ] Does this change introduce any breaking changes or deprecations?