Fix #345: Wrap fullscreen.css in @media screen to fix print layout

[MIHIR2006]

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If your pull request closes an open issue, include the exact text below, immediately followed by the issue number. When your pull request gets merged, then that issue will close automatically.

Closes #345

[mister-roboto]

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[mister-roboto]

@MIHIR2006 thanks for creating this Pull Request and helping to improve Plone!

TL;DR: Finish pushing changes, pass all other checks, then paste a comment:

@jenkins-plone-org please run jobs

To ensure that these changes do not break other parts of Plone, the Plone test suite matrix needs to pass, but it takes 30-60 min. Other CI checks are usually much faster and the Plone Jenkins resources are limited, so when done pushing changes and all other checks pass either start all Jenkins PR jobs yourself, or simply add the comment above in this PR to start all the jobs automatically.

Happy hacking!

[mister-roboto]

@MIHIR2006 you need to sign the Plone Contributor Agreement to merge this pull request.

Learn about the Plone Contributor Agreement: https://plone.org/foundation/contributors-agreement

If you have already signed the agreement, please allow a week for your agreement to be processed.
Once it is processed, you will receive an email invitation to join the plone GitHub organization as a Contributor.

If after a week you have not received an invitation, then please contact agreements@plone.org.