fix(Grid): add spacing between stripe and bottom bar

[DorraJaouad]

☑️ Resolves

• Follow-up to feat(call): redesign of Call view #15583

• add spacing between stripe and bottom bar
• Restore highlighted screen share button when screensharing
• Add shadow on own video when one-to-one
• Reduce gap in split button

🖌️ UI Checklist

🖼️ Screenshots / Screencasts

🏚️ Before	🏡 After

🏁 Checklist

• 🌏 Tested with different browsers / clients:
  • Chromium (Chrome / Edge / Opera / Brave)
  • Firefox
  • Safari
  • Talk Desktop
  • Not risky to browser differences / client
• 🖌️ Design was reviewed, approved or inspired by the design team
• ⛑️ Tests are included or not possible
• 📗 User documentation in https://github.com/nextcloud/documentation/tree/master/user_manual/talk has been updated or is not required

[DorraJaouad]

Here I think I added a 16px right and bottom margin and a shadow

@nimishavijay
I added instead 8px spacing to mimize waste of space. I am not sure however about the shadow as there will also be videos of other participants on that stripe. Is it okay to have only shadow on own video?

[nimishavijay]

8px looks good to me 👍Adding the gap already improved the look. Nice-to-have: Could we add the shadow if there is only your video in the participants stripe? i.e 1on1s and group calls where only 1 other person has joined?