Fix: remove the dark side bars from the Now Playing card

[SandObserver]

Summary

• Remove the Now Playing page's own inset ring and top highlight, which left dark 1px bars on the card's left and right edges under the card edge light.

Testing
All green.

Changelog

Checklist

• Stays within the project constraints: one container, no runtime dependencies, no build step (see CONTRIBUTING.md).
• Tests added or updated for new logic, and the full suite, lint, and typechecks pass.
• Docs updated if behavior or configuration changed.