Add missing light mode border in Community section

[Adityakumar37]

What kind of change does this PR introduce?

A bugfix — added missing border for the Community section cards in Light Mode.

Issue Number:

• Closes #1926

Screenshots/videos:

If relevant, did you update the documentation?

Not applicable.

Summary

This PR fixes the missing border in Light Mode for the community cards (Slack, Blog, and GitHub links).
Dark mode styles are untouched.
This improves the visual consistency and UI clarity in Light Mode.

Does this PR introduce a breaking change?

No breaking changes introduced.

Checklist

• [x] Read, understood, and followed the contributing guidelines.

[github-actions[bot]]

built with Refined Cloudflare Pages Action

⚡ Cloudflare Pages Deployment

Name	Status	Preview	Last Commit
website	✅ Ready (View Log)	Visit Preview	afc6dc03529a4002445f90ebd5a03f16981d75c9

[codecov[bot]]

Codecov Report

:white_check_mark: All modified and coverable lines are covered by tests. :white_check_mark: Project coverage is 100.00%. Comparing base (dcf4ea4) to head (afc6dc0). :warning: Report is 16 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##              main     #1945   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           30        30           
  Lines          633       633           
  Branches       196       196           
=========================================
  Hits           633       633           

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

:rocket: New features to boost your workflow:

• :snowflake: Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• :package: JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.