Polish footer presentation and rebalance logo sizing

[adulau]

Motivation

• Make the footer look more professional and prevent the MISP / funding logos from visually overpowering the recent-news area by rebalancing spacing, sizing and visual hierarchy.
• Provide clearer branding markup and accessibility (descriptive alt text) for the footer logos.

Description

• Replaced the inline about_us markup in config.toml with a semantic wrapper that includes a clearer "Learn more about MISP" link and descriptive alt attributes for the MISP and EU logos (file config.toml).
• Updated static/css/custom.css to give the footer a subtle gradient background, a top accent border, improved spacing and typography for headings, understated column separators, and mobile-friendly responsive adjustments (file static/css/custom.css).
• Introduced footer-specific classes to normalize logo sizing (.footer-about__logo--misp at max-width: 210px and .footer-about__logo--eu at max-width: 230px), improved recent-post dividers, and enhanced the contact button appearance.

Testing

• Ran git diff --check and found no whitespace or diff-check issues (success).
• Parsed config.toml with Python's tomllib to validate TOML syntax (success).
• Ran git status --short to verify the working tree state after the changes (success).

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Codex Task

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-29T08:01:32.377759Z	c87c3dd	PR opened
🔒 Security Review	✅ Completed 2026-09-29T08:01:42.182778Z	c87c3dd	PR opened

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