bug(a11y): Mobile navigation menu is non-functional when JavaScript is disabled

Problem

When JavaScript is disabled, the primary header navigation on https://owasp.org/
becomes inaccessible. This results in a broken mobile navigation experience and
forces users to rely on footer links only.

This behavior breaks progressive enhancement principles and impacts accessibility,
particularly WCAG 2.1 Principle 4 (Robustness).

#Steps to Reproduce

1. Open https://owasp.org/
2. Disable JavaScript (Chrome DevTools → Settings → Disable JavaScript)
3. Refresh the page
4. Switch to a mobile viewport

#Actual Behavior

• Hamburger menu icon is visible but does not respond to clicks
• Primary navigation links (Chapters, Events, About) are hidden
• Search input is visible but non-functional
• Users must scroll to the footer to access navigation links

Expected Behavior

• Core navigation should be accessible without JavaScript
• Navigation should degrade gracefully when JS is unavailable
• Site should follow progressive enhancement principles

Suggested Improvement

• Provide a non-JS fallback navigation (e.g., visible list or CSS-only toggle)
• Ensure critical navigation is not JS-only
• Improve robustness for low-bandwidth or restricted environments

Environment

• Browser: Chrome / Chromium
• Condition: JavaScript disabled via DevTools

Screenshots

Related to: OWASP/www-committee-project#ISSUE_NUMBER

Start at https://owasp.org/ and reproduce the issue with JavaScript disabled in a mobile viewport, then locate the primary header navigation implementation. Done means Chapters, Events, About, and search remain usable without JavaScript and the mobile navigation degrades gracefully.