🎨 Palette: Semantic and accessible navigation

[ISTEC-FOR340]

🎨 Palette: Semantic and accessible navigation

💡 What

Refactored the project's navigation system to use semantic HTML <a> tags instead of JavaScript onclick handlers on div and button elements.

🎯 Why

The previous implementation was inaccessible to keyboard users and screen readers, and it broke standard browser features like "Open in new tab". By using semantic links, we improve accessibility, SEO, and the overall robustness of the application.

♿ Accessibility

• Semantic Links: Used <a> tags for all navigation elements.
• Focus States: Added high-contrast :focus-visible rings to cards and buttons to ensure clear visual feedback during keyboard navigation.
• Valid HTML: Converted nested buttons to spans within link cards to avoid invalid nested interactive elements.
• Language Metadata: Ensured lang="es" is set across all pages for consistency with the ISTEC educational target audience.

✅ Verification

• Verified keyboard navigation (Tab and Enter) using Playwright.
• Confirmed focus indicators are visible and follow the design system.
• Deleted script.js as it is no longer required for navigation.

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PR created automatically by Jules for task 4085075305909633334 started by @ISTEC-FOR340

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