Rewrite ~120 validation error messages across 17 English lesson modules
and their localized variants (ar, de, es, pl, uk) to use concept questions,
property hints, and directional nudges instead of revealing the exact
CSS property-value answers.
Priority modules (flexbox, box-model, colors, positioning) fully rewritten.
All remaining CSS modules updated. Only message strings changed — no
validation logic modifications.
- Updated de, pl, es, ar, uk translations to have identical structure
- All 10 lessons now match English: code, solutions, validations
- Only title, description, task, and message fields are translated
- Removed obsolete lessons not present in English version
🤖 Generated with [Claude Code](https://claude.com/claude-code)
- Shorten German module titles with consistent HTML/CSS prefixes
- Add .completion-badge styling for the lesson title completion badge
- Make sidebar lessons section fill available height on desktop
- Improve flexbox lesson descriptions with more context
- Replace single quotes with <kbd> tags in validation messages
- German and English lessons updated for consistent formatting
- Move task instruction before description in UI (index.html)
- Add German HTML entry point (index.de.html)
- Add German app.js with translated UI strings (app.de.js)
- Add German lesson config (lessons.de.js)
- Add German translations of all 6 lesson modules:
- HTML Elements: Block vs Inline
- HTML Forms: Basic Inputs
- HTML Forms: Validation
- CSS: Basic Selectors
- CSS: Advanced Selectors
- Tailwind: Basics
All IDs, variable names, and code examples remain in English.
Only user-facing text has been translated to German.
