Synchronizes 72 lesson files across 5 languages (de, pl, es, ar, uk) to match
the English source. This ensures code, solutions, and validations are identical
while only title, description, task, and message fields are translated.
Changes include:
- Box model lessons (01-box-model.json)
- Units and variables (05-units-variables.json)
- Transitions and animations (06-transitions-animations.json)
- Responsive design (08-responsive.json)
- HTML elements (20-html-elements.json)
- HTML forms basic and validation (21, 22)
- HTML details/summary, progress/meter (23, 24)
- HTML datalist, dialog, fieldset (25, 27, 28)
- HTML tables and SVG (30, 32)
- HTML marquee (31)
- Welcome module (00-welcome.json)
Fixes validation inconsistencies and removes extra content that exceeded
English source. German translations were largely correct; Polish, Spanish,
Arabic, and Ukrainian required full translations.
- 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)
- Wrap HTML element names in <kbd> tags in all validation messages
- Apply consistent formatting to both English and German lessons
- Make hints clearer about which elements/attributes to use
- Fix mobile editor layout overflow issue
- Remove presentational classes (.form-group, .required, .hint, .checkbox-group)
- Replace <span class="required">*</span> with plain * in label text
- Replace <div class="hint"> with semantic <small> element
- Simplify checkbox markup to use native label wrapping pattern
- Update previewBaseCSS to style semantic elements directly
- Add code quality standards to CLAUDE.md emphasizing WCAG compliance and native 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.
