Support all modern logical properties

• Logical Properties Shim/Experimental System: Major feature extension adding support for previously unsupported CSS logical properties and values

  • New logical-shim.ts module with extensible architecture
  • SHIM_DECLARATIONS object mapping logical properties to transformation functions
  • extendProcessors() function for seamless integration with existing postcss-logical functionality
  • Minimal-impact approach that extends rather than replaces core functionality

• Scroll Properties Support: Full support for CSS scroll-related logical properties

  • scroll-margin-inline-start/end with direction-aware transformation to left/right
  • scroll-margin-block-start/end transformation to top/bottom
  • scroll-padding-inline-start/end with direction-aware transformation to left/right
  • scroll-padding-block-start/end transformation to top/bottom
  • Shorthand support: scroll-margin-inline, scroll-margin-block, scroll-padding-inline, scroll-padding-block
  • Proper value parsing for multi-value shorthands (start/end value handling)

• Logical Values Support: Support for logical values in existing CSS properties

  • float: inline-start/end → direction-aware left/right transformation
  • clear: inline-start/end → direction-aware left/right transformation
  • resize: block/inline → vertical/horizontal transformation
  • Preserves non-logical values unchanged

• Scroll Properties Support Overflow Properties (⭐ NEW via shim)

  • overscroll-behavior-block → overscroll-behavior-y
  • overscroll-behavior-inline → overscroll-behavior-x
  • overflow-block → overflow-y
  • overflow-inline → overflow-x

• Scroll Properties Support CSS Containment Properties (⭐ NEW via shim)

  • contain-intrinsic-block-size → contain-intrinsic-height
  • contain-intrinsic-inline-size → contain-intrinsic-width

• Smart Selector Priority Optimization: NEW! Advanced rightmost priority logic for predictable CSS behavior

  • Implements rightmost priority algorithm that prioritizes the most specific (rightmost) direction selector in complex selector chains
  • Handles mixed built-in (:dir(), [dir]) and custom direction selectors seamlessly
  • Eliminates unexpected behavior from contradictory direction contexts
  • Follows CSS cascade principles for intuitive results
  • Framework-agnostic support for any custom selector pattern
  • Comprehensive test coverage for edge cases and complex nested scenarios
  • New example demonstrating the optimization with real-world selector chains

• Enhanced Documentation: Comprehensive documentation improvements

  • New technical documentation (SELECTOR-PRIORITY-OPTIMIZATION.md) explaining the rightmost priority logic
  • Updated README with detailed explanations and examples of the new optimization
  • Added selector priority optimization example in examples/selector-priority/
  • Bilingual documentation (English/Chinese) for broader accessibility

Enhanced

• Property Detection: Extended logical property detection to include shim-supported properties

  • Updated supportedLogicalPropertiesSet with all shim-enabled properties
  • Improved accuracy for property classification and transformation decisions
  • Better integration between core logical properties and shim extensions

• Test Coverage: Comprehensive test suite expansion to 250 tests (100% pass rate)

  • Added unit tests for all shim functionality in logical-properties-unit.test.ts
  • Integration tests for combined shim and core features
  • Enhanced limitations-handling.test.ts with shim capability demonstrations
  • Exception handling and edge case coverage
  • CSS variables interaction testing with logical property names

• Output Optimization: Intelligent rule consolidation for better CSS output

  • Direction-independent properties consolidated in main rules
  • Direction-dependent properties separated into [dir="ltr"]/[dir="rtl"] variants only when needed
  • Reduced CSS output size through smart property grouping
  • Better performance with fewer duplicate declarations