Release 0.1.0 - Advanced Anchor Positioning & Fallbacks

This release introduces support for several advanced CSS Anchor Positioning properties, enabling conditional visibility, fallback strategies, and anchor-based alignment. It also includes an important fix for positional utilities.

✨ New Features

• Anchor Center Utilities *-anchor → [property]: anchor-center

  • Added utilities for centering elements relative to their anchor using anchor-center.
  • Includes:
    • justify-self-anchor (justify-self: anchor-center)
    • self-anchor (align-self: anchor-center)
    • justify-items-anchor (justify-items: anchor-center)
    • items-anchor (align-items: anchor-center)
    • place-items-anchor (place-items: anchor-center)
    • place-self-anchor (place-self: anchor-center)

• Position Visibility anchored-visible-* → position-visibility: [value]

  • Control element rendering based on anchor visibility or overflow state (position-visibility).
  • Keywords:
    • anchored-visible-always (position-visibility: always): Element is always visible.
    • anchored-visible-anchor (position-visibility: anchors-visible): Visible only when the anchor element is at least partially visible.
    • anchored-visible-no-overflow (position-visibility: no-overflow): Visible only when the element itself does not overflow the viewport.
  • Supports arbitrary values: anchored-visible-[value].
  • (Note: anchors-valid is part of the spec but not yet widely supported or included).

• Position Try Order try-order-* → position-try-order: [value]

  • Define the order in which fallback positions are attempted (position-try-order).
  • Keywords:
    • try-order-normal (position-try-order: normal): Default order.
    • try-order-w (position-try-order: most-width): Prioritize fallbacks maximizing width.
    • try-order-h (position-try-order: most-height): Prioritize fallbacks maximizing height.
  • Supports arbitrary values: try-order-[value].

• Position Try Fallbacks try-* → position-try-fallbacks: [value]:

  • Define a sequence of fallback positions or strategies (position-try-fallbacks).
  • Keywords:
    • try-none (position-try-fallbacks: none): No fallbacks.
    • try-flip-x (position-try-fallbacks: flip-inline): Flip horizontally.
    • try-flip-y (position-try-fallbacks: flip-block): Flip vertically.
    • try-flip-s (position-try-fallbacks: flip-start): Flip along the writing mode's start direction.
  • Supports standard position-area keywords (e.g., try-top applies position-try-fallbacks: top, try-bottom-left applies position-try-fallbacks: bottom left)
  • Supports arbitrary values: try-[value].

🐛 Bug Fixes

• Positional Anchor Utilities: Fixed an issue where utilities like {top|right|bottom|left|inset}-anchor-{side}-{offset?} (e.g., top-anchor-bottom-4) were incorrectly configured. The offset value is now correctly optional, and the utilities properly map to the theme's inset scale values. Using top-anchor-bottom now correctly applies top: anchor(bottom) without requiring an explicit offset.