Fixed issue where cards appeared to pivot around the grab point in
viewport space instead of rotating around their own center.
The problem: When dragging, the card would stay "pinned" at the grab
point in screen space, making it rotate around that viewport location.
The solution: As the card rotates, calculate the rotated grab offset
and reposition the card so that:
1. The grab point stays under the cursor
2. The card rotates around its own center
3. The visual result feels like the card is "stuck" to your finger
Implementation:
- Convert rotation angle to radians
- Apply 2D rotation matrix to grab offset vector
- Calculate card center position: cursor - rotated grab offset
- Convert center position to top-left for CSS translate positioning
This creates the natural feeling of grabbing and spinning a physical
card by its edge.
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
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