- Reduced canvas minHeight (400→250) and MIN_SIZE (350→250) to minimize gray space
- Added 20px bottom padding to prevent canvas from overlapping box widgets and node border
- Added visible emoji-labeled headers to all prompt inputs:
* 🌍 Background Prompt
* 📍 Region 1-4
- Improved widget label clarity for better user experience
These changes address user-reported issues with canvas positioning and
lack of clear region identification in the node UI.