Finding the piece(s) was difficult. Without a closer look, it was also hard to determine which piece I needed to drag/drop.
I would suggest filling the hole where the piece needs to go with a solid, dark color. Then you do not need any border shadow or other visual callout. It will be clear all by itself.
No opacity on the drag/drop piece (cannot tell if it has any, but looks like it might), but maybe a solid border of a few pixels. I feel like the shadow softens the piece too much, making it more difficult to locate.
If you really want to thrill your users, slightly rotate the drag/drop piece (10 degrees?), then animate the rotation back to the correct angle on mouse down. This would make that piece stand out even more, while simulating the natural interaction of a physical puzzle piece.
Overall, I really like the concept. Thanks for sharing your work, and for being open to feedback.
For further actions, you may consider blocking this person and/or reporting abuse
We're a place where coders share, stay up-to-date and grow their careers.
Finding the piece(s) was difficult. Without a closer look, it was also hard to determine which piece I needed to drag/drop.
I would suggest filling the hole where the piece needs to go with a solid, dark color. Then you do not need any border shadow or other visual callout. It will be clear all by itself.
No opacity on the drag/drop piece (cannot tell if it has any, but looks like it might), but maybe a solid border of a few pixels. I feel like the shadow softens the piece too much, making it more difficult to locate.
If you really want to thrill your users, slightly rotate the drag/drop piece (10 degrees?), then animate the rotation back to the correct angle on mouse down. This would make that piece stand out even more, while simulating the natural interaction of a physical puzzle piece.
Overall, I really like the concept. Thanks for sharing your work, and for being open to feedback.