Subtly highlight last played move

[jjst]

This would help figure out what was the last move played by your opponent, especially useful in remote games or games against the AI.

Probably requires a model change to keep track of what the last move was.

On the view side the change might be a bit complicated as it will most likely require passing down what the last move was in order to do some style trickery to highlight it.

[jjst]

Could use an SVG animation that makes the move progressively appear, or fade in and fade out

[jjst]

Something like this: https://jsfiddle.net/8k0rLbt5/

[jjst]

Done purely in CSS by styling the SVG! In 60dc4c1

[jjst]

There's some bugs, but it mostly works :D