@Nosson1459, actually, they do not move a a whole group and the rows move with each other, but at slightly different times (in the original). Mine is wrong, however, in the order of row movement is botttom-up in the original, where I have it going top-down.
2019/6/6
Dialog Coding Assistant
2019/6/6
Pac-Man
2019/5/31
Dialog Coding Assistant
2019/5/30
Greenfoot Jeopardy
2019/5/29
Dialog Coding Assistant
2019/5/29
Dialog Coding Assistant
2019/5/7
Dialog Support Class
2019/5/6
Dialog Support Class
2019/5/5
Space Invaders Movement Demo