This is a simple, yet hopefully fun, puzzle game made with the LittleJS engine.  Based on the given theme: ANIMALS.  Bit challenging because there are 30 different types animals.  I suppose I'd work on improving by adding levels with lesser number of animals for easy play and working your way.  Would love feedback so that I may continue with this little project or I'm happy to leave it as is.

The list of animals, for anyone's preference/knowledge: 

1. Bear
2. Buffalo
3. Chick (yellow)
4. Chicken (greyish with some red)
5. Cow
6. Crocodile
7. Dog
8. Duck
9. Elephant
10. Frog
11. Giraffe
12. Goat
13. Gorilla
14. Hippo
15. Horse
16.  Monkey
17. Moose
18. Narwhal
19. Owl
20. Panda
21. Parrot
22. Penguin
23. Pig
24. Rabbit
25. Rhino
26. Sloth
27. Snake
28. Walrus
29. Whale
30. Zebra