You can of course do it in either, however here are a few notes to help you decide which to choose…
If you choose CSS…
- CSS is simpler to learn - if you are designer and do not like or want or have the time to learn code, using css is certainly quicker and easier to learn.
- You can animate virutally any css property - colour, position, width, height, etc, etc
- You can produce a simple animation very quickly
- With the right CSS your animation can be very fast and fluid - very smooth
- CSS is not very flexibile as regards events and control structures - like loops etc
- It is hard to create complex structures - games etc. Possible, but hard.
- It has more events and control structures so it is easier to create more sophisticated code and longer control structures