Board Thread:Support Requests - Designing Your Wiki/@comment-5029965-20170502073248/@comment-5811199-20170502083632

Hey, this is a perfectly fine place to ask this question :)

If you mean a parallax effect as in the background moving slightly slower than scroll, yes that should be fine. You should take a look at the Help:Customization policy page to see what sort of customisation is and isn't allowed.

If you're still unsure, you're free to send a message to Staff using Special:Contact/general and ask for specifics or ask about something you've coded up. They can give you exact yes/no answers on what you want to change.