Help Imperative -> Functional

Hello all, I am learning about functional programming style with Javascript and as an exercise I am trying to convert a function that is written in a more imperative style, to a more functional approach. I have a pretty good understanding of the concepts (currying, partial application, fn purity, side-effect minimization), however i am having a tough time applying them. I know I should be taking in more values as inputs instead of using vals outside the functions scope, as I said just having a hard time seeing how to do this and make them more composable. The animation function in particular calls ease with vals generated outside its scope. I know this is not advisable in the functional world. Been at it for hours with little progress, so any help would be hugely appreciated. https://codepen.io/marti2221/pen/LaZymE?editors=0010

Would need to see the code

sorry, it is now updated with a link