Greasy Fork镜像

performance improvements

Completely refactored code for less memory usage
Still a WIP so there are bugs, but it's a lot nicer to your phone battery now.

Changed method of creating the timer so it appears immediately upon page load
Changed mutationObserver to more consistently keep track of the actual time remaining
Changed the timer to go by milliseconds instead of seconds for a smoother appearance, because I like making things look nice for no real reason