### Problem https://design.gitlab.com/foundations/motion is currently lacking in terms of documentation and guidance for choosing the correct easing curves for animations. ### Proposal https://vimeo.com/282452432 at ± `26:00` states that using [custom easing css curves](https://gist.github.com/bendc/ac03faac0bf2aee25b49e5fd260a727d) can have a big impact on the user experience when used well. #### Additional sources Improve documentation with information from: * https://www.nngroup.com/articles/animation-usability/ * https://www.nngroup.com/articles/progress-indicators/ * https://spectrum.adobe.com/page/motion/