Over the past few years, we’ve seen front end development go through some significant changes in how we approach pretty much everything. Whether it be height/width, font sizes, icons, responsive - the way we set these values up on the front end has changed, and so too must our designers in order for our two worlds to truly start working in harmony.
I recently had a chance to take a look at the Laravel framekwork and its IoC (inversion of control) container. If you're already familiar with D8 then this should be a walk in the park. If not, then I think this should be a good stepping stone on your way to D8.