It can be learned, by the same techniques you use to learn system internals: You can first do a quick scout for the big items (e.g. grid systems, typography ins

It can be learned, by the same techniques you use to learn system internals: You can first do a quick scout for the big items (e.g. grid systems, typography instead of data structures, algorithms) so that you get the big picture, and then study designs that you like for the details of how they used these items together (like how you study frameworks, libraries or OSs)