This is a really nice introduction to CSS transitions with interactive demos you can tinker with.
Maybe server-side-rendered HTML would actually be faster. Consider limiting the use of client-side frameworks to pages that absolutely require them.
Focusing on the median or average is the equivalent of walking around with a pair of blinders on. We’re limiting our perspective and, in the process, missing out on so much crucial detail. By definition, when we make improving the median or average our goal, we are focusing on optimizing for only about half of our sessions.
Tim does the numbers…
By honing in on the 90th—or 95th or similar—we ensure those weaknesses don’t get ignored. Our goal is to optimize the performance of our site for the majority of our users—not just a small subset of them.