I asked a member of the engineering team, “How is progress calculated?”

“Oh, it’s complete nonsense,” they replied with a chuckle.

The progress bar filled every few seconds, regardless of actual progress… Once the operation actually finished, progress jumped from wherever it happened to be to 100%…

I was young, naive, and a little appalled by this explanation. “You’re lying to the user?” I thought.

Arguments?! Return values?! What's crazier, you can use functions right now in Chrome Canary! So, after reading and playing around, here are my key insights on what you need to know about CSS Functions.

I've already written about how the fact that the initial value of a custom property is a guaranteed-invalid value can lead to unexpected results. Today, I realized how that can be problematic when you use custom properties in shorthand properties.

A handy glossary of terms used when discussing design tokens and design systems.

Learn how the Cache-Control request header works, how browsers handle refresh and hard refresh caching, and when developers should use it for realtime data and offline-first applications.