Another don't call it a reset from Sindre Sorhus. It's a port of Normalize that, as the name suggests, is modernized to remove some of the older stuff and add a few opinionated bits. I'm good with light sensible opinions, like in this case,
box-sizing: border-box; everywhere. This looks similar to sanitize.css which is also based on Normalize and brings a few more sensible opinions. Same with Reboot.
If you're interested in some of the history and thinking behind these things, I wrote about that not long ago. Daniel Box made a little tool to compare them and I forked it to include modern-normalize.