What would you recommend as a learning resource? If you had a week, and wanted to dig in and learn CSS in the way you describe, what would your ideal curriculum look like?
A static website I think is a good way. The most important part is layout. Once you master flex and css selectors, everything else is a derivative one way or another.
It's probably not a good idea to focus an entire week on CSS alone. It's more economical and practical to spend a week's worth of hours in an otherwise broader project. That gives you real, practical experience in building real-world UI.
I agree with Achshar's post. I'd also recommend using caniuse.com to get a better understanding of what is and isn't supported in the various browsers.
It's probably not a good idea to focus an entire week on CSS alone. It's more economical and practical to spend a week's worth of hours in an otherwise broader project. That gives you real, practical experience in building real-world UI.