There are a lot of "gotchas" with CSS. The only thing I used books for was to read about how other people organized their stylesheets. Other than that, doing it

There are a lot of "gotchas" with CSS. The only thing I used books for was to read about how other people organized their stylesheets. Other than that, doing it day in and day out for years was how I ended up learning. People will design all sorts of stuff that requires some creative problem solving with the tools CSS gives you. If I see something interesting on a site, I'll open inspector and see how they did it. That's usually how I learn new tricks. That and by experimenting on my own. As far as not having to use trial and error, that just takes practice. I'll go for 3 years making sites that all look the same, then tastes change and I have to go through trial and error again figuring out the best way to do something new until I've done it so many times I don't even need to look at the screen when coding anymore.