I would've liked to see the ">" (element-element selector, .foo > .bar) and explanation of a space (e.g., .foo.bar vs .foo .bar). These above examples are quit

I would've liked to see the ">" (element-element selector, .foo > .bar) and explanation of a space (e.g., .foo.bar vs .foo .bar). These above examples are quite common in real-world CSS, and the nuances in syntax are small, yet they have a big impact on document styling.