Or, when something doesn’t work, you know why it didn’t work and can quickly fix it without having to ask someone or do a Google search.

It isn’t about learning all of the properties of CSS — which is what most tutorials and courses do, they say “here is a bunch of different things you can do with CSS” — but learn how CSS itself works.

People learn about things like the cascade and specificity, but they don't really understand how they work.

Then there are the things that people often have never heard of, such as formatting contexts and stacking context.

Could you explain to someone else how these work?

Have you even heard of them?

The overlooked fundamentals
People have heard of these fundamental concepts, but often ignore them because they seem relatively simple. A lot of people feel that they know them really well, but this is one of the places where many people, from beginners to experienced developers make mistakes. 

This section of the course covers:

The unknown fundamentals
These are literally the most fundamental concepts of CSS, the things that dictate how the page is rendered, and yet most people have never even heard of them.

Stop wasting your time hoping that your CSS is going to work and start txruly understanding the fundamentals that will step your game up to the next level.

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