This lesson is part of a series on computer programming. You can go to Intro to Programming if you'd like to start at the beginning.
Once you've completed this tutorial, you should have all the tools you need to write CSS for your webpages.
However, if you want learn more about CSS properties that we didn't cover, explore more advanced concepts, or find answers to any specific questions you might have, try some of the external resources below. Keep in mind that these resources aim to cover everything, so don't be overwhelmed by the scale. No programmer, no matter how experienced or talented, is expected to memorize all of what you see.
MDN Web Docs is a resource created by Mozilla, the company that manages the Firefox web browser. It provides a huge selection of tutorials and resources for every part of web development. Most of it will not be relevant to you yet, but they either provide or endorse a number of resources you may find useful.
w3schools is a resource aimed at web developers that covers just about every CSS concept or element one might come across. Most concepts include brief explanations and demos. Given the quantity of concepts, though, you will probably find it most useful as reference, similar to the MDN Web Docs resources above.
Stack Overflow is a question-and-answer platform that allows programmers to ask questions, which other programmers then answer. It is used regularly by programmers of every experience level, so it can be intimidating at first, but it can be invaluable when you run into problems or get stuck.
Anybody can ask questions on Stack Overflow, but for beginners, it's most useful as a record of questions others have already asked. Almost any problem you experience or concept you find confusing early on has already had a question asked about it. If you have trouble with anything, after all, you can rest assured that you are not the only one.