One of the best ways to learn is by looking at other code, and CSS3 Generator can write custom CSS code for you so you can learn how it works (or just use it).

How to Customize CSS in Blogspot. The Blogger Template Designer allows you to insert custom CSS code to change your blog's appearance. You can access the advanced settings of the Template Designer ...

Learn how to build a custom CSS framework for flexible, scalable, and efficient web design. Ditch bloated frameworks and take control today!

Click "Advanced" in the designer's first column, then click "Add CSS," the last link in the second column. Paste the following code into the "Add Custom CSS" box: ...

Microsoft has announced that CSS Custom Properties will making their way to its Edge browser in the Windows 10 Creators Update, unlocking "potential for more creative work on the web".