CSS, short for Cascading Style Sheets, are rules (or “styles”) that define how content should look on a web page. To give you an example, if your web page contains a table, you can use CSS to specify the thickness of the border and the color of text inside that table.
Learning CSS is easy. There are a plethora of good online tutorials or, if you prefer the traditional route, get a book. My favorites CSS books include HTML & CSS by John Duckett and CSS Secrets by Lea Verou.
I recently stumbled upon a couple of web resources that take the help of cats and post-it notes and make learning CSS even more interesting and entertaining.
CSS Basics with Post-It Notes (link)
Designer Kaylan takes the help of colorful post-it notes for visualizing the the basic concepts of CSS.
CSS Selectors Explained with CSS (link)
If you have figured out how to write selectors in CSS, half the battle is one. Mike Borsare uses #cats to help you learn the basic CSS selector syntax.
CSS Dinner Table (link)
If you know the basic of CSS selectors, use the Dinner table to practice your CSS skills. Here you have plates and fruits placed on a dinner table and your task is to select the various elements using selectors.
Related: Learn to Code Online