Chapter 4. Values and Units

In this chapter, we'll tackle the elements that are the basis for almost everything you can do with CSS: the units that affect the colors, distances, and sizes of a whole host of properties. Without units, you couldn't declare that a paragraph should be purple, or that an image should have 10 pixels of blank space around it, or that a heading's text should be a certain size. By understanding the concepts put forth here, you'll be able to learn and use the rest of CSS much more quickly.