Skip to Main Content
Cascading Style Sheets: The Definitive Guide, Second Edition
book

Cascading Style Sheets: The Definitive Guide, Second Edition

by Eric A. Meyer
March 2004
Intermediate to advanced content levelIntermediate to advanced
528 pages
16h 33m
English
O'Reilly Media, Inc.
Content preview from Cascading Style Sheets: The Definitive Guide, Second Edition

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.

Numbers

There are two types of numbers in CSS: integers (“whole” numbers) and reals (fractional numbers). These number types serve primarily as the basis for other value types, but, in a few instances, raw numbers can be used as a value for a property.

In CSS2.1, a real number is defined to be an integer that is optionally followed by a decimal and fractional numbers. Therefore, the following are all valid number values: 15.5, -270.00004, and 5. Both integers and reals may be either positive or negative, although properties can (and often do) restrict the range of numbers they will accept.

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Start your free trial

You might also like

Cascading Style Sheets: The Definitive Guide

Cascading Style Sheets: The Definitive Guide

Eric A. Meyer

Publisher Resources

ISBN: 0596005253Catalog PageErrata