Chapter 3. Understanding Cascading Style Sheets

In the previous chapter, you learned the basics of HTML and XHTML, including how to set up a skeletal HTML template for all your web content. In this chapter, you will learn how to fine-tune the display of your web content using Cascading Style Sheets (CSS).

The concept behind style sheets is simple: You create a style sheet document that specifies the fonts, colors, spacing, and other characteristics that establish a unique look for a website. You then link every page that should have that look to the style sheet, instead of specifying all those styles repeatedly in each separate document. Therefore, when you decide to change your official corporate typeface or color scheme, you can modify all your web pages at once just by changing one or two entries in your style sheet rather than changing them in all of your static web files. So, a style sheet is a grouping of formatting instructions that controls the appearance of several HTML pages at once.

Style sheets enable you to set a great number of formatting characteristics, including exacting typeface controls, letter and line spacing, and margins and page borders, just to name a few. Style sheets also enable sizes and other measurements to be specified in familiar units, such as inches, millimeters, points, and picas. You can also use style sheets to precisely position graphics and text anywhere on a web page, either at specific coordinates or relative to other items on the page.

In short, style sheets bring a sophisticated level of display to the Web. And they do so—you’ll pardon the expression—with style.