Boot Camp

Styling Code, Part 1
15
Styling Code, Part 1
So far, we’ve been looking at elements, values, and attributes, and sticking with rudimentary
style information. Now we are going to look into the basics of Cascading Styles
(CS). It’s usually referred to as CSS, but technically CSS stands for Cascading Style
Sheets, and if you are not linking external style sheets to your web pages, you aren’t using
CSS. Just the Cascading Styles part of the benefit.
CS is a style language used to describe the presentation semantics (the look and formatting)
of a document written in a markup language – HTML, XHTML, and XML. It is
designed primarily to enable the separation of document content (written in HTML or a
similar markup language) from document presentation, including elements such as the
layout, colors, and fonts. This separation can improve content accessibility, provide more
flexibility and control in the specification of presentation characteristics, and reduce complexity
and repetition in the structural content (such as by allowing for table-less web design).
It is called ‘Cascading’ in reference to Cascading Style Sheets (CSS), where one change
made in a style sheet file can cascade changes in the appearance of that style in all the
web pages linked to it. Also, CSS specifies a priority scheme to determine which style
rules apply if more than one rule matches against a particular element. In this so-called
cascade, priorities or weights are calculated and assigned to rules, so that the results are
predictable.
Cascading styling specifications are different than those used with HTML style attributes
and values (most of which are now deprecated). These specifications are exacting for CS
to work.
You can associate formatting instructions with a web page by defining CS rules in either
an embedded, linked, or inline style sheet. Although there are many ways of defining
styles, the main difference between them is where they are located. CS can be coded in
three ways:
• Inline style rules: Cascading styling is coded inline right in the HTML tags of
web pages.
• Embedded head section style rules: Cascading styling for items used repetitive-
145