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Chapter 13: Inserting and Formatting Text
A CSS formatting rule consists of two parts—the selector and the declaration. The selector is
a term (such as
a term (such as
P
,
H1
,
a class name, or an id) that identifies the formatted element, and the
declaration defines what the style elements are. In the following example,
H1
is the selector,
and everything that falls between the braces (
{}
) is the declaration:
H1 {
font-size: 16 pixels;
font-family: Helvetica;
font-weight:bold;
font-family: Helvetica;
font-weight:bold;
}
The declaration consists of two parts, the property (such as
font-family
) and value (such as
Helvetica
). In the previous CSS rule a particular style has been created for
H1
tags: the text
for all
H1
tags linked to this style will be 16 pixels in size, Helvetica font, and bold.
The term cascading refers to your ability to apply multiple styles to the same element. For
example, you can create one CSS rule to apply color and another to apply margins, and apply
them both to the same text on a page. The defined styles “cascade” down to the elements on
your web page, ultimately creating the design you want.
example, you can create one CSS rule to apply color and another to apply margins, and apply
them both to the same text on a page. The defined styles “cascade” down to the elements on
your web page, ultimately creating the design you want.
A major advantage of CSS is that it provides easy update capability; when you update a CSS
rule in one place, the formatting of all the documents that use the defined style are
automatically updated to the new style.
rule in one place, the formatting of all the documents that use the defined style are
automatically updated to the new style.
You can define the following types of styles in Dreamweaver:
■
Custom CSS rules, also called class styles, let you apply style attributes to any range or
block of text. (See
block of text. (See
.)
■
HTML tag styles redefine the formatting for a particular tag, such as
h1
. When you create
or change a CSS style for the
h1
tag, all text formatted with the
h1
tag is immediately
updated.
■
CSS selector styles (advanced styles) redefine the formatting for a particular combination
of elements, or for other selector forms as allowed by CSS (for example, the selector
of elements, or for other selector forms as allowed by CSS (for example, the selector
td h2
applies whenever an
h2
header appears inside a table cell.) Advanced styles can also
redefine the formatting for tags that contain a specific
id
attribute (for example, the styles
defined by
#myStyle
apply to all tags that contain the attribute-value pair
id="myStyle"
).
CSS rules can reside in the following locations:
External CSS style
sheets
are collections of CSS rules stored in a separate, external CSS
(.css) file (not an HTML file). This file is linked to one or more pages in a website using a link
in the head section of a document.
in the head section of a document.
Internal (or embedded) CSS style sheets
are collections of CSS rules included in a
style
tag in the head portion of an HTML document.