Stylesheet rules

Here is an example of a simple style sheet rule:

H1 { color: green }

This is a simple style sheet that contains one rule. A rule is a statement about one stylistic aspect of one or more elements. A style sheet is a set of one or more rules that applies to an HTML document. This rule sets the color of all first-level headings (H1).

A rule consists of two parts:

•The selector is the part before the left curly brace. This is the link between the HTML document and the style. The selector specifies what elements are affected by the declaration. In the example, the selector is H1.

•One or more declarations. A declaration states a rule. It sets a property of the element(s) designated by the selector(s) to a value.

Selectors can be grouped in comma-separated lists:

H1,H2,H3 { color: green }

H1, H2, H3 {...}

As the example shows, each declaration has two parts separated by a colon:

property : value

Between the curly braces, you can have multiple declarations separated by semicolons.