Basic Syntax: Contextual Selectors
Contextual selectors are merely strings of two or more simple selectors separated
by white space. These selectors can be assigned normal properties and, due
to the rules of cascading order, they will take precedence over simple selectors.
For example, the contextual selector in
| P EM { background: yellow } |
is P EM . This rule says that emphasized text within a paragraph should have a yellow background; emphasized text in a heading would be unaffected.
Properties
A property is assigned to a selector in order to manipulate
its style. Examples of properties include color , margin ,
and font .
Values
The declaration value is an assignment that a property receives.
For example, the property color could receive the value red .
Grouping
In order to decrease repetitious statements within style sheets, grouping of
selectors and declarations is allowed. For example, all of the headings in
a document could be given identical declarations through a grouping:
| H1, H2, H3, H4, H5, H6 { color: red; font-family: sans-serif } |
Inheritance
Virtually all selectors which are nested within selectors will inherit the
property values assigned to the outer selector unless otherwise modified.
For example, a color defined for the BODY will
also be applied to text in a paragraph.
There are some cases where the inner selector does not inherit the surrounding selector's values, but these should stand out logically. For example, the margin-top property is not inherited; intuitively, a paragraph would not have the same top margin as the document body.
Comments
Comments are denoted within style sheets with the same conventions that are
used in C programming. A sample CSS1 comment would be in the format:
More HTML and CSS: 
