13 - CSS Introduction
CSS comes from Cascade Style Sheets. It is the language used to
format web pages (text, background or layout, etc.).
In other words, HTML structures a document, while CSS formats it.
CSS can be applied to single HTML elements, or it can be kept in a separate
file and applied to elements throughout a document. Files that hold CSS are
called “style sheets” and use the .css extension. Unlike HTML, CSS uses
rules instead of tags.
CSS code can be written in three ways: inline, internal, external.
1. Inline - directly into the HTML tag