CSS - Cascading Style Sheets

What is a CSS file

CSS refers to Cascading Style Sheets. It is a language used to specify the presentation of documents on a webpage. CSS data can be saved into a file, which then received the CSS file extension name. Coding within the document (HTML and other markup languages) are organized and formatted using CSS for presentation. Most web browsers use CSS to organize information and data. Elements within the text and document CSS stylizes include layout, color, font, images, and more. CSS allows improved content management, flexibility, and accessibility of the information on the webpage. Using CSS, various pages can have the same formatting and organization easily and allows different rending methods to be used.

CSS uses a simple syntax, using many English keywords to specify names for style properties. Selectors of CSS include: elements of specific types, elements specified by attribute (id or class), and elements depending on placement relative or nested within others in the document tree. Classes can contain various elements while ID’s tend to apply to a single instance of an element. Pseudo-classes for CSS selectors allow formatting based on outside information of the document tree. CSS also involves patterns (defining formatting for elements), declaration blocks, sources, specificity (relative weights and rules), inheritance, and whitespace.

Here's a small, but not exhaustive list of programs that can open CSS documents:

  • Mozilla Firefox
  • Internet Explorer
  • Google Chrome
  • Opera
Extension CSS
MIME type text/css
Useful links
Example Files
(703 bytes)