Style sheet (web development)
| Cascading Style Sheets |
|---|
| Concepts |
| Philosophies |
| Tools |
| Comparisons |
| HTML |
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| HTML and variants |
| HTML elements and attributes |
| Editing |
| Character encodings and language |
| Document and browser models |
| Client-side scripting and APIs |
| Graphics and Web3D technology |
| Comparisons |
A web style sheet is a form of separation of content and presentation for web design in which the markup (i.e., HTML or XHTML) of a webpage contains the page's semantic content and structure, but does not define its visual layout (style). Instead, the style is defined in an external style sheet file using a style sheet language such as CSS or XSLT. This design approach is identified as a "separation" because it largely supersedes the antecedent methodology in which a page's markup defined both style and structure.
The philosophy underlying this methodology is a specific case of separation of concerns.