1. CSS Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation semantics (that is, the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can also be applied to any kind of XML document, including SVG and XUL.

2. HISTORY Style sheets have existed in one form or another since the beginnings of SGML in the 1970s. Cascading Style Sheets were developed as a means for creating a consistent approach to providing style information for web documents. As HTML grew, it came to encompass a wider variety of stylistic capabilities to meet the demands of web developers. This evolution gave the designer more control over site appearance but at the cost of HTML becoming more complex to write and maintain. Variations in web browser implementations made consistent site appearance difficult, and users had less control over how web content was displayed.

3. CSS STYLING

7. CSS BOX MODEL

14. CSS GROUPING AND NESTING SELECTORS

17. CSS DISPLAY

19. CSS POSITIONING

21. Static Positioning HTML elements are positioned static by default. A static positioned element is always positioned according to the normal flow of the page. Static positioned elements are not affected by the top, bottom, left, and right properties.

23. CSS NAVIGATION BAR

25. Horizontal Navigation Bar Horizontal Navigation Bar There are two ways to create a horizontal navigation bar. Using inline or floating list items. Both methods work fine, but if you want the links to be the same size, you have to use the floating method.

30. CSS FLOAT PROPERTIES Property Description Values CSS clear Specifies which sides of an element where other floating elements are not allowed left right both none inherit 1 float Specifies whether or not a box should float left right none inherit 1