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CSS developer guide

Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in HTML or other markup languages such as Scalable Vector Graphics (SVG). CSS describes how the structured elements in the document are to be rendered on screen, on paper, in speech, or on other media. The ability to adjust the document's presentation depending on the output medium is a key feature of CSS.

CSS is one of the core languages of the open Web and has a standardized W3C specification.

Documentation

Block formatting context
A block formatting context is a part of a visual CSS rendering of a Web page. It is the region in which the layout of block boxes occurs and in which floats interact with each other.
Getting started with CSS
This tutorial introduces you to the basic features and language (the syntax) for Cascading Style Sheets (CSS). You use CSS to change the look of a structured document, such as a web page. The tutorial also includes sample exercises you can try on your own computer to see the effects of CSS and features that work in modern browsers.
Underscores in class and ID Names
Summary: The use of the underscore character in CSS can lead to major display problems in multiple browsers. Learn why this is so, and how to keep your sites from being bitten by this problem. This technical note examines the use of underscores in CSS, and why they should be generally avoided in most circumstances.

These topics may also be of interest:

Visual formatting model
The CSS visual formatting model is an algorithm that processes a document and displays it on visual media.
Writing efficient CSS
This document provides guidelines for optimizing CSS code, and more specifically on how to write efficient selectors.

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 Contributors to this page: riteshgaur, fscholz, Zunaith, Mads, jswisher, Sheppy
 Last updated by: riteshgaur,