CSS Introduction

What is CSS? Cascading Style Sheets (CSS) is a simple mechanism for adding style (e.g., fonts, colors, spacing) to Web documents.

哈肯·萊於1994年在芝加哥的一次會議上第一次展示了CSS的建議，1995年他與波斯一起再次展示這個建議。當時W3C剛剛建立，W3C對CSS的發展很感興趣，它為此組織了一次討論會。

CSS is used to define styles for your web pages, including the design, layout and variations in display for different devices and screen sizes.

Well organized and easy to understand Web building tutorials with lots of examples of how to use HTML, CSS, JavaScript, SQL, PHP, Python, Bootstrap, ...

In CSS, selectors are patterns used to select the element(s) you want to style. Use our CSS Selector Tester to demonstrate the different selectors.

CSS is the language we use to style an HTML document. CSS describes how HTML elements should be displayed. This tutorial will teach you CSS from basic to ...

CSS 是一种描述HTML 文档样式的语言。 CSS 描述应该如何显示HTML 元素。 本教程将从零起点的基础教程开始，一直到CSS3 高级教程，为您提供全面系统地讲解。

Note: If you want to validate your CSS style sheet embedded in an (X)HTML document, you should first check that the (X)HTML you use is valid.

W3.CSS is a modern, responsive, mobile first CSS framework. W3.CSS provides equality for all browsers: Chrome. Firefox. Edge. IE. Safari. Opera.

This is the official CSSWG repository for editor's drafts of CSS specifications. See the contributor guidelines for how to contribute.