CSS1

CSS1 stands for Cascading Style Sheets Level 1, the first formal standard for CSS. It was developed by the World Wide Web Consortium (W3C) CSS Working Group and involved contributors such as Håkon Wium Lie and Bert Bos. It was published as a W3C Recommendation in December 1996. The specification defined a language for describing how HTML documents are presented, enabling authors to separate content from presentation and to apply consistent styling across pages.

CSS1 introduced the core concepts of the cascade and inheritance, along with a basic selector system and a box model. Authors could target elements with type selectors, class selectors, and ID selectors, and combine them using descendant relationships. The box model established that every element is a rectangular box with margins, borders, padding, and content, with properties to control width, height, and spacing. The property set covered typography (font, color), backgrounds, borders, margins and padding, lists, tables, and basic layout and display controls such as display, float, and positioning.

Limitations of CSS1 included a limited property set and relatively weak cross-browser consistency in the late 1990s. It did not support advanced layout features, complex selectors, or media-specific rules that would appear in later CSS specifications. Nonetheless, CSS1 established the foundational concepts and syntax that underpinned subsequent standards such as CSS2 and CSS3 and contributed to the broader adoption of separation of content and presentation on the Web.