CSS1 was published as a W3C Recommendation in 1996, with the final Recommendation dated 17 December 1996.
Cascading Style Sheets emerged from efforts to separate a document’s structure from its presentation. Håkon Wium Lie proposed Cascading HTML Style Sheets in 1994 while working at CERN with Tim Berners-Lee. Bert Bos’s work on style sheets also strongly influenced the final design, and he became CSS1’s co-author.
CSS1 introduced rules for fonts, colors, backgrounds, text spacing, alignment, margins, borders, padding, and basic positioning. Its “cascading” model allowed styles from different sources to combine, giving authors, users, and browsers distinct roles in presentation.
A common mix-up is confusing CSS1’s publication date with CSS2’s: CSS2 became a Recommendation in 1998. Another is treating 1994 as CSS1’s release year; that was the year Lie first proposed the language, not the year the W3C finalized its first Recommendation.