Check out example codes for "history of css". It will help you in understanding the concepts better.
Code Example 1
/* Answer to: "history of css" */ /* The saga of CSS starts in 1994. Håkon Wium Lie works at CERN – the cradle of the Web – and the Web is starting to be used as a platform for electronic publishing. One crucial part of a publishing platform is missing, however: There is no way to style documents. For example, there is no way to describe a newspaper-like layout in a Web page. Having worked on personalized newspaper presentations at the MIT Media Laboratory, Håkon saw the need for a style sheet language for the Web. Style sheets in browsers were not an entirely a new idea... To read the rest of the History of CSS, go check out: https://www.w3.org/Style/CSS20/history.html */
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