CSS was first proposed in 1994, just as the Web was beginning to really catch on. In fact, the first draft of what would eventually become CSS (titled Cascading HTML Style Sheets) was published mere days before the first release of Mozilla (soon to be Netscape Navigator) was announced.
At the time, browsers gave all sorts of styling power to the user—the presentation preferences in Mosaic, for example, permitted all manner of font family, size, and color to be defined by the user on a per-element basis. None of this was available to document authors; all they could do was mark a piece of content as a paragraph, as a heading of some level, as preformatted text, or one of a handful of other element types. If a user configured his browser to make all level-one headings tiny and pink and all level-six headings huge and red, well, that was his lookout.
It was into this ...