Things they should invent: "spoiler" HTML tags

Most of the time when someone wants to represent a spoiler, they do so either by typing "WARNING! SPOILERS AHEAD! LOOK OUT CAUTION!" then leaving about 16763 lines of spoiler space, or by making the text the same colour as the background so people have to highlight to read (which is of no help in text-only browsers).

The tag would be interpreted by most browsers as a quote box or code box containing text the same colour as the background, and would leave a screen's worth of spoiler space in text-only browsers. Maybe it could be construed in browsers for the blind as "The following contains spoilers. Do you want to proceed? (Y/N)" The specific attributes could be changed in the style sheets if desired.

I realize all this can already be done with existing HTML, but the spoiler tag would make it a bit easier for those who are not yet fluent in HTML.