In CSS, the style markup that goes with HTML, colors are encoded as hexadecimal RGB values of either 3 or 6 letters. This means that certain words, such as EFFACE and FACADE, are legitimate CSS colors. Allow for substitutions, such as 0 for O, and a full gamut presents itself, with BIOTIC and OTITIS and so on. c0ffee.surge.sh is a beautiful collection of all the words that work.