Where value can be relative or absolute. If you use the a plus sign or a minus sign, then the size of the font is relative to the size of the base font, which defaults to 3. Heading <H1> corresponds to a font size of 6. Heading <H2> corresponds to a font size of 5, and so on. If you do not use a plus sign or a minus sign, then the font size is absolute. Font sizes range from 1 to 7.
I understand font sizes. What about colors?