Appendix C. Cascading Style Sheet Properties Quick Reference

In the following table, we list, in alphabetical order, all the properties defined in the World Wide Web Consortium’s (W3C’s) Recommended Specification for Cascading Style Sheets (CSS), Level 2 ( We include each property’s possible values, defined as either an explicit keyword (shown in constant width) or as one of these values:


A numeric value followed by deg, grad, or rad.


Either a color name or hexadecimal RGB value, as defined in Appendix G, or an RGB triple of the form:

rgb(red, green, blue)

where red, green, and blue are either numbers in the range 0 to 255 or percentage values indicating the brightness of that color component. Values of 255 or 100% indicate that the corresponding color component is at its brightest; values of 0 or 0% indicate that the corresponding color component is turned off completely. For example:

rgb(27, 119, 207)
rgb(50%, 75%, 0%)

are both valid color specifications.


A numeric value followed by hz or khz, indicating hertz or kilohertz.


An optional sign (either + or -), immediately followed by a number (with or without a decimal point), immediately followed by a two-character unit identifier. For values of 0, the unit identifier may be omitted.

The unit identifiers em and ex refer to the overall height of the font and to the height of the letter “x,” respectively. The unit identifier px is equal to a single pixel on the display device. ...

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