CSS Units

From http://www.w3schools.com (Copyright Refsnes Data)

# CSS Units

### Measurements

Unit | Description
--- | ---
% | percentage
in | inch
cm | centimeter
mm | millimeter
em | 1em is equal to the current font size. 2em means 2 times the size of the current font. E.g., if an element is displayed with a font of 12 pt, then '2em' is 24 pt. The 'em' is a very useful unit in CSS, since it can adapt automatically to the font that the reader uses
ex | one ex is the x-height of a font (x-height is usually about half the font-size)
pt | point (1 pt is the same as 1/72 inch)
pc | pica (1 pc is the same as 12 points)
px | pixels (a dot on the computer screen)

### Colors

Unit | Description
--- | ---
color_name | A color name (e.g. red)
rgb(x,x,x) | An RGB value (e.g. rgb(255,0,0))
rgb(x%, x%, x%) | An RGB percentage value (e.g. rgb(100%,0%,0%))
#rrggbb | A HEX number (e.g. #ff0000)

From http://www.w3schools.com (Copyright Refsnes Data)