CSS Units Reference Guide

Unit Description
Measurements
% percentage
in inch
cm centimeter
mm millimeter
em one em is equal to the current font size of the current element
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
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)
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