Prince supports RGB, RGBA, CMYK, and named spot colors.
RGB
RGB colors can be specified using the rgb()
function syntax,
shorthand hash notation, or with standard keywords. For example, red can be
specified in three ways:
color: rgb(255, 0, 0) color: #ff0000 color: red
RGBA
RGBA colors are equivalent to RGB plus an opacity (or alpha) value between 0 and 1. When the opacity is 0 the color is transparent, and when the opacity is 1 the color is identical to the RGB color.
color: rgba(255, 0, 0, 1) // red color: rgba(255, 0, 0, 0.5) // translucent red color: rgba(255, 0, 0, 0) // fully transparent
CMYK
CMYK colors can be specified using the cmyk()
function syntax:
color: cmyk(1, 0, 0, 0) // cyan color: cmyk(0, 1, 1, 0) // red color: cmyk(0, 0, 0, 1) // black
Spot colors
Named spot colors can be defined using the @prince-color
rule.
An alternate RGB or CMYK color must also be specified using the
alternate-color
property. This will be used in situations where
the named color is not available, such as when viewing the generated PDF file
on a display.
@prince-color MyColor { alternate-color: rgb(255,0,0) }
Spot colors can be used with a specified tint value between 0 and 1, which defaults to 1. They can also enable overprint:
color: prince-color(MyColor) // tint 1.0 color: prince-color(MyColor, 0.5) // tint 0.5 color: prince-color(MyColor, overprint) // tint 1.0, overprint color: prince-color(MyColor, 0.5, overprint) // tint 0.5, overprint