Colors
- Dart Sass
- since 1.79.0
- LibSass
- ✗
- Ruby Sass
- ✗
LibSass, Ruby Sass, and older versions of Dart Sass don’t support color spaces
other than rgb
and hsl
.
As well as to adding support for new color spaces, this release changed some
details of the way colors were handled. In particular, even the legacy rgb
and hsl
color spaces are no longer clamped to their gamuts; it’s now
possible to represent rgb(500 0 0)
or other out-of-bounds values. In
addition, rgb
colors are no longer rounded to the nearest integer because
the CSS spec now requires implementations to maintain precision wherever possible.
- Dart Sass
- since 1.14.0
- LibSass
- ✗
- Ruby Sass
- since 3.6.0
LibSass and older versions of Dart or Ruby Sass don’t support hex colors with an alpha channel.
Sass has built-in support for color values. Just like CSS colors, each color
represents a point in a particular color space such as rgb
or lab
. Sass
colors can be written as hex codes (#f2ece4
or #b37399aa
), CSS color names
(midnightblue
, transparent
), or color functions like rgb()
, lab()
,
or color()
.
SCSS Syntax
@debug #f2ece4; // #f2ece4
@debug #b37399aa; // rgba(179, 115, 153, 67%)
@debug midnightblue; // #191970
@debug rgb(204 102 153); // #c69
@debug lab(32.4% 38.4 -47.7 / 0.7); // lab(32.4% 38.4 -47.7 / 0.7)
@debug color(display-p3 0.597 0.732 0.576); // color(display-p3 0.597 0.732 0.576)
Sass Syntax
@debug #f2ece4 // #f2ece4
@debug #b37399aa // rgba(179, 115, 153, 67%)
@debug midnightblue // #191970
@debug rgb(204 102 153) // #c69
@debug lab(32.4% 38.4 -47.7 / 0.7) // lab(32.4% 38.4 -47.7 / 0.7)
@debug color(display-p3 0.597 0.732 0.576) // color(display-p3 0.597 0.732 0.576)
Color SpacesColor Spaces permalink
Sass supports the same set of color spaces as CSS. A Sass color will always be
emitted in the same color space it was written in unless it’s in a legacy color
space or you convert it to another space using color.to-space()
. All the
other color functions in Sass will always return a color in the same spaces as
the original color, even if the function made changes to that color in another space.
Although each color space has bounds on the gamut it expects for its channels, Sass can represent out-of-gamut values for any color space. This allows a color from a wide-gamut space to be safely converted into and back out of a narrow-gamut space without losing information.
⚠️ Heads up!
CSS requires that some color functions clip their input channels. For example,
rgb(500 0 0)
clips its red channel to be within [0, 255] and so is
equivalent to rgb(255 0 0)
even though rgb(500 0 0)
is a distinct value
that Sass can represent. You can always use Sass’s color.change()
function
to set an out-of-gamut value for any space.
Following is a full list of all the color spaces Sass supports. You can read learn about these spaces on MDN.
Space | Syntax | Channels [min, max] |
---|---|---|
rgb * |
rgb(102 51 153) #663399 rebeccapurple
|
red [0, 255]; green [0, 255]; blue [0, 255] |
hsl * |
hsl(270 50% 40%) |
hue [0, 360]; saturation [0%, 100%]; lightness [0%, 100%] |
hwb * |
hwb(270 20% 40%) |
hue [0, 360]; whiteness [0%, 100%]; blackness [0%, 100%] |
srgb |
color(srgb 0.4 0.2 0.6) |
red [0, 1]; green [0, 1]; blue [0, 1] |
srgb-linear |
color(srgb-linear 0.133 0.033 0.319) |
red [0, 1]; green [0, 1]; blue [0, 1] |
display-p3 |
color(display-p3 0.374 0.21 0.579) |
red [0, 1]; green [0, 1]; blue [0, 1] |
a98-rgb |
color(a98-rgb 0.358 0.212 0.584) |
red [0, 1]; green [0, 1]; blue [0, 1] |
prophoto-rgb |
color(prophoto-rgb 0.316 0.191 0.495) |
red [0, 1]; green [0, 1]; blue [0, 1] |
rec2020 |
color(rec2020 0.305 0.168 0.531) |
red [0, 1]; green [0, 1]; blue [0, 1] |
xyz , xyz-d65 |
color(xyz 0.124 0.075 0.309) color(xyz-d65 0.124 0.075 0.309)
|
x [0, 1]; y [0, 1]; z [0, 1] |
xyz-d50 |
color(xyz-d50 0.116 0.073 0.233) |
x [0, 1]; y [0, 1]; z [0, 1] |
lab |
lab(32.4% 38.4 -47.7) |
lightness [0%, 100%]; a [-125, 125]; b [-125, 125] |
lch |
lch(32.4% 61.2 308.9deg) |
lightness [0%, 100%]; chroma [0, 150]; hue [0deg, 360deg] |
oklab |
oklab(44% 0.088 -0.134) |
lightness [0%, 100%]; a [-0.4, 0.4]; b [-0.4, 0.4] |
oklch |
oklch(44% 0.16 303.4deg) |
lightness [0%, 100%]; chroma [0, 0.4]; hue [0deg, 360deg] |
Spaces marked with * are legacy color spaces.
Missing ChannelsMissing Channels permalink
Colors in CSS and Sass can have "missing channels", which are written none
and
represent a channel whose value isn’t known or doesn’t affect the way the color
is rendered. For example, you might write hsl(none 0% 50%)
, because the hue
doesn’t matter if the saturation is 0%
. In most cases, missing channels are
just treated as 0 values, but they do come up occasionally:
-
If you’re mixing colors together, either as part of CSS interpolation for something like an animation or using Sass’s
color.mix()
function, missing channels always take on the other color’s value for that channel if possible. -
If you convert a color with a missing channel to another space that has an analogous channel, that channel will be set to
none
after the conversion is complete.
Although color.channel()
will return 0 for missing channels, you can always
check for them using color.is-missing()
.
SCSS Syntax
@use 'sass:color';
$grey: hsl(none 0% 50%);
@debug color.mix($grey, blue, $method: hsl); // hsl(240, 50%, 50%)
@debug color.to-space($grey, lch); // lch(53.3889647411% 0 none)
Sass Syntax
@use 'sass:color'
$grey: hsl(none 0% 50%)
@debug color.mix($grey, blue, $method: hsl) // hsl(240, 50%, 50%)
@debug color.to-space($grey, lch) // lch(53.3889647411% 0 none)
Powerless ChannelsPowerless Channels permalink
A color channel is considered "powerless" under certain circumstances its value
doesn’t affect the way the color is rendered on screen. The CSS spec requires
that when a color is converted to a new space, any powerless channels are
replaced by none
. Sass does this in all cases except conversions to legacy
spaces, to guarantee that converting to a legacy space always produces a color
that’s compatible with older browsers.
For more details on powerless channels, see color.is-powerless()
.
Legacy Color SpacesLegacy Color Spaces permalink
Historically, CSS and Sass only supported the standard RGB gamut, and only
supported the rgb
, hsl
, and hwb
functions for defining colors. Because at
the time all colors used the same gamut, every color function worked with every
color regardless of its color space. Sass still preserves this behavior, but
only for older functions and only for colors in these three "legacy" color
spaces. Even so, it’s still a good practice to explicitly specify the $space
you want to work in when using color functions.
Sass will also freely convert between different legacy color spaces when converting legacy color values to CSS. This is always safe, because they all use the same underlying color model, and this helps ensure that Sass emits colors in as compatible a format as possible.
Color FunctionsColor Functions permalink
Sass supports many useful color functions that can be used to create new
colors based on existing ones by mixing colors together or scaling their
channel values. When calling color functions, color spaces should always be
written as unquoted strings to match CSS, while channel names should be written
as quoted strings so that channels like "red"
aren’t parsed as color values.
💡 Fun fact:
Sass color functions can automatically convert colors between spaces, which
makes it easy to do transformations in perceptually-uniform color spaces like
Oklch. But they’ll always return a color in the same space you gave it,
unless you explicitly call color.to-space()
to convert it.
SCSS Syntax
@use 'sass:color';
$venus: #998099;
@debug color.scale($venus, $lightness: +15%, $space: oklch);
// rgb(170.1523703626, 144.612080603, 170.1172627174)
@debug color.mix($venus, midnightblue, $method: oklch);
// rgb(95.9363315581, 74.5687109346, 133.2082569526)
Sass Syntax
@use 'sass:color'
$venus: #998099
@debug color.scale($venus, $lightness: +15%, $space: oklch)
// rgb(170.1523703626, 144.612080603, 170.1172627174)
@debug color.mix($venus, midnightblue, $method: oklch)
// rgb(95.9363315581, 74.5687109346, 133.2082569526)