Wide Gamut Color in CSS with Display-P3

Display-P3 color space includes vivid colors that aren’t available in sRGB.

CSS Color Module Level 4 introduced syntax to use Display-P3 color space on the web:

color: color(display-p3 1 0.5 0)

The previously available syntax defined colors in sRGB color space. hsl(42, 70%, 50%), rgb(3, 5, 11), #abc — all of these colors are in the sRGB color space.

Display-P3 is a superset of sRGB. It’s around 35% larger:

The white line shows the edge of sRGB. Everything on its top right is Display-P3 colors not available in sRGB. Note how greens is greatly expanded while blues aren’t nearly as much.

Browser support

WebKit has had support for Display-P3 color since 2016 (r207442). The following browsers support Display-P3 color:

• Safari on macOS Mojave and newer

• Safari on iOS 11 and newer

WebKit is the only browser engine that supports Display-P3 color as of January 2020.

Graceful degradation

One way to provide a fallback is to include the same property with the sRGB color before:

header {
    color: rgb(0, 255, 0);
    color: color(display-p3 0 1 0);
}

Browsers other than WebKit currently parse color(...) as invalid value. CSS properties with invalid values are ignored by the browsers.

Alternatively, you can use @supports feature query. This is particularly useful when defining variables with colors:

/* sRGB color. */
:root {
    --bright-green: rgb(0, 255, 0);
}

/* Display-P3 color, when supported. */
@supports (color: color(display-p3 1 1 1)) {
    :root {
        --bright-green: color(display-p3 0 1 0);
    }
}

header {
    color: var(--bright-green);
}

Hardware support

• iPhone 7 and newer

• MacBook Pro (since 2016)

• iMac (since 2015)

• iPad Pro (since 2016)

• LG UltraFine 5K Display

There are also numerous devices that support Display-P3 color space but currently have no browsers that support Display-P3 in CSS:

• Google Pixel 2 XL

• Google Pixel 3

• HTC U11+

• OnePlus 6

Hardware support can be detected with a media query in CSS:

@media (color-gamut: p3) {
    /* Do colorful stuff. */
}

And JavaScript:

if (window.matchMedia("(color-gamut: p3)").matches) {
    // Do colorful stuff.
}

Web Inspector

Starting Safari Technology Preview 97, Web Inspector includes P3-capable color picker:

The white line draws the edge sRGB color space. All colors on the top right of it are only available in Display-P3 color space.

Right-clicking the color square shows an option to convert to sRGB color space:

When the color is within sRGB color space, “Convert to sRGB” menu item is displayed. When it outside — “Clamp to sRGB”.

Web Inspector also includes context menus to convert sRGB colors to Display-P3:

Closing thoughts

CSS has syntax to define colors in Display-P3 color space, which includes vivid colors previously not available in sRGB. Many modern displays cover 100% of the P3 color standard. Web Inspector now includes P3-capable color picker.

Source: Webkit

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