CSS - mask-image

The mask-image CSS property sets the image that is used as mask layer for an element.

Example

CSS Content

#masked {
  width: 100px;
  height: 100px;
  background-color: #8cffa0;
  mask-image: url(https://mdn.mozillademos.org/files/12676/star.svg);
}

HTML Content

<div id="masked"></div>

Syntax  

/* Keyword value */
mask-image: none;

/* <mask-source> value */
mask-image: url(masks.svg#mask1);

/* <image< values */
mask-image: linear-gradient(rgba(0, 0, 0, 1.0), transparent);
mask-image: image(url(mask.png), skyblue);

/* Multiple values */
mask-image: image(url(mask.png), skyblue), linear-gradient(rgba(0, 0, 0, 1.0), transparent);

/* Global values */
mask-image: inherit;
mask-image: initial;
mask-image: unset;

Values

none
This keyword is interpreted as a transparent black image layer.
<mask-source>
A <url> reference to a <mask> or to a CSS image.
<image>
An image value used as mask image layer.

Formal syntax

<mask-reference>#

where
<mask-reference> = none | <image> | <mask-source>

where
<image> = <url> | <image()> | <image-set()> | <element()> | <cross-fade()> | <gradient>
<mask-source> = <url>

where
<image()> = image( [ [ <image> | <string> ]? , <color>? ]! )
<image-set()> = image-set( <image-set-option># )
<element()> = element( <id-selector> )
<cross-fade()> = cross-fade( <cf-mixing-image> , <cf-final-image>? )
<gradient> = <linear-gradient()> | <repeating-linear-gradient()> | <radial-gradient()> | <repeating-radial-gradient()>

where
<color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>
<image-set-option> = [ <image> | <string> ] <resolution>
<cf-mixing-image> = <percentage>? && <image>
<cf-final-image> = <image> | <color>
<linear-gradient()> = linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
<repeating-linear-gradient()> = repeating-linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
<radial-gradient()> = radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )
<repeating-radial-gradient()> = repeating-radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )

where
<rgb()> = rgb( <rgb-component>#{3} )
<rgba()> = rgba( <rgb-component>#{3} , <alpha-value> )
<hsl()> = hsl( <hue>, <percentage>, <percentage> )
<hsla()> = hsla( <hue>, <percentage>, <percentage>, <alpha-value> )
<named-color> = <ident>
<deprecated-system-color> = ActiveBorder | ActiveCaption | AppWorkspace | Background | ButtonFace | ButtonHighlight | ButtonShadow | ButtonText | CaptionText | GrayText | Highlight | HighlightText | InactiveBorder | InactiveCaption | InactiveCaptionText | InfoBackground | InfoText | Menu | MenuText | Scrollbar | ThreeDDarkShadow | ThreeDFace | ThreeDHighlight | ThreeDLightShadow | ThreeDShadow | Window | WindowFrame | WindowText
<side-or-corner> = [ left | right ] || [ top | bottom ]
<color-stop-list> = <color-stop>{2,}
<ending-shape> = circle | ellipse
<size> = closest-side | farthest-side | closest-corner | farthest-corner | <length> | [ <length> | <percentage> ]{2}

where
<rgb-component> = <integer> | <percentage>
<alpha-value> = <number>
<hue> = <number>
<color-stop> = <color> [ <percentage> | <length> ]?

Description  

The mask-image CSS property sets the image that is used as mask layer for an element.

Initial valuenone
Applies toall elements; In SVG, it applies to container elements excluding the <defs> element and all graphics elements
Inheritedno
Mediavisual
Computed valueas specified, but with URIs made absolute
Animatableno
Canonical orderthe unique non-ambiguous order defined by the formal grammar

Browser Compatibility  

Feature Chrome Firefox (Gecko) Internet Explorer Edge Opera Safari (WebKit)
Basic support 1.0-webkit[1] No support[2] No support ? (Yes)-webkit 4.0-webkit[3]
Multiple mask images 1.0-webkit No support[2] No support ? (Yes)-webkit 4.0-webkit
SVG masks 8.0 No support[2] No support ? (Yes)-webkit 4.0-webkit
Feature Android Firefox Mobile (Gecko) IE Phone Opera Mobile Safari Mobile
Basic support 2.1-webkit[4] No support[2] ? No support 3.2-webkit[5]
Multiple mask images (Yes)-webkit No support[2] ? No support (Yes)-webkit
SVG masks (Yes)-webkit No support[2] ? No support (Yes)-webkit

[1] Implemented in version 8.0, Chrome initially only supported the -webkit prefixed versions of gradients as values. Later, support for the unprefixed versions was added.

[2] This feature is not implemented yet. See bug 1251161.

[3] Implemented in version 4.0, Safari initially only supported the -webkit prefixed versions of gradients as values.

[4] Android initially only supported the -webkit prefixed versions of gradients as values.

[5] iOS Safari initially only supported the -webkit prefixed versions of gradients as values.

Specifications  

Specification Status Comment
CSS Masking Level 1
The definition of 'mask-image' in that specification.
Candidate Recommendation Initial definition

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/css/mask-image