mask-image

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

Initial value	none
Applies to	all elements; In SVG, it applies to container elements excluding the <defs> element and all graphics elements
Inherited	no
Media	visual
Computed value	as specified, but with URIs made absolute
Animation type	discrete
Canonical order	the unique non-ambiguous order defined by the formal grammar

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}
<position> = [[ left | center | right | top | bottom | <length-percentage> ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ] | [ center | [ left | right ] <length-percentage>? ] && [ center | [ top | bottom ] <length-percentage>? ]]
where 
<rgb-component> = <integer> | <percentage>
<alpha-value> = <number>
<hue> = <number>
<color-stop> = <color> <length-percentage>?
<length-percentage> = <length> | <percentage>

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>

Specifications

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

Browser compatibility

[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. It is only available in Nightly and Dev Edition. 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.