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CSS mask Property

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Definition and Usage

mask The property is used to hide elements by masking or clipping images (partially or entirely).

mask The property is a shorthand for the following properties:

Instance

Example 1

Create a mask layer for images:

.mask1 {
  mask: url(w3logo.png) no-repeat 50% 50%;
}

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Example 2

Create different mask layers for images using linear gradients and radial gradients:

.mask1 {
  mask: linear-gradient(black, transparent);
}
.mask2 {
  mask: radial-gradient(circle, black 50%, rgba(0, 0, 0, 0.5) 50%);
}
.mask3 {
  mask: radial-gradient(ellipse, black 50%, rgba(0, 0, 0, 0.5) 50%);
}

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Example 3

Use the SVG <mask> element to create a mask layer for images:

<svg width="600" height="400">
  <mask id="svgmask1">
    <polygon fill="#ffffff" points="100,10 40,198 190,78 10,78 160,198"></polygon>
  </mask>
  <image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="img_5terre.jpg" mask="url(#svgmask1)"></image>
</svg>

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Example 4

Use the SVG <mask> element to create a mask layer for images:

<svg width="600" height="400">
  <mask id="svgmask1">
    <circle fill="#ffffff" cx="75" cy="75" r="75"></circle>
    <circle fill="#ffffff" cx="80" cy="260" r="75"></circle>
    <circle fill="#ffffff" cx="270" cy="160" r="75"></circle>
  </mask>
  <image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="img_5terre.jpg" mask="url(#svgmask1)"></image>
</svg>

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CSS Syntax

mask-image: mask-image mask-mode mask-repeat mask-position mask-clip mask-origin mask-size mask-composite|initial|inherit;

Property Value

Value	Description
mask-image	Specifies the image used as the element mask layer. The default value is none.
mask-mode	Specifies whether the mask layer image should be considered as a luminance mask or an alpha mask. The default value is match-source.
mask-repeat	Sets whether and how the mask image is repeated. The default value is repeat.
mask-position	Sets the starting position of the mask image (relative to the mask position area). The default value is 0% 0%.
mask-clip	Specifies the area affected by the mask image. The default value is border-box.
mask-origin	Specifies the starting position of the mask layer image (the mask position area). The default value is border-box.
mask-size	Specifies the size of the mask layer image. The default value is auto.
mask-composite	Specifies the composite operation used between the current mask layer and the layer below it. The default value is add.
initial	Sets this property to its default value. See: initial.
inherit	Inherits this property from its parent element. See: inherit.

Technical Details

Default Value:	none match-source repeat 0% 0% border-box border-box auto add
Inheritance:	No
Animation creation:	Not supported. See:Animation-related properties.
Version:	CSS Masking Module Level 1
JavaScript Syntax:	object.style.mask="url(star.svg)"