-webkit-mask-position-y - CSS: Cascading Style Sheets

Non-standard
This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.

The -webkit-mask-position-y CSS property sets the initial vertical position of a mask image.

/* Keyword values */
-webkit-mask-position-y: top;
-webkit-mask-position-y: center;
-webkit-mask-position-y: bottom;

/* <percentage> values */
-webkit-mask-position-y: 100%;
-webkit-mask-position-y: -50%;

/* <length> values */
-webkit-mask-position-y: 50px;
-webkit-mask-position-y: -1cm;

/* Multiple values values */
-webkit-mask-position-y: 50px, 25%, -3em;

/* Global values */
-webkit-mask-position-y: inherit;
-webkit-mask-position-y: initial;
-webkit-mask-position-y: unset;

Initial value	`0%`
Applies to	all elements
Inherited	no
Percentages	refer to the size of the box itself
Computed value	for `<length>` the absolute value, otherwise a percentage
Animation type	discrete

Syntax

Values

<length-percentage>: A length indicating the position of the top side of the image relative to the box's top padding edge. Percentages are calculated against the vertical dimension of the box padding area. A value of 0% means the top edge of the image is aligned with the box's top padding edge and a value of 100% means the bottom edge of the image is aligned with the box's bottom padding edge.
top: Equivalent to 0%.
bottom: Equivalent to 100%.
center: Equivalent to 50%.

Formal definition

Initial value	`0%`
Applies to	all elements
Inherited	no
Percentages	refer to the size of the box itself
Computed value	for `<length>` the absolute value, otherwise a percentage
Animation type	discrete

Formal syntax

[ <length-percentage> | top | center | bottom ]#where 
<length-percentage> = <length> | <percentage>

Examples

Vertically positioning a mask image

.exampleOne {
  -webkit-mask-image: url(mask.png);
  -webkit-mask-position-y: bottom;
}

.exampleTwo {
  -webkit-mask-image: url(mask.png);
  -webkit-mask-position-y: 25%;
}

Specifications

Not part of any standard.

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`-webkit-mask-position-y` Non-standard	Chrome Full support 1	Edge Full support 18	Firefox Full support 49	IE No support No	Opera Full support 15	Safari Full support 3.2	WebView Android Full support 2	Chrome Android Full support 18	Firefox Android Full support 49	Opera Android Full support 14	Safari iOS Full support 3.2	Samsung Internet Android Full support 1.0

Legend

Full support: Full support
No support: No support
Non-standard. Expect poor cross-browser support.: Non-standard. Expect poor cross-browser support.