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background-position-y

The background-position-y CSS property sets the initial vertical position, relative to the background position layer defined by background-origin for each defined background image- For more information, see the background-position property, which has been widely supported for much longer.

Note: The value of this property is overridden by any declaration of the background or background-position shorthand properties applied to the element after the background-position-x CSS property.

Initial value	`top`
Applies to	all elements
Inherited	no
Percentages	refer to height of background positioning area minus height of background image
Media	visual
Computed value	A list, each item consisting of: an offset given as a combination of an absolute length and a percentage, plus an origin keyword
Animation type	discrete
Canonical order	the unique non-ambiguous order defined by the formal grammar

Syntax

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

/* <percentage> values */
background-position-y: 25%;

/* <length> values */
background-position-y: 0px;
background-position-y: 1cm;
background-position-y: 8em;

/* side-relative values */
background-position-y: bottom 3px;
background-position-y: bottom 10%;

/* Multiple values */
background-position-y: 0px, center;

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

Values

top: Aligns the top edge of the background image with the top edge of the background position layer.
center: Aligns the vertical center of the background image with the vertical center of the background position layer.
bottom: Aligns the bottom edge of the background image with the bottom edge of the background position layer.
<length>: A <length> value defining the offset of the given background image's vertical edge from the corresponding background position layer's vertical edge. If no edge is given, it refers to the top edge.
<percentage>: A <percentage> value defining the offset of the given background image's vertical edge from the corresponding background position layer's vertical edge relative to its height. If no edge is given, it refers to the top edge.

Formal syntax

[ center | [ top | bottom | y-start | y-end ]? <length-percentage>? ]#where 
<length-percentage> = <length> | <percentage>

Specifications

Specification	Status	Comment
CSS Backgrounds and Borders Module Level 4 The definition of 'background-position-y' in that specification.	Editor's Draft	Initial specification of longhand subproperties of `background-position`, to match longstanding implementations.

Browser compatibility

Feature	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Servo
Basic Support	(Yes)	12	49.0	6	(Yes)	(Yes)	?
Two-value syntax (support for offsets from any edge)	No support	12	49.0	9.0	No support	No support	?

Feature	Android	Chrome for Android	Edge Mobile	Firefox for Android	IE Mobile	Opera Mobile	Safari Mobile
Basic Support	(Yes)	(Yes)	(Yes)	49.0	?	?	?
Two-value syntax (support for offsets from any edge)	No support	No support	(Yes)	49.0	?	No support	No support

background-position-y