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background-position-x

The background-position-x CSS property sets the initial horizontal 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.

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	`left`
Applies to	all elements
Inherited	no
Percentages	refer to width 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-x: left;
background-position-x: center;
background-position-x: right;

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

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

/* side-relative values */
background-position-x: right 3px;
background-position-x: left 25%;

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

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

Values

left: Aligns the left edge of the background image with the left edge of the background position layer.
center: Aligns the center of the background image with the center of the background position layer.
right: Aligns the right edge of the background image with the right edge of the background position layer.
<length>: A <length> value defines the offset of the given background image's horizontal edge from the corresponding background position layer's horitzontal edge. If no edge is mentioned, it refers to the left edge.
<percentage>: A <percentage> value defining the offset of the given background image's horitzontal edge from the corresponding background position layer's horitzontal edge relative to its width. If no edge is given, it refers to the left edge by default.

Formal syntax

[ center | [ left | right | x-start | x-end ]? <length-percentage>? ]#where 
<length-percentage> = <length> | <percentage>

Specifications

Specification	Status	Comment
CSS Backgrounds and Borders Module Level 4 The definition of 'background-position-x' in that specification.	Editor's Draft	Initial specification of longhand sub properties 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	?