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Summary
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 | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | (Yes) | 49.0 (49.0) | (Yes) | (Yes) | (Yes) |
| Two-value syntax (support for offsets from any edge) | No support | 49.0 (49.0) | (Yes) | No support | ? |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | (Yes) | 49.0 (49.0) | ? | ? | (Yes) |
| Two-value syntax (support for offsets from any edge) | ? | 49.0 (49.0) | ? | ? | ? |