CSS background-origin
The CSS background-origin
property was introduced in CSS3 for the purposes of setting the background positioning area of an element.
The background-origin
property allows you to specify whether the background will be positioned relative to the "content box", "border box", or the "padding box".
The background-origin
property can be used in conjunction with the background-clip
and background-image
properties to modify the position of a background image to match the clipping effect (supplied by the background-clip
property).
In CSS3, the background-origin
property has been added to the background
shorthand property. This means that you can set the background-origin
from within the background
property (for example, background: url("background.png") 40% / 10em lightblue round fixed border-box;
).
Syntax
The formal syntax for this property is:
Where
Below is an explanation of these values.
Possible Values
border-box
- Specifies that the background position is relative to the border box.
padding-box
- Specifies that the background position is relative to the padding box.
content-box
- Specifies that the background position is relative to the content box.
In addition, all CSS properties also accept the following CSS-wide keyword values as the sole component of their property value:
initial
- Represents the value specified as the property's initial value.
inherit
- Represents the computed value of the property on the element's parent.
unset
- This value acts as either
inherit
orinitial
, depending on whether the property is inherited or not. In other words, it sets all properties to their parent value if they are inheritable or to their initial value if not inheritable.
Basic Property Information
- Initial Value
padding-box
- Applies To
- All elements
- Inherited?
- No
- Media
- Visual
- Animatable
- No
Example Code
Basic CSS
Working Example within an HTML Document
CSS Specifications
- The
background-origin
property is defined in CSS Backgrounds and Borders Module Level 3 (W3C Candidate Recommendation 9 September 2014)
Browser Support
The following table provided by Caniuse.com shows the level of browser support for this feature.
Vendor Prefixes
For maximum browser compatibility many web developers add browser-specific properties by using extensions such as -webkit-
for Safari, Google Chrome, and Opera (newer versions), -ms-
for Internet Explorer, -moz-
for Firefox, -o-
for older versions of Opera etc. As with any CSS property, if a browser doesn't support a proprietary extension, it will simply ignore it.
This practice is not recommended by the W3C, however in many cases, the only way you can test a property is to include the CSS extension that is compatible with your browser.
The major browser manufacturers generally strive to adhere to the W3C specifications, and when they support a non-prefixed property, they typically remove the prefixed version. Also, W3C advises vendors to remove their prefixes for properties that reach Candidate Recommendation status.
Many developers use Autoprefixer, which is a postprocessor for CSS. Autoprefixer automatically adds vendor prefixes to your CSS so that you don't need to. It also removes old, unnecessary prefixes from your CSS.
You can also use Autoprefixer with preprocessors such as Less and Sass.