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The revert
CSS keyword rolls back the cascade so that the property takes on the value it would have had if there were no styles in the current style origin (author, user, or user-agent). In author stylesheets (the normal case), for the purposes of the given declaration, it's as if there were no author-level styles, thus resetting the property to the default value established by the user-agent stylesheet (or by user styles, if any exist).
The revert
keyword is different from and should not be confused with initial
, which uses the initial value defined on a per-property basis by the CSS specifications. By contrast, user-agent stylesheets set default values on the basis of CSS selectors. For example, the initial value for the display
property is inline
, whereas a normal user-agent stylesheet sets the default display
value of <div>
s to block
, of <table>
s to table
, etc.
The revert
keyword is useful for isolating embedded widgets/components from the styles of the page that contains them, particularly when used with the all
property.
In user stylesheets, revert
rolls back the cascade and resets the property to the default value established by the user-agent stylesheet.
Example
This article is currently a stub and is missing an example.
Specifications
Specification | Status | Comment |
---|---|---|
CSS Cascading and Inheritance Level 4 The definition of 'revert' in that specification. |
Working Draft | Initial definition |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | No support[3] | No support[2] | ? | ? | 9.1[1] |
Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | No support[3] | No support[2] | ? | ? | 9.3[1] |
[1] See WebKit bug 149702.
[2] See bug 1215878.
[3] See Chromium bug 579788