Definition and Usage
The break-before CSS property describes how the page, column or region break behavior before the generated box. If there is no generated box, the property is ignored.
Each possible break point, that is each element boundary, is under the influence of three properties, the break-after value of the previous element, the break-before value of the next element and the break-inside of the containing element.
To define if a break must be done, the following rules are applied:
- If any of the three concerned values is a forced break value, that is always, left, right, page, column or region, it has precedence. If several of the concerned values is such a break, the one of the element that appears the latest in the flow is taken (that is the break-before value has precedence over the break-after value, which itself has precedence over the break-inside value).
- If any of the three concerned values is an avoid break value, that is avoid, avoid-page, avoid-region, avoid-column, no such break will be applied at that point.
Once forced breaks have been applied, soft breaks may be added if needed, but not on element boundaries that resolve in a corresponding avoid value.
- Initial auto
- Applies to block-level elements
- Inherited no
- Media paged
- Computed Value as specified
- Animatable no
- Canonical order the unique non-ambiguous order defined by the formal grammar
Syntax
Formal syntax: auto | always | avoid | left | right | page | column | avoid-page | avoid-colum
break-before: auto break-before: always break-before: left break-before: right break-before: recto break-before: verso break-before: page break-before: column break-before: region break-before: avoid break-before: avoid-page break-before: avoid-column break-before: avoid-region
Values
- auto
- Initial value. Allows, meaning neither forbid nor force, any break (either page, column or region) to be be inserted before the principle box.
- always
- Always force page breaks before the principle box. This is a synonym of page, it has been kept to facilitate transition from page-break-before which is subset of this property.
- avoid
- Prevent any break, either page, column or region, to be inserted right before the principle box.
- left
- Force one or two page breaks right before the principle box so that the next page is formatted as a left page.
- right
- Force one or two page breaks right before the principle box so that the next page is formatted as a right page.
- page
- Always force one page break right before the principle box.
- column
- Always force one column break right before the principle box.
- region
- Always force one region break right before the principle box.
- recto
- Force one or two page breaks right before the principle box so that next page is formatted as a recto page, that is a right page in a left-to-right spread or a left page in a right-to-left spread.
- verso
- Force one or two page breaks right before the principle box so that next page is formatted as a verso page, that is a left page in a left-to-right spread or a left right in a right-to-left spread.
- avoid-page
- Avoid any page break right before the principle box.
- avoid-column
- Avoid any column break right before the principle box.
- avoid-region
- Avoid any region break right before the principle box.
Examples
No examplesCompatibility
Desktop browsers
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | Not supported | Not supported | 10 | 11.10 | Not supported |
column , avoid-column | Not supported | Not supported | 10 | 11.10 | Not supported |
recto , verso | Not supported | Not supported | Not supported | Not supported | Not supported |
region , avoid-region | Not supported | Not supported | Not supported | Not supported | Not supported |
Mobile browsers
Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | Not supported | Not supported | NA | NA | Not supported |
column , avoid-column | Not supported | Not supported | NA | NA | Not supported |
recto , verso | Not supported | Not supported | Not supported | Not supported | Not supported |
region , avoid-region | Not supported | Not supported | Not supported | Not supported | Not supported |