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Summary
The break-before
CSS property describes 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
orregion
, 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 thebreak-before
value has precedence over thebreak-after
value, which itself has precedence over thebreak-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 value | auto |
---|---|
Applies to | block-level elements |
Inherited | no |
Media | paged |
Computed value | as specified |
Animation type | discrete |
Canonical order | the unique non-ambiguous order defined by the formal grammar |
Syntax
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 frompage-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 right page 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.
Formal syntax
auto | avoid | avoid-page | page | left | right | recto | verso | avoid-column | column | avoid-region | region
Specifications
Specification | Status | Comment |
---|---|---|
CSS Fragmentation Module Level 3 The definition of 'break-before' in that specification. |
Candidate Recommendation | Adds the recto and verso keywords. Changes the media type of this property from paged to visual . Precises the breaking algorithm with different kinds of breaks. |
CSS Regions Module Level 1 The definition of 'break-before' in that specification. |
Working Draft | Extends the property to handle region breaks. Adds the avoid-region and region keywords. |
CSS Multi-column Layout Module The definition of 'break-before' in that specification. |
Candidate Recommendation | Initial definition. Extends the CSS 2.1 page-break-before property to handle both page and column breaks. |
Browser compatibility
Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|
Basic support | No support [*] | No support | 10 | 11.10 | No support [*] |
column , avoid-column |
No support [*] | No support | 10 | 11.10 | No support [*] |
recto , verso |
No support | No support | No support | No support | No support |
region , avoid-region |
No support [*] | No support | No support | No support | No support [*] |
Feature | Android | Firefox Mobile (Gecko) | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|
Basic support | No support [*] | No support | ? | ? | No support [*] |
column , avoid-column |
No support [*] | No support | ? | ? | No support [*] |
recto , verso |
No support | No support | No support | No support | No support |
region , avoid-region |
No support [*] | No support | No support | No support | No support[*] |
[*] WebKit and Blink browsers don't support this property, but some have the non-standard -webkit-column-break-before
and -webkit-region-break-before
with similar parameters as page-break-before
.