Property Reference - CSS Reference - page 277

Name
break-before
Values:
auto | always | avoid | left | right | page | column | avoid-page | avoid-column
Initial value:
auto
Applies to:
Block-level elements
Inherited:
No
Computed value:
Same as declared value
Description:
Defines whether a column or page break should or should not be placed before the element.
Although it is theoretically possible to force breaks with always , it is not possible to guarantee
prevention; the best an author can do is ask the user agent to avoid inserting a column or page
break before the element. The keywords avoid-column and avoid-page attempt to prevent
insertion before the element of column or page breaks, respectively. The keyword left is used
to insert enough breaks before the element to make the page be a left-hand page; similarly,
right is used for a right-hand page. page and always insert a page break before the element;
column and always , a column break.
Examples:
h2 {break-before: always;}
h3 {break-before: avoid;}