CSS fallback Descriptor

The CSS fallback descriptor is used with the @counter-style at-rule to provide a fallback counter system when the current counter style can't be used.

The @counter-style rule accepts a name, followed by a number of descriptors, which define the counter style. The fallback descriptor allows you to specify a fallback counter system when the current counter style can’t create a representation for a given counter value.

Here's an example of using the fallback descriptor.

If your browser supports the @counter-style at-rule, the above code could result in a list that looks something like this:

Possible Values

The fallback descriptor accepts the following values.

The counter-style-name is the name of a counter style (i.e. the counter style you want to use as the fallback style).

The initial value of the fallback descriptor is decimal. Therefore, if there's no counter style with the given name, the counter will use decimal instead.

Official Specifications

The fallback descriptor is defined in CSS Counter Styles Level 3 (W3C Candidate Recommendation, 11 June 2015).