fallback - CSS: Cascading Style Sheets 编辑

The fallback descriptor can be used to specify a counter style to fall back to if the current counter style cannot create a marker representation for a particular counter value.

Syntax

/* Keyword values */
fallback: lower-alpha;
fallback: custom-gangnam-style;

Description

If the specified fallback style is also unable to construct a representation, then its fallback style will be used. If a valid fallback style is not specified, it defaults to decimal.

A couple of scenarios where a fallback style will be used are:

• When the range descriptor is specified for a counter style, the fallback style will be used to represent values that fall outside the range.
• When the fixed system is used and there are not enough symbols to cover all the list items, the fallback style will be used for the rest of the list items.

Formal definition

Formal syntax

<counter-style-name>
where 
<counter-style-name> = <custom-ident>

Examples

Specifying a fallback counter style

HTML

<ul class="list">
  <li>One</li>
  <li>Two</li>
  <li>Three</li>
  <li>Four</li>
  <li>Five</li>
</ul>

CSS

@counter-style fallback-example {
  system: fixed; symbols: "\24B6" "\24B7" "\24B8";
  fallback: upper-alpha;
}

.list {
  list-style: fallback-example;
}

Result

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• list-style, list-style-image, list-style-position
• symbols(): the functional notation creating anonymous counter styles