symbols CSS at-rule descriptor

Syntax

symbols: A B C D E;
symbols: "\24B6" "\24B7" "\24B8" D E;
symbols: "0" "1" "2" "4" "5" "6" "7" "8" "9";
symbols: url("one.svg") url("two.svg") url("three.svg");
symbols: indic-numbers;

Values

The symbols descriptor is specified as a list of one or more space-separated <symbol> values.

<symbol>

Specifies the symbol to use within the counter system. Each symbol in the list can be either a <string>, an <image>, or a <custom-ident>. The <image> value can, in turn, be specified as a <url> or <gradient>.

Description

A symbol can be a string, image, or identifier. It is used within the @counter-style at-rule.

When the value of the system descriptor is cyclic, numeric, alphabetic, symbolic, or fixed, the symbols descriptor must be specified. For the additive system, use the additive-symbols descriptor instead to specify the symbols.

While a space between quoted symbols is not required, it makes CSS more readable. To use a quote as a symbol, either escape the quote character or enclose the character within different quotes, such as "'".

When defining symbols with identifiers instead of strings, be sure to use identifier syntax rules. For example, as noted above, ASCII non-letters such as * are not identifiers and must be either quoted or escaped. Hex escape characters are followed by a space. This space may look like the space separating two identifiers, but it enables digits to follow hex-escaped characters. This means that two spaces must be included after a hex-escaped identifier to separate it from the next identifier. For example, it is better to use the string "\2A 1" instead of \2A 1 with two spaces, as your code tools might remove double spaces. It is generally safer to quote identifiers that need to be escaped or use strings.

Formal definition

Formal syntax

symbols = 
  <symbol>+  

<symbol> = 
  <string>        |
  <image>         |
  <custom-ident>  

<image> = 
  <url>           |
  <image()>       |
  <image-set()>   |
  <cross-fade()>  |
  <element()>     |
  <gradient>      

<image()> = 
  image( <image-tags>? [ <image-src>? , <color>? ]! )  

<image-set()> = 
  image-set( <image-set-option># )  

<cross-fade()> = 
  cross-fade( <cf-image># )  

<element()> = 
  element( <id-selector> )  

<image-tags> = 
  ltr  |
  rtl  

<image-src> = 
  <url>     |
  <string>  

<image-set-option> = 
  [ <image> | <string> ] [ <resolution> || type( <string> ) ]?  

<cf-image> = 
  [ <image> | <color> ]  &&
  <percentage [0,100]>?  

<id-selector> = 
  <hash-token>  

Examples

Setting counter symbols

In this example, the list of values for the symbols descriptor include letters (A, D, E), a number within quotes ("1"), and a hex-escape identifier within quotes ("\24B7") for the character Ⓑ.

HTML

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

CSS

@counter-style symbols-example {
  system: fixed;
  symbols: A "1" "\24B7" D E;
}

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

Result

Specifications

Browser compatibility

See also

• @counter-style descriptors: system, additive-symbols, negative, prefix, suffix, range, pad, speak-as, fallback
• List style properties: list-style, list-style-image, list-style-position
• symbols() function
• <url> type
• CSS counter styles module