prefix CSS at-rule descriptor

The @counter-style rule's prefix descriptor specifies content that will be added to the beginning of the counter's marker representation.

When the counter value is negative, the prefix comes before the negative sign and any other <symbol>s added by the negative descriptor.

Syntax

css
/* <symbol> value: string, image, or identifier */
prefix: "»";
prefix: "Page ";
prefix: url("bullet.png");

Values

The prefix descriptor takes as its value a single <symbol>:

<symbol>

Specifies a <symbol> — a <string>, <image>, or <custom-ident> — that is prepended to the marker representation.

Formal definition

Related at-rule@counter-style
Initial value"" (the empty string)
Computed valueas specified

Formal syntax

prefix = 
  <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

undefined

Adding a prefix to a counter

In this example, each counter number is prefixed by "Book " (with a space) and followed by a colon (:). The colon is added with the suffix descriptor.

HTML

html
<ol class="books">
  <li>Flamer, by Mike Curato</li>
  <li>Gender Queer: A Memoir, by Maia Kobabe</li>
  <li>Tricks, by Ellen Hopkins</li>
  <li>The Handmaid's Tale: The Graphic Novel, by Margaret Atwood</li>
  <li>Crank, by Ellen Hopkins</li>
</ol>

CSS

css
@counter-style books {
  system: numeric;
  symbols: "0" "1" "2" "3" "4" "5" "6" "7" "8" "9";
  prefix: "Book ";
  suffix: ": ";
}

.books {
  list-style: books;
  padding-left: 15ch;
}

Result

Specifications

See also