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content

The content CSS property is used with the ::before and ::after pseudo-elements to generate content in an element. Objects inserted using the content property are anonymous replaced elements.

/* Keywords that cannot be combined with other values */
content: normal;
content: none;

/* <string> value, non-latin characters must be encoded */
/* e.g. \00A0 for &nbsp; */
content: "prefix";

/* <url> value */
content: url("http://www.example.com/test.png");

/* <counter> values */
content: counter(chapter_counter);
content: counters(section_counter, ".");

/* attr() value linked to the HTML attribute value */
content: attr(value string);

/* Language- and position-dependent keywords */
content: open-quote;
content: close-quote;
content: no-open-quote;
content: no-close-quote;

/* Except for normal and none, several values */
/* can be used simultaneously */
content: open-quote chapter_counter;

/* Global values */
content: inherit;
content: initial;
content: unset;
Initial value normal
Applies to ::before and ::after pseudo-elements
Inherited no
Media all
Computed value On elements, always computes to normal. On ::before and ::after, if normal is specified, computes to none. Otherwise, for URI values, the absolute URI; for attr() values, the resulting string; for other keywords, as specified.
Animation type discrete
Canonical order the unique non-ambiguous order defined by the formal grammar

Syntax

Values

none
The pseudo-element is not generated.
normal
Computes to none for the ::before and ::after pseudo-elements.
<string>
One or more text characters.
<url>
A URL that designates an external resource (such as an image). If the resource can't be displayed, it is either ignored or a placeholder is shown.
<counter>
The value of a CSS counter, generally a number. It can be displayed using either the counter() or counters() function.

The counter() function has two forms: 'counter(name)' or 'counter(name, style)'. The generated text is the value of the innermost counter of the given name in scope at the given pseudo-element. It is formatted in the specified style (decimal by default).

The counters() function also has two forms: 'counters(name, string)' or 'counters(name, string, style)'. The generated text is the value of all counters with the given name in scope at the given pseudo-element, from outermost to innermost, separated by the specified string. The counters are rendered in the indicated style (decimal by default).

attr(x)
The value of the element's attribute x as a string. If there is no attribute x, an empty string is returned. The case-sensitivity of attribute names depends on the document language.
open-quote | close-quote
These values are replaced by the appropriate string from the quotes property.
no-open-quote | no-close-quote
Introduces no content, but increments (decrements) the level of nesting for quotes.

Formal syntax

normal | none | [ <content-replacement> | <content-list> ] [/ <string> ]?

where
<content-replacement> = <image>
<content-list> = [ <string> | contents | <image> | <quote> | <target> | <leader()> ]+

where
<image> = <url> | <image()> | <image-set()> | <element()> | <cross-fade()> | <gradient>
<quote> = open-quote | close-quote | no-open-quote | no-close-quote
<target> = <target-counter()> | <target-counters()> | <target-text()>
<leader()> = leader( <leader-type> )

where
<image()> = image( [ [ <image> | <string> ]? , <color>? ]! )
<image-set()> = image-set( <image-set-option># )
<element()> = element( <id-selector> )
<cross-fade()> = cross-fade( <cf-mixing-image> , <cf-final-image>? )
<gradient> = <linear-gradient()> | <repeating-linear-gradient()> | <radial-gradient()> | <repeating-radial-gradient()>
<target-counter()> = target-counter( [ <string> | <url> ] , <custom-ident> , <counter-style>? )
<target-counters()> = target-counters( [ <string> | <url> ] , <custom-ident> , <string> , <counter-style>? )
<target-text()> = target-text( [ <string> | <url> ] , [ content | before | after | first-letter ]? )
<leader-type> = dotted | solid | space | <string>

where
<color> = <rgb()> | <rgba()> | <hsl()> | <hsla()> | <hex-color> | <named-color> | currentcolor | <deprecated-system-color>
<image-set-option> = [ <image> | <string> ] <resolution>
<cf-mixing-image> = <percentage>? && <image>
<cf-final-image> = <image> | <color>
<linear-gradient()> = linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
<repeating-linear-gradient()> = repeating-linear-gradient( [ <angle> | to <side-or-corner> ]? , <color-stop-list> )
<radial-gradient()> = radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )
<repeating-radial-gradient()> = repeating-radial-gradient( [ <ending-shape> || <size> ]? [ at <position> ]? , <color-stop-list> )
<counter-style> = <counter-style-name> | symbols()

where
<rgb()> = rgb( [ [ <percentage>{3} | <number>{3} ] [ / <alpha-value> ]? ] | [ [ <percentage>#{3} | <number>#{3} ] , <alpha-value>? ] )
<rgba()> = rgba( [ [ <percentage>{3} | <number>{3} ] [ / <alpha-value> ]? ] | [ [ <percentage>#{3} | <number>#{3} ] , <alpha-value>? ] )
<hsl()> = hsl( [ <hue> <percentage> <percentage> [ / <alpha-value> ]? ] | [ <hue>, <percentage>, <percentage>, <alpha-value>? ] )
<hsla()> = hsla( [ <hue> <percentage> <percentage> [ / <alpha-value> ]? ] | [ <hue>, <percentage>, <percentage>, <alpha-value>? ] )
<side-or-corner> = [ left | right ] || [ top | bottom ]
<color-stop-list> = <color-stop>#{2,}
<ending-shape> = circle | ellipse
<size> = closest-side | farthest-side | closest-corner | farthest-corner | <length> | <length-percentage>{2}
<position> = [[ left | center | right | top | bottom | <length-percentage> ] | [ left | center | right | <length-percentage> ] [ top | center | bottom | <length-percentage> ] | [ center | [ left | right ] <length-percentage>? ] && [ center | [ top | bottom ] <length-percentage>? ]]
<counter-style-name> = <custom-ident>

where
<alpha-value> = <number> | <percentage>
<hue> = <number> | <angle>
<color-stop> = <color> <length-percentage>?
<length-percentage> = <length> | <percentage>

Examples

Headings and quotes

This example inserts quotation marks around quotes, and adds the word "Chapter" before headings.

HTML

<h1>5</h1>
<p>According to Sir Tim Berners-Lee,
  <q cite="http://www.w3.org/People/Berners-Lee/FAQ.html#Internet">I was
    lucky enough to invent the Web at the time when the Internet
    already existed - and had for a decade and a half.</q>
  We must understand that there is nothing fundamentally wrong
  with building on the contributions of others.
</p>

<h1>6</h1>
<p>According to the Mozilla Manifesto,
  <q cite="http://www.mozilla.org/en-US/about/manifesto/">Individuals
    must have the ability to shape the Internet and
    their own experiences on the Internet.</q>
  Therefore, we can infer that contributing to the open web
  can protect our own individual experiences on it.
</p>

CSS

q {
  color: blue;
}

q::before {
  content: open-quote;
}

q::after {
  content: close-quote;
}

h1::before  {
  content: "Chapter ";  /* The trailing space creates separation
                           between the added content and the
                           rest of the content */
}

Result

Image combined with text

This example inserts an image before the link. If the image is not found, it inserts text instead.

HTML

<a href="http://www.mozilla.org/en-US/">Mozilla Home Page</a>

CSS

a::before {
  content: url("https://mozorg.cdn.mozilla.net/media/img/favicon.ico") " MOZILLA: ";
  font: x-small Arial, sans-serif;
  color: gray;
}

Result

Targeting classes

This example inserts additional text after special items in a list.

HTML

<h2>Paperback Best Sellers</h2>
<ol>
  <li>Political Thriller</li>
  <li class="new-entry">Halloween Stories</li>
  <li>My Biography</li>    
  <li class="new-entry">Vampire Romance</li>
</ol>

CSS

.new-entry::after {
  content: " New!";  /* The leading space creates separation
                        between the added content and the
                        rest of the content */
  color: red;
}

Result

Images and element attributes

This example inserts an image before each link, and adds its id attribute after.

HTML

<ul>
  <li><a id="moz" href="http://www.mozilla.org/">
    Mozilla Home Page</a></li>
  <li><a id="mdn" href="https://developer.mozilla.org/">
    Mozilla Developer Network</a></li>
</ul>

CSS

a {
  text-decoration: none;
  border-bottom: 3px dotted navy;
}

a::after {
  content: " (" attr(id) ")";
}

#moz::before {
  content: url("https://mozorg.cdn.mozilla.net/media/img/favicon.ico") ;
}

#mdn::before {
  content: url("https://mdn.mozillademos.org/files/7691/mdn-favicon16.png") ;
}

li {
  margin: 1em;
}

Result

Specifications

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 1 Yes 1 8 4 1
url() 1 ? 1 8 7 1
Feature Android webview Chrome for Android Edge mobile Firefox for Android Opera Android iOS Safari Samsung Internet
Basic support 1 Yes Yes 4 9.5 1 ?
url() ? ? ? ? ? ? ?

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/CSS/content