CSS generated content

{{CSSRef}} 

The CSS generated content module defines how an element’s content can be replaced and content can be added to a document with CSS.

Generated content can be used for content replacement, in which case the content of a DOM node is replaced with a CSS <image>. The CSS generated content also enables generating language-specific quotes, creating custom list item numbers and bullets, and visually adding content by generating content on select pseudo-elements as anonymous replaced elements.

Generated content in action

<div></div>

body,
div {
  background-repeat: no-repeat;
}
body {
  background-image: linear-gradient(#3a67ab, #e8f6ff 100%);
}
div {
  position: relative;
  width: 400px;
  height: 400px;
  background-image:
    linear-gradient(
      115deg,
      transparent 48%,
      brown,
      #996600,
      brown,
      transparent 52%
    ),
    linear-gradient(
      60deg,
      transparent 48%,
      brown,
      #996600,
      brown,
      transparent 52%
    ),
    radial-gradient(
      circle 10px at 50% 50%,
      #333333 30%,
      #999999 50%,
      transparent 50%
    ),
    radial-gradient(
      circle 10px at 50% 50%,
      #333333 30%,
      #999999 50%,
      transparent 50%
    ),
    radial-gradient(circle at 50% 50%, white 30%, #eeeeee 50%, transparent 50%),
    radial-gradient(circle at 50% 50%, white 30%, #eeeeee 50%, transparent 50%),
    radial-gradient(circle at 50% 50%, white 30%, #eeeeee 50%, transparent 50%);
  background-size:
    100px 100px,
    100px 100px,
    15px 15px,
    15px 15px,
    200px 200px,
    300px 300px,
    400px 400px;
  background-position:
    95% 120px,
    5% 120px,
    46% 80px,
    54% 80px,
    50% 0,
    50% 90px,
    50% 220px;
}
div::after {
  content: "";
  border: transparent solid 4px;
  border-left: orange 30px solid;
  height: 1px;
  width: 1px;
  position: absolute;
  left: 50%;
  top: 100px;
}

div::before {
  content: "Only one <div>";
  font-size: min(6vh, 2rem);
  justify-content: center;
  display: flex;
  font-family: comic-sans, papyrus, sans-serif;
}

{{EmbedLiveSample("generated_content", "", "400px")}} 

The HTML for this sample is a single, empty {{HTMLElement("div")}}  inside an otherwise empty {{HTMLElement("body")}} . The snowman was created with CSS images and CSS backgrounds and borders. The carrot nose was added using generated content: an empty box with a wide orange left border added to the {{cssxref("::before")}}  pseudo-element. The text is also generated content: “only one <div>” was generated with the {{cssxref("content")}}  property applied to the {{cssxref("::after")}}  pseudo-element.

Click “Play” in the example above to see or edit the code in the MDN Playground.

Reference

Properties

• {{cssxref("content")}} 
• {{cssxref("quotes")}} 

[!NOTE] The CSS generated content module introduces four at-risk properties that have not been implemented: string-set, bookmark-label, bookmark-level, and bookmark-state.

Functions

The CSS generated content module introduces six yet-to-be implemented CSS functions including content(), string(), and leader(), and the three <target> functions target-counter(), target-counters(), and target-text().

Data types

• <content-list>
• <content-replacement> (see {{cssxref("image")}} )
• {{cssxref("image")}} 
• <counter>
• <quote>
• <target>

Guides

• “How to” guide for generated content

  • : Learn how to add text or image content to a document using the {{cssxref("content")}}  property.

• Create fancy boxes with generated content

  • : Example of styling generated content for visual effects.

Related concepts

• CSS pseudo-elements module

  • {{cssxref("::before")}}  pseudo-element
  • {{cssxref("::after")}}  pseudo-element
  • {{cssxref("::marker")}}  pseudo-element

• CSS lists and counters module

  • {{cssxref("counter", "counter()")}}  function
  • {{cssxref("counters", "counters()")}}  function
  • {{cssxref("counter-increment")}}  property
  • {{cssxref("counter-reset")}}  property

• CSS values and units module

  • {{cssxref("attr", "attr()")}}  function
  • {{cssxref("string")}}  data type
  • {{cssxref("image")}}  data type

Specifications

{{Specifications}} 

See also

• CSS pseudo-elements module
• CSS lists and counters module
• Replaced elements