only-child

CSS :only-child Pseudo Class

The :only-child pseudo-selector matches an element if it is the only child of its parent.

The element is selected only if its parent has no other children of any type. The :only-child pseudo-class is the same as :first-child, :last-child or :nth-child(), :nth-last-child(), but with a lower specificity.

Version

Version

Selectors Level 4

Selectors Level 3

Syntax

Syntax

:only-child {
  css declarations;
}

Example of the :only-child selector:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      p:only-child {
        background: #1c87c9;
      }
    </style>
  </head>
  <body>
    <h2>:only-child selector example</h2>
    <div>
      <p>Lorem ipsum is simply dumnmy text.</p>
    </div>
    <div>
      <p>Lorem ipsum is simply dummy text.</p>
      <p>Lorem ipsum is simply dummy text.</p>
    </div>
  </body>
</html>

Example of the :only-child selector for the <li> tag:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      ul li {
        list-style-type: square;
      }
      li:only-child {
        color: blue;
        list-style-type: disc;
      }
    </style>
  </head>
  <body>
    <h2>:only-child selector example</h2>
    <ol>
      <li>
        One element
        <ul>
          <li>This list has just one element.</li>
        </ul>
      </li>
      <li>
        Two elements
        <ul>
          <li>This list has two elements.</li>
          <li>This list has two elements.</li>
        </ul>
      </li>
      <li>
        Three elements
        <ul>
          <li>This list has three elements.</li>
          <li>This list has three elements.</li>
          <li>This list has three elements.</li>
        </ul>
      </li>
    </ol>
  </body>
</html>

Example of the :only-child selector for the <em> tag:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      em:only-child {
        background-color: #8ebf42;
      }
    </style>
  </head>
  <body>
    <h2>:only-child selector example</h2>
    <p>This is a <em>paragraph</em>.</p>
    <p>This is a paragraph.</p>
  </body>
</html>

Example of the :only-child selector for the <div> tag:

<!DOCTYPE html>
<html>
  <head>
    <title>Title of the document</title>
    <style>
      div:only-child {
        color: #8ebf42;
        font-weight: bold;
      }
      div {
        display: block;
        margin: 6px;
        padding: 5px;
        outline: 1px solid #1c87c9;
      }
      div div {
        display: inline-block;
      }
    </style>
  </head>
  <body>
    <h2>:only-child selector example</h2>
    <div>
      <div>I am an only child.</div>
    </div>
    <div>
      <div>I am the 1st sibling.</div>
      <div>I am the 2nd sibling.</div>
      <div>
        I am the 3rd sibling,
        <div>but this is an only child.</div>
      </div>
    </div>
  </body>
</html>


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