files/pt-pt/web/css/pseudo-elements/index.html


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---
title: Pseudoelementos
slug: Web/CSS/Pseudo-elements
tags:
  - CSS
  - Pseudoelemento
  - Referencia
  - Resumo
  - Seletores
  - Sinopse
translation_of: Web/CSS/Pseudo-elements
original_slug: Web/CSS/Pseudoelementos
---
<div>{{CSSRef}}</div>

<p>Um <strong>pseudoelemento</strong> de CSS é uma palavra-chave adicionada ao seletor que lhe permite estilizar uma parte específica do(s) elemento(s) selecionado(s). Por exemplo, {{CSSxRef("::first-line")}} pode ser utilizado para alterar o tipo de letra da primeira linha de um parágrafo.</p>

<pre class="brush: css no-line-numbers">/* The first line of every &lt;p&gt; element. */
p::first-line {
  color: blue;
  text-transform: uppercase;
}</pre>

<div class="note">
<p><strong>Nota:</strong> In contrast to pseudo-elements, {{CSSxRef("pseudo-classes")}} can be used to style an element based on its <em>state</em>.</p>
</div>

<h2 id="Sintaxe">Sintaxe</h2>

<pre class="syntaxbox">selector::pseudo-element {
  property: value;
}</pre>

<p>You can use only one pseudo-element in a selector. It must appear after the simple selectors in the statement.</p>

<div class="note">
<p><strong>Note:</strong> As a rule, double colons (<code>::</code>) should be used instead of a single colon (<code>:</code>). This distinguishes pseudo-classes from pseudo-elements. However, since this distinction was not present in older versions of the W3C spec, most browsers support both syntaxes for the original pseudo-elements.</p>
</div>

<h2 id="Índice_de_pseudoelementos_padrões">Índice de pseudoelementos padrões</h2>

<div class="index" id="index">
<ul>
 <li>{{CSSxRef("::after", "::after (:after)")}}</li>
 <li>{{CSSxRef("::backdrop")}} {{Experimental_Inline}}</li>
 <li>{{CSSxRef("::before", "::before (:before)")}}</li>
 <li>{{CSSxRef("::cue", "::cue (:cue)")}}</li>
 <li>{{CSSxRef("::first-letter", "::first-letter (:first-letter)")}}</li>
 <li>{{CSSxRef("::first-line", "::first-line (:first-line)")}}</li>
 <li>{{CSSxRef("::grammar-error")}} {{Experimental_Inline}}</li>
 <li>{{CSSxRef("::marker")}} {{Experimental_Inline}}</li>
 <li>{{CSSxRef("::placeholder")}} {{Experimental_Inline}}</li>
 <li>{{CSSxRef("::selection")}}</li>
 <li>{{CSSxRef("::slotted", "::slotted()")}}</li>
 <li>{{CSSxRef("::spelling-error")}} {{Experimental_Inline}}</li>
</ul>
</div>

<table class="standard-table">
 <tbody>
  <tr>
   <th>Navegador</th>
   <th>Versão Mais Baixa</th>
   <th>Suporta</th>
  </tr>
  <tr>
   <td rowspan="2">Internet Explorer</td>
   <td>8.0</td>
   <td><code>:pseudo-element</code></td>
  </tr>
  <tr>
   <td>9.0</td>
   <td><code>:pseudo-element ::pseudo-element</code></td>
  </tr>
  <tr>
   <td rowspan="2">Firefox (Gecko)</td>
   <td>1.0 (1.0)</td>
   <td><code>:pseudo-element</code></td>
  </tr>
  <tr>
   <td>1.0 (1.5)</td>
   <td><code>:pseudo-element ::pseudo-element</code></td>
  </tr>
  <tr>
   <td rowspan="2">Opera</td>
   <td>4.0</td>
   <td><code>:pseudo-element</code></td>
  </tr>
  <tr>
   <td>7.0</td>
   <td><code>:pseudo-element ::pseudo-element</code></td>
  </tr>
  <tr>
   <td>Safari (WebKit)</td>
   <td>1.0 (85)</td>
   <td><code>:pseudo-element ::pseudo-element</code></td>
  </tr>
 </tbody>
</table>

<h2 id="Consultar_também">Consultar também:</h2>

<ul>
 <li><a href="/en-US/docs/Web/CSS/Pseudo-classes" style="white-space: nowrap;">Pseudoclasses</a></li>
</ul>