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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html lang=en>
<head profile="http://dublincore.org/documents/2008/08/04/dc-html/ ">
<meta charset=utf8>
<title>Selectors Level 4</title>
<link href="http://purl.org/dc/terms/" rel=schema.dcterms>
<link href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=dcterms.rights>
<meta content="Selectors Level 4" name=dcterms.title>
<meta content=text name=dcterms.type>
<meta content=2013-06-28 name=dcterms.date>
<meta content="Elika J. Etemad" name=dcterms.creator>
<meta content="Tab Atkins Jr." name=dcterms.creator>
<meta content=W3C name=dcterms.publisher>
<meta content="http://dev.w3.org/csswg/selectors4/"
name=dcterms.identifier>
<link href="../default.css" rel=stylesheet type="text/css">
<style type="text/css">
.tprofile td, th { vertical-align: baseline; padding: 0 0.5em; }
.tprofile th { text-align: right; }
</style>
<link href="http://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
type="text/css">
<body>
<div class=head> <!--begin-logo-->
<p><a href="http://www.w3.org/"><img alt=W3C height=48
src="http://www.w3.org/Icons/w3c_home" width=72></a> <!--end-logo-->
<h1 id=title>Selectors Level 4</h1>
<h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 28 June 2013</h2>
<dl>
<dt>This version:
<dd><a href="http://dev.w3.org/csswg/selectors4/">
http://www.w3.org/TR/2013/ED-selectors4-20130628/</a>
<dt>Editor's draft:
<dd><a href="http://dev.w3.org/csswg/selectors4/">
http://dev.w3.org/csswg/selectors4/</a>
<dt>Latest version of Selectors Level 4:
<dd><a href="http://www.w3.org/TR/selectors4/">
http://www.w3.org/TR/selectors4/</a>
<dt>Latest Selectors specification:
<dd><a href="http://www.w3.org/TR/selectors/">
http://www.w3.org/TR/selectors/</a>
<dt>Previous version:
<dd><a href="http://www.w3.org/TR/2011/WD-selectors4-20110929/">
http://www.w3.org/TR/2011/WD-selectors4-20110929/</a>
<dt>Feedback:
<dd><a
href="mailto:www-style@w3.org?subject=%5Bselectors4%5D%20feedback">www-style@w3.org</a>
with subject line “<kbd>[selectors4] <var>… message topic
…</var></kbd>” (<a
href="http://lists.w3.org/Archives/Public/www-style/"
rel=discussion>archives</a>)
<dt>Editors:
<dd class=vcard><a class="url fn"
href="http://fantasai.inkedblade.net/contact">Elika J. Etemad</a>
(Mozilla)
<dd class=vcard> <a class="url fn"
href="http://www.xanthir.com/contact/">Tab Atkins Jr.</a> (<span
class=org>Google</span>)
<dt>Previous Editors:
<dd class=vcard><a class="url fn" href="http://www.tantek.com/"
lang=tr>Tantek Çelik</a> (Microsoft)
<dd class=vcard><span class=fn>Daniel Glazman</span> (Disruptive
Innovations SARL)
<dd class=vcard><span class=fn>Ian Hickson</span> (Opera Softare ASA)
<dd class=vcard><span class=fn>Peter Linss</span> (Netscape/AOL)
<dd class=vcard><span class=fn>John Williams</span> (Quark, Inc.)
</dl>
<!--begin-copyright-->
<p class=copyright><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> © 2013 <a href="http://www.w3.org/"><abbr
title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a
href="http://www.csail.mit.edu/"><abbr
title="Massachusetts Institute of Technology">MIT</abbr></a>, <a
href="http://www.ercim.eu/"><abbr
title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>,
<a href="http://www.keio.ac.jp/">Keio</a>, <a
href="http://ev.buaa.edu.cn/">Beihang</a>), All Rights Reserved. W3C <a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
<a
href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>
and <a
href="http://www.w3.org/Consortium/Legal/copyright-documents">document
use</a> rules apply.</p>
<!--end-copyright-->
<hr title="Separator for header">
</div>
<h2 class="no-num no-toc" id=abstract> Abstract</h2>
<p><a href="#selector"><em>Selectors</em></a> are patterns that match
against elements in a tree, and as such form one of several technologies
that can be used to select nodes in an XML document. Selectors have been
optimized for use with HTML and XML, and are designed to be usable in
performance-critical code. They are a core component of <abbr
title="Cascading Style Sheets">CSS</abbr> (Cascading Style Sheets), which
uses Selectors to bind style properties to elements in the document.
<p>Selectors Level 4 describes the selectors that already exist in <a
href="#SELECT" rel=biblioentry>[SELECT]<!--{{!SELECT}}--></a>, and further
introduces new selectors for CSS and other languages that may need them.
<h2 class="no-num no-toc" id=status>Status of this Document</h2>
<!--begin-status-->
<p>This is a public copy of the editors' draft. It is provided for
discussion only and may change at any moment. Its publication here does
not imply endorsement of its contents by W3C. Don't cite this document
other than as work in progress.
<
9E68
/div>
<p>The (<a
href="http://lists.w3.org/Archives/Public/www-style/">archived</a>) public
mailing list <a
href="mailto:www-style@w3.org?Subject=%5Bselectors4%5D%20PUT%20SUBJECT%20HERE">
www-style@w3.org</a> (see <a
href="http://www.w3.org/Mail/Request">instructions</a>) is preferred for
discussion of this specification. When sending e-mail, please put the text
“selectors4” in the subject, preferably like this:
“[<!---->selectors4<!---->] <em>…summary of comment…</em>”
<p>This document was produced by the <a
href="http://www.w3.org/Style/CSS/members">CSS Working Group</a> (part of
the <a href="http://www.w3.org/Style/">Style Activity</a>).
<p>This document was produced by a group operating under the <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February
2004 W3C Patent Policy</a>. W3C maintains a <a
href="http://www.w3.org/2004/01/pp-impl/32061/status"
rel=disclosure>public list of any patent disclosures</a> made in
connection with the deliverables of the group; that page also includes
instructions for disclosing a patent. An individual who has actual
knowledge of a patent which the individual believes contains <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
6 of the W3C Patent Policy</a>.</p>
<!--end-status-->
<p>This module is a somewhat-unstable Working Draft. <strong>If you are
looking for a stable Selectors specification, use <a
href="http://www.w3.org/TR/css3-selectors/">Selectors 3</a>.</strong> Read
the <a href="http://www.w3.org/TR/CSS/">CSS Snapshot</a> for an overview
of the CSS development process. See the <a href="#overview">Selectors
Overview</a> for a summary of additions to level 3.
<p>The following features are at-risk and may be dropped during the CR
period if there is not sufficient implementer interest: the reference
combinator, the column combinator, the ‘<code
class=css>:invalid-drop</code>’ and ‘<code
class=css>:valid-drop</code>’ pseudo-classes.
<h2 class="no-num no-toc" id=contents>Table of Contents</h2>
<!--begin-toc-->
<ul class=toc>
<li><a href="#context"><span class=secno>1. </span> Introduction</a>
<ul class=toc>
<li><a href="#placement"><span class=secno>1.1. </span>Module
Interactions</a>
</ul>
<li><a href="#overview"><span class=secno>2. </span> Selectors
Overview</a>
<ul class=toc>
<li><a href="#profiles"><span class=secno>2.1. </span> <i>Fast</i> vs
<i>Complete</i> Selector Profiles</a>
</ul>
<li><a href="#syntax"><span class=secno>3. </span> Selector Syntax and
Structure</a>
<ul class=toc>
<li><a href="#structure"><span class=secno>3.1. </span> Structure and
Terminology</a>
<li><a href="#subject"><span class=secno>3.2. </span> Determining the
Subject of a Selector</a>
<li><a href="#scoping"><span class=secno>3.3. </span> Scoped
Selectors</a>
<li><a href="#relative"><span class=secno>3.4. </span> Relative
Selectors</a>
<ul class=toc>
<li><a href="#absolutizing"><span class=secno>3.4.1. </span>
Absolutizing a Relative Selector</a>
</ul>
<li><a href="#pseudo-classes"><span class=secno>3.5. </span>
Pseudo-classes</a>
<li><a href="#pseudo-elements"><span class=secno>3.6.
</span>Pseudo-elements</a>
<li><a href="#case-sensitive"><span class=secno>3.7. </span> Characters
and case sensitivity</a>
<li><a href="#namespaces"><span class=secno>3.8. </span> Namespaces</a>
<li><a href="#invalid"><span class=secno>3.9. </span> Invalid Selectors
and Error Handling</a>
</ul>
<li><a href="#logical-combination"><span class=secno>4. </span> Logical
Combinations</a>
<ul class=toc>
<li><a href="#grouping"><span class=secno>4.1. </span> Selector
Lists</a>
<li><a href="#matches"><span class=secno>4.2. </span> The Matches-Any
Pseudo-class: <code>:matches()</code></a>
<li><a href="#negation"><span class=secno>4.3. </span> The Negation
Pseudo-class: <code>:not()</code></a>
</ul>
<li><a href="#elemental-selectors"><span class=secno>5. </span> Elemental
selectors</a>
<ul class=toc>
<li><a href="#type-selectors"><span class=secno>5.1. </span> Type (tag
name) selector</a>
<ul class=toc>
<li><a href="#typenmsp"><span class=secno>5.1.1. </span> Type
selectors and namespaces</a>
</ul>
<li><a href="#universal-selector"><span class=secno>5.2. </span>
Universal selector </a>
<ul class=toc>
<li><a href="#univnmsp"><span class=secno>5.2.1. </span> Universal
selector and namespaces</a>
</ul>
</ul>
<li><a href="#attribute-selectors"><span class=secno>6. </span> Attribute
selectors</a>
<ul class=toc>
<li><a href="#attribute-representation"><span class=secno>6.1. </span>
Attribute presence and value selectors</a>
<li><a href="#attribute-substrings"><span class=secno>6.2. </span>
Substring matching attribute selectors</a>
<li><a href="#attribute-case"><span class=secno>6.3. </span>
Case-sensitivity</a>
<li><a href="#attrnmsp"><span class=secno>6.4. </span> Attribute
selectors and namespaces</a>
<li><a href="#def-values"><span class=secno>6.5. </span> Default
attribute values in DTDs</a>
<li><a href="#class-html"><span class=secno>6.6. </span> Class
selectors</a>
<li><a href="#id-selectors"><span class=secno>6.7. </span> ID
selectors</a>
</ul>
<li><a href="#linguistic-pseudos"><span class=secno>7. </span> Linguistic
Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-dir-pseudo"><span class=secno>7.1. </span> The
directionality pseudo-class <code>:dir()</code></a>
<li><a href="#the-lang-pseudo"><span class=secno>7.2. </span> The
language pseudo-class <code>:lang()</code></a>
</ul>
<li><a href="#location"><span class=secno>8. </span> Location
Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-any-link-pseudo"><span class=secno>8.1. </span> The
hyperlink pseudo-class: <code>:any-link</code></a>
<li><a href="#link"><span class=secno>8.2. </span> The link history
pseudo-classes: <code>:link</code> and <code>:visited</code></a>
<li><a href="#local-pseudo"><span class=secno>8.3. </span> The local
link pseudo-class <code>:local-link</code></a>
<li><a href="#the-target-pseudo"><span class=secno>8.4. </span> The
target pseudo-class <code>:target</code></a>
<li><a href="#the-scope-pseudo"><span class=secno>8.5. </span> The
reference element pseudo-class <code>:scope</code></a>
</ul>
<li><a href="#useraction-pseudos"><span class=secno>9. </span> User Action
Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-hover-pseudo"><span class=secno>9.1. </span> The
pointer hover pseudo-class <code>:hover</code></a>
<li><a href="#the-active-pseudo"><span class=secno>9.2. </span> The
activation pseudo-class <code>:active</code></a>
<li><a href="#the-focus-pseudo"><span class=secno>9.3. </span> The input
focus pseudo-class <code>:focus</code></a>
<li><a href="#drag-pseudos"><span class=secno>9.4. </span> The
drag-and-drop pseudo-classes</a>
</ul>
<li><a href="#time-pseudos"><span class=secno>10. </span> Time-dimensional
Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-current-pseudo"><span class=secno>10.1. </span> The
current-element pseudo-class <code>:current</code></a>
<li><a href="#the-past-pseudo"><span class=secno>10.2. </span> The
past-element pseudo-class <code>:past</code></a>
<li><a href="#the-future-pseudo"><span class=secno>10.3. </span> The
future-element pseudo-class <code>:future</code></a>
</ul>
<li><a href="#input-pseudos"><span class=secno>11. </span> The Input
Pseudo-classes</a>
<ul class=toc>
<li><a href="#input-states"><span class=secno>11.1. </span> Input
Control States</a>
<ul class=toc>
<li><a href="#enableddisabled"><span class=secno>11.1.1. </span> The
<code>:enabled</code> and <code>:disabled</code> pseudo-classes</a>
<li><a href="#rw-pseudos"><span class=secno>11.1.2. </span> The
mutability pseudo-classes <code>:read-only</code> and
<code>:read-write</code></a>
<li><a href="#placeholder"><span class=secno>11.1.3. </span> The
placeholder-shown pseudo-class <code>:placeholder-shown</code></a>
<li><a href="#the-default-pseudo"><span class=secno>11.1.4. </span>
The default-option pseudo-class <code>:default</code></a>
</ul>
<li><a href="#input-value-states"><span class=secno>11.2. </span> Input
Value States</a>
<ul class=toc>
<li><a href="#checked"><span class=secno>11.2.1. </span> The
selected-option pseudo-class <code>:checked</code></a>
<li><a href="#indeterminate"><span class=secno>11.2.2. </span> The
indeterminate-value pseudo-class <code>:indeterminate</code></a>
</ul>
<li><a href="#ui-validity"><span class=secno>11.3. </span> Input
Value-checking</a>
<ul class=toc>
<li><a href="#validity-pseudos"><span class=secno>11.3.1. </span> The
validity pseudo-classes: <code>:valid</code> and
<code>:invalid</code></a>
<li><a href="#range-pseudos"><span class=secno>11.3.2. </span> The
range pseudo-classes <code>:in-range</code> and
<code>:out-of-range</code></a>
<li><a href="#opt-pseudos"><span class=secno>11.3.3. </span> The
optionality pseudo-classes <code>:required</code> and
<code>:optional</code></a>
<li><a href="#user-pseudos"><span class=secno>11.3.4. </span> The
user-interaction pseudo-class <code>:user-error</code></a>
</ul>
</ul>
<li><a href="#structural-pseudos"><span class=secno>12. </span>
Tree-Structural pseudo-classes</a>
<ul class=toc>
<li><a href="#the-root-pseudo"><span class=secno>12.1. </span>
<code>:root</code> pseudo-class</a>
<li><a href="#the-empty-pseudo"><span class=secno>12.2. </span>
<code>:empty</code> pseudo-class</a>
<li><a href="#the-blank-pseudo"><span class=secno>12.3. </span>
<code>:blank</code> pseudo-class</a>
<li><a href="#anb"><span class=secno>12.4. </span> Indexed
Pseudo-classes: the <var>An+B</var> micro-syntax</a>
<ul class=toc>
<li><a href="#anb-syntax"><span class=secno>12.4.1. </span> Syntax</a>
<li><a href="#anb-grammar"><span class=secno>12.4.2. </span>
Grammar</a>
</ul>
<li><a href="#child-index"><span class=secno>12.5. </span> Child-indexed
Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-nth-child-pseudo"><span class=secno>12.5.1. </span>
<code>:nth-child()</code> pseudo-class</a>
<li><a href="#the-nth-last-child-pseudo"><span class=secno>12.5.2.
</span> <code>:nth-last-child()</code> pseudo-class</a>
<li><a href="#the-first-child-pseudo"><span class=secno>12.5.3.
</span> <code>:first-child</code> pseudo-class</a>
<li><a href="#the-last-child-pseudo"><span class=secno>12.5.4. </span>
<code>:last-child</code> pseudo-class</a>
<li><a href="#the-only-child-pseudo"><span class=secno>12.5.5. </span>
<code>:only-child</code> pseudo-class</a>
</ul>
<li><a href="#typed-child-index"><span class=secno>12.6. </span> Typed
Child-indexed Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-nth-of-type-pseudo"><span class=secno>12.6.1.
</span> <code>:nth-of-type()</code> pseudo-class</a>
<li><a href="#the-nth-last-of-type-pseudo"><span class=secno>12.6.2.
</span> <code>:nth-last-of-type()</code> pseudo-class</a>
<li><a href="#the-first-of-type-pseudo"><span class=secno>12.6.3.
</span> <code>:first-of-type</code> pseudo-class</a>
<li><a href="#the-last-of-type-pseudo"><span class=secno>12.6.4.
</span> <code>:last-of-type</code> pseudo-class</a>
<li><a href="#the-only-of-type-pseudo"><span class=secno>12.6.5.
</span> <code>:only-of-type</code> pseudo-class</a>
</ul>
<li><a href="#selected-child-index"><span class=secno>12.7. </span>
Selected Child-indexed Pseudo-classes</a>
<ul class=toc>
<li><a href="#the-nth-match-pseudo"><span class=secno>12.7.1. </span>
<code>:nth-match()</code> pseudo-class</a>
<li><a href="#the-nth-last-match-pseudo"><span class=secno>12.7.2.
</span> <code>:nth-last-match()</code> pseudo-class</a>
</ul>
</ul>
<li><a href="#combinators"><span class=secno>13. </span> Combinators</a>
<ul class=toc>
<li><a href="#descendant-combinators"><span class=secno>13.1. </span>
Descendant combinator (<code> </code>)</a>
<li><a href="#child-combinators"><span class=secno>13.2. </span> Child
combinator (<code>></code>)</a>
<li><a href="#adjacent-sibling-combinators"><span class=secno>13.3.
</span> Next-sibling combinator (<code>+</code>)</a>
<li><a href="#general-sibling-combinators"><span class=secno>13.4.
</span> Following-sibling combinator (<code>~</code>)</a>
<li><a href="#idref-combinators"><span class=secno>13.5. </span>
Reference combinators <code>/ref/</code></a>
</ul>
<li><a href="#table-pseudos"><span class=secno>14. </span> Grid-Structural
Selectors</a>
<ul class=toc>
<li><a href="#column-combinator"><span class=secno>14.1. </span> Column
combinator</a>
<li><a href="#the-nth-column-pseudo"><span class=secno>14.2. </span>
<code>:nth-column()</code> pseudo-class</a>
<li><a href="#the-nth-last-column-pseudo"><span class=secno>14.3.
</span> <code>:nth-last-column()</code> pseudo-class</a>
</ul>
<li><a href="#specificity"><span class=secno>15. </span> Calculating a
selector's specificity</a>
<li><a href="#grammar"><span class=secno>16. </span> Grammar</a>
<li><a href="#changes"><span class=secno>17. </span> Changes</a>
<li><a href="#conformance"><span class=secno>18. </span> Conformance</a>
<ul class=toc>
<li><a href="#conventions"><span class=secno>18.1. </span>Document
Conventions</a>
<li><a href="#conformance-classes"><span class=secno>18.2. </span>
Conformance Classes</a>
<li><a href="#partial"><span class=secno>18.3. </span> Partial
Implementations</a>
<li><a href="#experimental"><span class=secno>18.4. </span> Experimental
Implementations</a>
</ul>
<li><a href="#acknowledgements"><span class=secno>19. </span>
Acknowledgements</a>
<li><a href="#references"><span class=secno>20. </span> References</a>
<ul class=toc>
<li><a href="#normative-references"><span class=secno>20.1. </span>
Normative References</a>
<li><a href="#informative-references"><span class=secno>20.2. </span>
Informative References</a>
</ul>
</ul>
<!--end-toc-->
<h2 id=context><span class=secno>1. </span> Introduction</h2>
<p><em>This section is not normative.</em>
<p> A selector is a boolean predicate that takes an element in a tree
structure and tests whether the element matches the selector or not.
<p> These expressions may be used for many things:
<ul>
<li> directly on an element to test whether it matches some criteria, such
as in the <code>Element.matches()</code> function defined in <a
href="#SELECTORS-API2"
rel=biblioentry>[SELECTORS-API2]<!--{{SELECTORS-API2}}--></a>
<li> applied to an entire tree of elements to filter it into a set of
elements that match the criteria, such as in the
<code>document.findAll()</code> function defined in <a
href="#SELECTORS-API2"
rel=biblioentry>[SELECTORS-API2]<!--{{SELECTORS-API2}}--></a> or the
selector of a CSS style rule.
<li> used "in reverse" to generate markup that would match a given
selector, such as in <a href="http://haml.info/">HAML</a> or <a
href="http://en.wikipedia.org/wiki/Zen_Coding">Zen Coding</a>
</ul>
<p> Selectors Levels 1, 2, and 3 are defined as the subsets of selector
functionality defined in the <a
href="http://www.w3.org/TR/REC-CSS1">CSS1</a>, <a
href="http://www.w3.org/TR/CSS21/">CSS2.1</a>, and <a
href="http://www.w3.org/TR/css3-selectors/">Selectors Level 3</a>
specifications, respectively. This module defines Selectors Level 4.
<h3 id=placement><span class=secno>1.1. </span>Module Interactions</h3>
<p>This module replaces the definitions of and extends the set of selectors
defined for CSS in <a href="#SELECT"
rel=biblioentry>[SELECT]<!--{{SELECT}}--></a> and <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{CSS21}}--></a>.
<p> Pseudo-element selectors, which define abstract elements in a rendering
tree, are not part of this specification: their generic syntax is
described here, but, due to their close integration with the rendering
model and irrelevance to other uses such as DOM queries, they will be
defined in other modules.
<h2 id=overview><span class=secno>2. </span> Selectors Overview</h2>
<p><em>This section is non-normative, as it merely summarizes the following
sections.</em>
<p>A Selector represents a structure. This structure can be used as a
condition (e.g. in a CSS rule) that determines which elements a selector
matches in the document tree, or as a flat description of the HTML or XML
fragment corresponding to that structure.
<p>Selectors may range from simple element names to rich contextual
representations.
<p>The following table summarizes the Selector syntax:
<table class=data><col class=pattern><col class=meaning><col
class=section><col class=level>
<thead>
<tr>
<th>Pattern
<th>Represents
<th>Section
<th>Level
<tbody>
<tr>
<td><code>*</code>
<td>any element
<td><a href="#universal-selector">Universal selector</a>
<td>2
<tr>
<td><code>E</code>
<td>an element of type E
<td><a href="#type-selectors">Type (tag name) selector</a>
<td>1
<tbody>
<tr>
<td><code>E:not(<var>s1</var>, <var>s2</var>)</code>
<td>an E element that does not match either <a
href="#compound"><i>compound selector</i></a> <var>s1</var> or <a
href="#compound"><i>compound selector</i></a> <var>s2</var>
<td><a href="#negation">Negation pseudo-class</a>
<td>3/4
<tr>
<td><code>E:matches(<var>s1</var>, <var>s2</var>)</code>
<td>an E element that matches <a href="#compound"><i>compound
selector</i></a> <var>s1</var> and/or <a href="#compound"><i>compound
selector</i></a> <var>s2</var>
<td><a href="#matches">Matches-any pseudo-class</a>
<td>4
<tbody>
<tr>
<td><code>E.warning</code>
<td>an E element belonging to the class <code>warning</code> (the
document language specifies how class is determined).
<td><a href="#class-html">Class selectors</a>
<td>1
<tr>
<td><code>E#myid</code>
<td>an E element with ID equal to <code>myid</code>.
<td><a href="#id-selectors">ID selectors</a>
<td>1
<tr>
<td><code>E[foo]</code>
<td>an E element with a <code>foo</code> attribute
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>2
<tr>
<td><code>E[foo="bar"]</code>
<td>an E element whose <code>foo</code> attribute value is exactly equal
to <code>bar</code>
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>2
<tr>
<td><code>E[foo="bar" i]</code>
<td>an E element whose <code>foo</code> attribute value is exactly equal
to any (ASCII-range) case-permutation of <code>bar</code>
<td><a href="#attribute-case">Attribute selectors: Case-sensitivity</a>
<td>4
<tr>
<td><code>E[foo~="bar"]</code>
<td>an E element whose <code>foo</code> attribute value is a list of
whitespace-separated values, one of which is exactly equal to
<code>bar</code>
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>2
<tr>
<td><code>E[foo^="bar"]</code>
<td>an E element whose <code>foo</code> attribute value begins exactly
with the string "bar"
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>3
<tr>
<td><code>E[foo$="bar"]</code>
<td>an E element whose <code>foo</code> attribute value ends exactly
with the string <code>bar</code>
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>3
<tr>
<td><code>E[foo*="bar"]</code>
<td>an E element whose <code>foo</code> attribute value contains the
substring <code>bar</code>
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>3
<tr>
<td><code>E[foo|="en"]</code>
<td>an E element whose <code>foo</code> attribute value is a
hyphen-separated list of values beginning with <code>en</code>
<td><a href="#attribute-selectors">Attribute selectors</a>
<td>2
<tbody>
<tr>
<td><code>E:dir(ltr)</code>
<td>an element of type E in with left-to-right directionality (the
document language specifies how directionality is determined)
<td><a href="#dir-pseudo">The :dir() pseudo-class</a>
<td>4
<tr>
<td><code>E:lang(zh, *-hant)</code>
<td>an element of type E tagged as being either in Chinese (any dialect
or writing system) or othewise written with traditional Chinese
characters
<td><a href="#lang-pseudo">The :lang() pseudo-class</a>
<td>2/4
<tbody>
<tr>
<td><code>E:any-link</code>
<td>an E element being the source anchor of a hyperlink
<td><a href="#any-link-pseudo">The hyperlink pseudo-class</a>
<td>4
<tr>
<td><code>E:link</code>
<td>an E element being the source anchor of a hyperlink of which the
target is not yet visited
<td><a href="#link">The link history pseudo-classes</a>
<td>1
<tr>
<td><code>E:visited</code>
<td>an E element being the source anchor of a hyperlink of which the
target is already visited
<td><a href="#link">The link history pseudo-classes</a>
<td>1
<tr>
<td><code>E:local-link</code>
<td>an E element being the source anchor of a hyperlink of which the
target is the current document
<td><a href="#local-pseudo">The local link pseudo-class</a>
<td>4
<tr>
<td><code>E:local-link(0)</code>
<td>an E element being the source anchor of a hyperlink of which the
target is within the current domain
<td><a href="#local-pseudo">The local link pseudo-class</a>
<td>4
<tr>
<td><code>E:target</code>
<td>an E element being the target of the referring URL
<td><a href="#target-pseudo">The target pseudo-class</a>
<td>3
<tr>
<td><code>E:scope</code>
<td>an E element being a designated reference element
<td><a href="#scope-pseudo">The scope pseudo-class</a>
<td>4
<tbody>
<tr>
<td><code>E:current</code>
<td>an E element that is currently presented in a time-dimensional
canvas
<td><a href="#time-pseudos">Time-dimensional Pseudo-classes</a>
<td>4
<tr>
<td><code>E:current(<var>s</var>)</code>
<td>an E element that is the deepest <a
href="#current-pseudo"><code>:current</code></a> element that matches
selector <var>s</var>
<td><a href="#time-pseudos">Time-dimensional Pseudo-classes</a>
<td>4
<tr>
<td><code>E:past</code>
<td>an E element that is in the past in a time-dimensional canvas
<td><a href="#time-pseudos">Time-dimensional Pseudo-classes</a>
<td>4
<tr>
<td><code>E:future</code>
<td>an E element that is in the future in a time-dimensional canvas
<td><a href="#time-pseudos">Time-dimensional Pseudo-classes</a>
<td>4
<tbody>
<tr>
<td><code>E:active</code>
<td>an E element that is in an activated state
<td><a href="#useraction-pseudos">The user action pseudo-classes</a>
<td>1
<tr>
<td><code>E:hover</code>
<td>an E element that is under the cursor, or that has a descendant
under the cursor
<td><a href="#useraction-pseudos">The user action pseudo-classes</a>
<td>2
<tr>
<td><code>E:focus</code>
<td>an E element that has user input focus
<td><a href="#useraction-pseudos">The user action pseudo-classes</a>
<td>2
<tr>
<td><code>E:active-drop</code>
<td>an E element that will receive the item currently being dragged
<td><a href="#drag-pseudos">The drag-and-drop pseudo-classes</a>
<td>4
<tr>
<td><code>E:valid-drop</code>
<td>an E element that could receive the item currently being dragged
<td><a href="#drag-pseudos">The drag-and-drop pseudo-classes</a>
<td>4
<tr>
<td><code>E:invalid-drop</code>
<td>an E element that cannot receive the item currently being dragged,
but could receive some other item
<td><a href="#drag-pseudos">The drag-and-drop pseudo-classes</a>
<td>4
<tbody>
<tr>
<td><code>E:enabled<br>
E:disabled</code>
<td>a user interface element E that is enabled or disabled, respectively
<td><a href="#enableddisabled">The :enabled and :disabled
pseudo-classes</a>
<td>3
<tr>
<td><code>E:read-only</code><br>
<code>E:read-write</code>
<td>a user interface element E that
<td><a href="#rw-pseudos">The mutability pseudo-classes</a>
<td>3-UI/4
<tr>
<td><code>E:placeholder-shown</code>
<td>an input control currently showing placeholder text
<td><a href="#rw-pseudos">The placeholder-shown pseudo-class</a>
<td>3-UI/4
<tr>
<td><code>E:default</code>
<td>a user interface element E that
<td><a href="#default-pseudo">The default option pseudo-class
:default</a>
<td>3-UI/4
<tr>
<td><code>E:checked</code>
<td>a user interface element E that is checked/selected (for instance a
radio-button or checkbox)
<td><a href="#checked">The selected-option pseudo-class</a>
<td>3
<tr>
<td><code>E:indeterminate</code>
<td>a user interface element E that is in an indeterminate state
(neither checked nor unchecked)
<td><a href="#indeterminate">The indeterminate-value pseudo-class</a>
<td>4
<tr>
<td><code>E:valid</code><br>
<code>E:invalid</code>
<td>a user-input element E that
You can’t perform that action at this time.