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<!doctype html>
<html lang="en">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<title>CSS Text Decoration Module Level 3</title>
<link href="../default.css" rel="stylesheet" type="text/css">
<link href="../csslogo.ico" rel="shortcut icon" type="image/x-icon">
<style>
body {
background: url("https://www.w3.org/StyleSheets/TR/logo-ED") top left no-repeat white;
background-attachment: fixed;
color: black;
font-family: sans-serif;
margin: 0 auto;
max-width: 50em;
padding: 2em 1em 2em 70px;
}
:link { color: #00C; background: transparent }
:visited { color: #609; background: transparent }
a[href]:active { color: #C00; background: transparent }
a[href]:hover { background: #ffa }
a[href] img { border-style: none }
h1, h2, h3, h4, h5, h6 { text-align: left }
h1, h2, h3 { color: #005A9C; }
h1 { font: 170% sans-serif }
h2 { font: 140% sans-serif }
h3 { font: 120% sans-serif }
h4 { font: bold 100% sans-serif }
h5 { font: italic 100% sans-serif }
h6 { font: small-caps 100% sans-serif }
.hide { display: none }
div.head { margin-bottom: 1em }
div.head h1 { margin-top: 2em; clear: both }
div.head table { margin-left: 2em; margin-top: 2em }
p.copyright { font-size: small }
p.copyright small { font-size: small }
pre { margin-left: 2em }
dt { font-weight: bold }
ul.toc, ol.toc {
list-style: none;
}
</style>
<meta content="Bikeshed 1.0.0" name="generator">
<script defer="" src="//test.csswg.org/harness/annotate.js#css-text-decor-3_dev/css-text-decor-3" type="text/javascript"></script>
</head>
<body class="h-entry">
<div class="head">
<p data-fill-with="logo"><a class="logo" href="http://www.w3.org/">
<img alt="W3C" height="48" src="https://www.w3.org/Icons/w3c_home" width="72">
</a>
</p>
<h1 class="p-name no-ref" id="title">CSS Text Decoration Module Level 3</h1>
<h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft,
<time class="dt-updated" datetime="2014-03-20">20 March 2014</time></span></h2>
<div data-fill-with="spec-metadata">
<dl>
<dt>This version:
<dd><a class="u-url" href="http://dev.w3.org/csswg/css-text-decor-3/">http://dev.w3.org/csswg/css-text-decor-3/</a>
<dt>Latest version:
<dd><a href="http://www.w3.org/TR/css-text-decor-3/">http://www.w3.org/TR/css-text-decor-3/</a>
<dt>Previous Versions:
<dd><a href="http://www.w3.org/TR/2012/WD-css-text-decor-3-20121113/" rel="previous">http://www.w3.org/TR/2012/WD-css-text-decor-3-20121113/</a>
<dt>Feedback:
<dd><span><a href="mailto:www-style@w3.org?subject=%5Bcss-text-decor%5D%20feedback">www-style@w3.org</a> with subject line “<kbd>[css-text-decor] <var>… message topic …</var></kbd>” (<a href="http://lists.w3.org/Archives/Public/www-style/" rel="discussion">archives</a>)</span>
<dt>Test Suite:
<dd><a href="http://test.csswg.org/suites/css-text-decor-3_dev/nightly-unstable/">http://test.csswg.org/suites/css-text-decor-3_dev/nightly-unstable/</a>
<dt>Issue Tracking:
<dd><a href="#issues-index">Inline In Spec</a>
<dd><span><a href="http://www.w3.org/Style/CSS/Tracker/products/10">http://www.w3.org/Style/CSS/Tracker/products/10</a></span>
<dt class="editor">Editors:
<dd class="editor p-author h-card vcard"><a class="p-name fn u-url url" href="http://fantasai.inkedblade.net/contact">fantasai</a> (<span class="p-org org">Invited Expert</span>)
<dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:kojiishi@gluesoft.co.jp">Koji Ishii</a> (<span class="p-org org">Invited Expert</span>)
</dl>
</div>
<div data-fill-with="warning"></div>
<p class="copyright" data-fill-with="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2014 <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>). 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>
<hr title="Separator for header">
</div>
<h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
<div class="p-summary" data-fill-with="abstract">
<p>This module contains the features of CSS relating to text decoration, such as underlines, text shadows, and emphasis marks.</p>
<a href="http://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, in speech, etc.</div>
<h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
<div data-fill-with="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.
</p>
<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=%5Bcss-text-decor%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 “css-text-decor” in the subject,
preferably like this:
“[css-text-decor] <em>…summary of comment…</em>”
</p>
<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>
<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>
<p>
This document is governed by the <a href="http://www.w3.org/2014/Process-20140801/" id="w3c_process_revision">1 August 2014 W3C Process Document</a>.
</p>
<p>
</p></div>
<div data-fill-with="at-risk">
<p>The following features are at-risk, and may be dropped during the CR period:
</p>
<ul>
<li>The <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-skip">text-decoration-skip</a> property.
<li>The line positioning rules.
<li>The ability to place both emphasis marks and ruby above the same base text.
</ul></div>
<h2 class="no-num no-toc no-ref heading settled" id="contents"><span class="content">Table of Contents</span></h2>
<div data-fill-with="table-of-contents" role="navigation">
<ul class="toc" role="directory">
<li><a href="#intro"><span class="secno">1</span> <span class="content">
Introduction</span></a>
<ul class="toc">
<li><a href="#placement"><span class="secno">1.1</span> <span class="content">
Module Interactions</span></a>
<li><a href="#values"><span class="secno">1.2</span> <span class="content">
Values</span></a>
<li><a href="#terms"><span class="secno">1.3</span> <span class="content">Terminology</span></a>
</ul>
<li><a href="#line-decoration"><span class="secno">2</span> <span class="content">
Line Decoration: Underline, Overline, and Strike-Through</span></a>
<ul class="toc">
<li><a href="#text-decoration-line-property"><span class="secno">2.1</span> <span class="content">
Text Decoration Lines: the <span class="property">text-decoration-line</span> property</span></a>
<li><a href="#text-decoration-color-property"><span class="secno">2.2</span> <span class="content">
Text Decoration Color: the <span class="property">text-decoration-color</span> property</span></a>
<li><a href="#text-decoration-style-property"><span class="secno">2.3</span> <span class="content">
Text Decoration Style: the <span class="property">text-decoration-style</span> property</span></a>
<li><a href="#text-decoration-property"><span class="secno">2.4</span> <span class="content">
Text Decoration Shorthand: the <span class="property">text-decoration</span> property</span></a>
<li><a href="#text-decoration-skip-property"><span class="secno">2.5</span> <span class="content">
Text Decoration Line Continuity: the <span class="property">text-decoration-skip</span> property</span></a>
<li><a href="#text-underline-position-property"><span class="secno">2.6</span> <span class="content">
Text Underline Position: the <span class="property">text-underline-position</span> property</span></a>
</ul>
<li><a href="#emphasis-marks"><span class="secno">3</span> <span class="content">
Emphasis Marks</span></a>
<ul class="toc">
<li><a href="#text-emphasis-style-property"><span class="secno">3.1</span> <span class="content">
Emphasis Mark Style: the <span class="property">text-emphasis-style</span> property</span></a>
<li><a href="#text-emphasis-color-property"><span class="secno">3.2</span> <span class="content">
Emphasis Mark Color: the <span class="property">text-emphasis-color</span> property</span></a>
<li><a href="#text-emphasis-property"><span class="secno">3.3</span> <span class="content">
Emphasis Mark Shorthand: the <span class="property">text-emphasis</span> property</span></a>
<li><a href="#text-emphasis-position-property"><span class="secno">3.4</span> <span class="content">
Emphasis Mark Position: the <span class="property">text-emphasis-position</span> property</span></a>
</ul>
<li><a href="#text-shadow-property"><span class="secno">4</span> <span class="content">
Text Shadows: the <span class="property">text-shadow</span> property</span></a>
<li><a href="#painting-order"><span class="secno">5</span> <span class="content">
Painting Order of Text Decorations</span></a>
<li><a href="#acknowledgements"><span class="secno"></span> <span class="content">
Appendix A: Acknowledgements</span></a>
<li><a href="#changes"><span class="secno"></span> <span class="content">Appendix B:
Changes</span></a>
<ul class="toc">
<li><a href="#recent-changes"><span class="secno"></span> <span class="content">
Changes since the <span>January 2013 Last Call Working Draft</span></span></a>
</ul>
<li><a href="#default-stylesheet"><span class="secno"></span> <span class="content">
Appendix C: Default UA Stylesheet</span></a>
<li><a href="#conformance"><span class="secno"></span> <span class="content">
Conformance</span></a>
<ul class="toc">
<li><a href="#conventions"><span class="secno"></span> <span class="content">
Document conventions</span></a>
<li><a href="#conformance-classes"><span class="secno"></span> <span class="content">
Conformance classes</span></a>
<li><a href="#partial"><span class="secno"></span> <span class="content">
Partial implementations</span></a>
<li><a href="#experimental"><span class="secno"></span> <span class="content">
Experimental implementations</span></a>
<li><a href="#testing"><span class="secno"></span> <span class="content">
Non-experimental implementations</span></a>
</ul>
<li><a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
<ul class="toc">
<li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
<li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
</ul>
<li><a href="#references"><span class="secno"></span> <span class="content">References</span></a>
<ul class="toc">
<li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
<li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
</ul>
<li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
<li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
</ul></div>
<main>
<h2 class="heading settled" data-level="1" id="intro"><span class="secno">1. </span><span class="content">
Introduction</span><a class="self-link" href="#intro"></a></h2>
<p><em>This subsection is non-normative.</em>
</p>
<p>This module covers text decoration, i.e. decorating the glyphs
of the text once typeset according to font and typographic rules.
(See <a data-link-type="biblio" href="#biblio-css3text">[CSS3TEXT]</a> and <a data-link-type="biblio" href="#biblio-css3-fonts">[CSS3-FONTS]</a>.)
Such features are traditionally used not only for purely decorative purposes,
but also in some cases to show emphasis, for honorifics,
and to indicate editorial changes such as insertions, deletions, and misspellings.
</p>
<p>CSS Levels 1 and 2 only defined very basic <a href="#line-decoration">line decorations</a>
(underlines, overlines, and strike-throughs)
appropriate to Western typographical traditions.
Level 3 of this module adds the ability to change
the color, style, position, and continuity of these decorations,
and also introduces
<a href="#emphasis-marks">emphasis marks</a> (traditionally used in East Asian typography),
and <a href="#text-shadow-property">shadows</a> (which were proposed then deferred from Level 2).
</p>
<h3 class="heading settled" data-level="1.1" id="placement"><span class="secno">1.1. </span><span class="content">
Module Interactions</span><a class="self-link" href="#placement"></a></h3>
<p>This module replaces and extends the text-decorating
features defined in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a> chapter 16.
</p>
<h3 class="heading settled" data-level="1.2" id="values"><span class="secno">1.2. </span><span class="content">
Values</span><a class="self-link" href="#values"></a></h3>
<p>This specification follows the
<a href="http://www.w3.org/TR/CSS21/about.html#property-defs">CSS property
definition conventions</a> from <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>. Value types not defined in
this specification are defined in CSS Level 2 Revision 1 <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>.
Other CSS modules may expand the definitions of these value types: for
example <a data-link-type="biblio" href="#biblio-css3color">[CSS3COLOR]</a>, when combined with this module, expands the
definition of the <color> value type as used in this specification.</p>
<p>In addition to the property-specific values listed in their definitions,
all properties defined in this specification also accept the
<a href="http://www.w3.org/TR/CSS21/cascade.html#value-def-inherit">inherit</a>
keyword as their property value. For readability it has not been repeated
explicitly.
</p>
<h3 class="heading settled" data-level="1.3" id="terms"><span class="secno">1.3. </span><span class="content">Terminology</span><a class="self-link" href="#terms"></a></h3>
<p>The terms <dfn data-dfn-type="dfn" data-noexport="" id="character"><a href="http://www.w3.org/TR/css3-text/#grapheme-cluster">character</a><a class="self-link" href="#character"></a></dfn>,
<dfn data-dfn-type="dfn" data-noexport="" id="letter"><a href="http://www.w3.org/TR/css3-text/#letter">letter</a><a class="self-link" href="#letter"></a></dfn>, and
<dfn data-dfn-type="dfn" data-noexport="" id="content-language"><a href="http://www.w3.org/TR/css3-text/#content-language">content language</a><a class="self-link" href="#content-language"></a></dfn>
as used in this specification are defined in <a data-link-type="biblio" href="#biblio-css3text">[CSS3TEXT]</a>.
Other terminology and concepts used in this specification are defined
in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a> and <a data-link-type="biblio" href="#biblio-css3-writing-modes">[CSS3-WRITING-MODES]</a>.
</p>
<h2 class="heading settled" data-level="2" id="line-decoration"><span class="secno">2. </span><span class="content">
Line Decoration: Underline, Overline, and Strike-Through</span><a class="self-link" href="#line-decoration"></a></h2>
<p>
The following properties describe line decorations that are added to the content of an element.
When specified on or propagated to an inline box,
that box becomes a <dfn data-dfn-type="dfn" data-noexport="" id="decorating-box">decorating box<a class="self-link" href="#decorating-box"></a></dfn> for that decoration,
applying the decoration to all its fragments.
The decoration is then further propagated to any in-flow block-level boxes that split the inline
(see <a href="http://www.w3.org/TR/CSS21/visuren.html#anonymous-block-level">CSS2.1 section 9.2.1.1</a>).
When specified on or propagated to a block container that establishes an inline formatting context,
the decorations are propagated to an anonymous inline box that wraps all the in-flow inline-level children of the block container.
When specified on or propagated to a ruby box,
the decorations are propagated only to the ruby base.
For all other box types,
the decorations are propagated to all in-flow children.
</p>
<p class="note" role="note">
Note that text decorations are not propagated to any out-of-flow descendants,
nor to the contents of atomic inline-level descendants such as inline blocks and inline tables.
They are also not propagated to inline children of inline boxes,
although the decoration is <em>applied</em> to such boxes.
</p>
<p>
By default underlines, overlines, and line-throughs are applied only to non-replaced inline boxes,
and are drawn across all text (including white space, letter spacing, and word spacing).
Atomic inlines, such as images, are not decorated.
The <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-skip">text-decoration-skip</a> property can be used to modify this behavior,
for example allowing atomic inlines to be underlined
or requiring that white space be skipped.
Margins, borders, and padding of the <i>decorating box</i> are always skipped.
</p>
<p>Relatively positioning a descendant moves all text decorations
applied to it along with the descendant’s text; it does not affect
calculation of the decoration’s initial position on that line.
The <a class="property" data-link-type="propdesc" href="http://dev.w3.org/csswg/css2/visufx.html#propdef-visibility">visibility</a> property, <a class="property" data-link-type="propdesc" href="#propdef-text-shadow">text-shadow</a>, filters, and other graphical transformations
likewise affect text decorations as part of the text they’re drawn on,
even if the decorations were specified on an ancestor box,
and do not affect the calculation of their initial positions or thicknesses.
(In the case of line decorations drawn over an atomic inline
or across the margins/borders/padding of a non-replaced inline box,
they are analogously associated with the affected atomic inline / non-replaced inline box
rather than with the <i>decorating box</i>.)
</p>
<div class="example">
<p>In the following style sheet and document fragment:</p>
<pre> blockquote { text-decoration: underline; color: blue; }
em { display: block; }
cite { color: fuchsia; }</pre>
<pre> <blockquote>
<p>
<span>
Help, help!
<em> I am under a hat! </em>
<cite> —GwieF </cite>
</span>
</p>
</blockquote></pre>
<p>...the underlining for the blockquote element is propagated to an
anonymous inline box that surrounds the span element, causing
the text "Help, help!" to be blue, with the blue underlining from
the anonymous inline underneath it, the color being taken from the
blockquote element. The <code><em>text</em></code>
in the em block is also underlined, as it is in an in-flow block to
which the underline is propagated. The final line of text is fuchsia,
but the underline underneath it is still the blue underline from the
anonymous inline element.</p>
<p><img alt="Sample rendering of the above underline example" src="underline-example.png"></p>
<p>This diagram shows the boxes involved in the example above. The
rounded aqua line represents the anonymous inline element wrapping
the inline contents of the paragraph element, the rounded blue line
represents the span element, and the orange lines represent the
blocks.</p>
</div>
<h3 class="heading settled" data-level="2.1" id="text-decoration-line-property"><span class="secno">2.1. </span><span class="content">
Text Decoration Lines: the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-line">text-decoration-line</a> property</span><a class="self-link" href="#text-decoration-line-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-decoration-line">text-decoration-line<a class="self-link" href="#propdef-text-decoration-line"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td>none | [ underline || overline || line-through || blink ]
<tr>
<th>Initial:
<td>none
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>no (but see prose)
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no
</table>
<p>Specifies what line decorations, if any, are added to the element.
Values have the following meanings:</p>
<dl>
<dt><dfn class="css" data-dfn-for="text-decoration-line" data-dfn-type="value" data-export="" id="valdef-text-decoration-line-none">none<a class="self-link" href="#valdef-text-decoration-line-none"></a></dfn>
<dd>Neither produces nor inhibits text decoration.
<dt><dfn class="css" data-dfn-for="text-decoration-line" data-dfn-type="value" data-export="" id="valdef-text-decoration-line-underline">underline<a class="self-link" href="#valdef-text-decoration-line-underline"></a></dfn>
<dd>Each line of text is underlined.
<dt><dfn class="css" data-dfn-for="text-decoration-line" data-dfn-type="value" data-export="" id="valdef-text-decoration-line-overline">overline<a class="self-link" href="#valdef-text-decoration-line-overline"></a></dfn>
<dd>Each line of text has a line over it (i.e. on the opposite
side from an underline).
<dt><dfn class="css" data-dfn-for="text-decoration-line" data-dfn-type="value" data-export="" id="valdef-text-decoration-line-line-through">line-through<a class="self-link" href="#valdef-text-decoration-line-line-through"></a></dfn>
<dd>Each line of text has a line through the middle.
<dt><dfn class="css" data-dfn-for="text-decoration-line" data-dfn-type="value" data-export="" id="valdef-text-decoration-line-blink">blink<a class="self-link" href="#valdef-text-decoration-line-blink"></a></dfn>
<dd>
The text blinks (alternates between visible and invisible).
Conforming user agents may simply not blink the text.
Note that not blinking the text is one technique to satisfy <a href="http://www.w3.org/TR/UAAG/guidelines.html#tech-on-off-blinking-text">checkpoint 3.3 of WAI-UAAG</a>.
This value is <strong>deprecated</strong> in favor of Animations <a data-link-type="biblio" href="#biblio-css3-animations">[CSS3-ANIMATIONS]</a>.
</dl>
<h3 class="heading settled" data-level="2.2" id="text-decoration-color-property"><span class="secno">2.2. </span><span class="content">
Text Decoration Color: the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-color">text-decoration-color</a> property</span><a class="self-link" href="#text-decoration-color-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-decoration-color">text-decoration-color<a class="self-link" href="#propdef-text-decoration-color"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td><a href="http://www.w3.org/TR/css3-color/#color0"><span class="value-inst-color"><color></span></a>
<tr>
<th>Initial:
<td><a href="http://www.w3.org/TR/css3-color/#currentcolor">currentColor</a>
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>the computed color
<tr>
<th>Animatable:
<td>as <a href="http://www.w3.org/TR/css3-transitions/#animtype-color">color</a>
</table>
<p>This property specifies the color of text decoration (underlines
overlines, and line-throughs) set on the element with
<a class="property" data-link-type="propdesc" href="#propdef-text-decoration-line">text-decoration-line</a>.</p>
<p>
The color of text decorations must remain the same on all decorations originating from a given element,
even if descendant boxes have different specified colors.
</p>
<h3 class="heading settled" data-level="2.3" id="text-decoration-style-property"><span class="secno">2.3. </span><span class="content">
Text Decoration Style: the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-style">text-decoration-style</a> property</span><a class="self-link" href="#text-decoration-style-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-decoration-style">text-decoration-style<a class="self-link" href="#propdef-text-decoration-style"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td>solid | double | dotted | dashed | wavy
<tr>
<th>Initial:
<td>solid
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no
</table>
<p>This property specifies the style of the line(s) drawn for
text decoration specified on the element. Values have the
same meaning as for the
<a href="http://www.w3.org/TR/css3-background/#the-border-style">border-style
properties</a> <a data-link-type="biblio" href="#biblio-css3bg">[CSS3BG]</a>. <span class="css">wavy</span> indicates a wavy line.</p>
<p>
The style of text decorations must remain the same on all decorations originating from a given element,
even if descendant boxes have different specified styles.
</p>
<h3 class="heading settled" data-level="2.4" id="text-decoration-property"><span class="secno">2.4. </span><span class="content">
Text Decoration Shorthand: the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration">text-decoration</a> property</span><a class="self-link" href="#text-decoration-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-decoration">text-decoration<a class="self-link" href="#propdef-text-decoration"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td><var><a class="production" data-link-type="propdesc" href="#propdef-text-decoration-line"><‘text-decoration-line’></a></var> ||
<var><a class="production" data-link-type="propdesc" href="#propdef-text-decoration-style"><‘text-decoration-style’></a></var> ||
<var><a class="production" data-link-type="propdesc" href="#propdef-text-decoration-color"><‘text-decoration-color’></a></var>
<tr>
<th>Initial:
<td>none
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>see individual properties
<tr>
<th>Animatable:
<td>see individual properties
</table>
<p>This property is a shorthand for setting <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-line">text-decoration-line</a>,
<a class="property" data-link-type="propdesc" href="#propdef-text-decoration-color">text-decoration-color</a>, and <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-style">text-decoration-style</a> in one declaration.
Omitted values are set to their initial values. A <a class="property" data-link-type="propdesc" href="#propdef-text-decoration">text-decoration</a>
declaration that omits both the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-color">text-decoration-color</a>
and <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-style">text-decoration-style</a> values is backwards-compatible
with CSS Levels 1 and 2.</p>
<div class="example">
<p>The following example underlines unvisited links with a solid blue
underline in CSS1 and CSS2 UAs and a navy dotted underline in CSS3 UAs.</p>
<pre><code>:link {
color: blue;
text-decoration: underline;
text-decoration: navy dotted underline; /* <a href="http://www.w3.org/TR/CSS21/syndata.html#ignore">Ignored</a> in CSS1/CSS2 UAs */
}</code></pre>
</div>
<h3 class="heading settled" data-level="2.5" id="text-decoration-skip-property"><span class="secno">2.5. </span><span class="content">
Text Decoration Line Continuity: the <a class="property" data-link-type="propdesc" href="#propdef-text-decoration-skip">text-decoration-skip</a> property</span><a class="self-link" href="#text-decoration-skip-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-decoration-skip">text-decoration-skip<a class="self-link" href="#propdef-text-decoration-skip"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td>none | [ objects || spaces || ink || edges || box-decoration ]
<tr>
<th>Initial:
<td>objects
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no
</table>
<p>This property specifies what parts of the element’s content
any text decoration affecting the element must skip over. It
controls all text decoration lines drawn by the element
and also any text decoration lines drawn by its ancestors.
Values have the following meanings:</p>
<dl>
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-none">none<a class="self-link" href="#valdef-text-decoration-skip-none"></a></dfn>
<dd>Skip nothing: text-decoration is drawn for all text content
and across atomic inline-level boxes.
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-objects">objects<a class="self-link" href="#valdef-text-decoration-skip-objects"></a></dfn>
<dd>Skip this element (its entire margin box) if it is an atomic inline
(such as an image or inline-block).
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-spaces">spaces<a class="self-link" href="#valdef-text-decoration-skip-spaces"></a></dfn>
<dd>Skip all spacing, i.e. all <i>characters</i> with the Unicode White_Space property <a data-link-type="biblio" href="#biblio-uax44">[UAX44]</a>
and all <a href="http://www.w3.org/TR/css3-text/#word-separator">word separators</a>,
plus any adjacent <a class="property" data-link-type="propdesc" href="http://dev.w3.org/csswg/css-text-3/#propdef-letter-spacing">letter-spacing</a> or <a class="property" data-link-type="propdesc" href="http://dev.w3.org/csswg/css-text-3/#propdef-word-spacing">word-spacing</a>.
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-ink">ink<a class="self-link" href="#valdef-text-decoration-skip-ink"></a></dfn>
<dd>Skip over where glyphs are drawn:
interrupt the decoration line to let the shape of the text show through
where the text decoration would otherwise cross over a glyph.
The UA must skip a small distance to either side of the glyph outline.
<div class="figure">
<p><img alt="An alphabetic underline through Myanmar text skips around descenders and the vertical strokes of combining characters that drop below the alphabetic baseline." src="decoration-skip-ink.png" title="text-decoration-skip: ink">
</p>
<p class="caption"><a class="css" data-link-type="propdesc" href="#propdef-text-decoration-skip">text-decoration-skip: ink</a></p>
</div>
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-edges">edges<a class="self-link" href="#valdef-text-decoration-skip-edges"></a></dfn>
<dd>The UA should place the start and end of the line inwards slightly
(e.g. by half a line thickness)
from the content edge of the <i>decorating box</i> so that,
e.g. two underlined elements side-by-side do not appear to have a single underline.
(This is important in Chinese, where underlining is a form of punctuation.)
<div class="figure">
<p><img alt="An underline below a series of Chinese characters has a gap between two adjacent underlining elements." src="decoration-skip-edges.png" title="text-decoration-skip: edges">
</p>
<p class="caption"><a class="css" data-link-type="propdesc" href="#propdef-text-decoration-skip">text-decoration-skip: edges</a> for <code><u>石井</u><u>艾俐俐</u></code>
</p>
</div>
<dt><dfn class="css" data-dfn-for="text-decoration-skip" data-dfn-type="value" data-export="" id="valdef-text-decoration-skip-box-decoration">box-decoration<a class="self-link" href="#valdef-text-decoration-skip-box-decoration"></a></dfn>
<dd>
Skip over the box’s margin, border, and padding areas.
Note that this only has an effect on decorations imposed by an ancestor;
a <i>decorating box</i> never draws over its own box decoration.
</dl>
<p class="note" role="note">Note that this property inherits and that descendant
elements can have a different setting.</p>
<p class="note" role="note">
Note that CSS 2.1 required skipping margins, borders, and padding always.
In this level, by default only the margins, borders, and padding of the <i>decorating box</i> are skipped.
In the future CSS2.1 may be updated to match this new default.
</p>
<h3 class="heading settled" data-level="2.6" id="text-underline-position-property"><span class="secno">2.6. </span><span class="content">
Text Underline Position: the <a class="property" data-link-type="propdesc" href="#propdef-text-underline-position">text-underline-position</a> property</span><a class="self-link" href="#text-underline-position-property"></a></h3>
<table class="propdef">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-text-underline-position">text-underline-position<a class="self-link" href="#propdef-text-underline-position"></a></dfn>
<tr>
<th><a href="#values">Value</a>:
<td>auto | [ under || [ left | right ] ]
<tr>
<th>Initial:
<td>auto
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no
</table>
<p>This property sets the position of an underline specified on the element.
(It does not affect underlines specified by ancestor elements.)
If <a class="css" data-link-type="maybe" href="#underline-left">left</a> or <a class="css" data-link-type="maybe" href="#underline-right">right</a> is specified alone,
<a class="css" data-link-type="maybe" href="#underline-under">under</a> is also implied.
</p>
<div class="example">
<p>The following example styles modern Chinese, Japanese, and Korean
texts with the appropriate underline positions in both horizontal
and vertical text:
</p>
<pre>:root:lang(ja), [lang|=ja], :root:lang(ko), [lang|=ko] { text-underline-position: under right; }:root:lang(zh), [lang|=zh] { text-underline-position: under left; }</pre>
<p>(Note that these rules are part of the suggested
<a href="#default-stylesheet">default UA style sheet</a>.)
</p>
</div>