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<!doctype html><html lang="en">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<title>CSS Fonts Module Level 4</title>
<meta content="width=device-width, initial-scale=1" name="viewport">
<meta content="exploring" name="csswg-work-status">
<meta content="ED" name="w3c-status">
<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">
<style>
body, th, td, h1, h2, h3, h4, h5, h6 {
font-family: "myriad-pro", sans-serif !important;
}
a.self-link {
opacity: 0.1;
}
.touch a.self-link {
opacity: 0.5;
}
a.self-link:hover {
color: black;
opacity: 1;
background-color: transparent;
}
.advisement {
margin-top: 4em;
text-align: left;
}
body > p, body > ul, body > p + dl, #example-f839f6c8,
h3#conventions, h3#conformance-classes, h3#partial,
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h3#experimental, h3#testing { font-size: inherit }
}
ul.indexlist { font-size: inherit; }
</style>
</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 Fonts Module Level 4</h1>
<h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft, <time class="dt-updated" datetime="2015-10-30">30 October 2015</time></span></h2>
<div data-fill-with="spec-metadata">
<dl>
<dt>This version:
<dd><a class="u-url" href="https://dev.w3.org/csswg/css-fonts-4/">https://dev.w3.org/csswg/css-fonts-4/</a>
<dt>Feedback:
<dd><span><a href="mailto:www-style@w3.org?subject=%5Bcss-fonts%5D%20YOUR%20TOPIC%20HERE">www-style@w3.org</a> with subject line “<kbd>[css-fonts] <i data-lt="">… message topic …</i></kbd>” (<a href="http://lists.w3.org/Archives/Public/www-style/" rel="discussion">archives</a>)</span>
<dt class="editor">Editor:
<dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:jdaggett@mozilla.com">John Daggett</a> (<span class="p-org org">Mozilla</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> © 2015 <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 specification defines modifications to the existing <a href="https://dev.w3.org/csswg/css-fonts-3/">CSS Fonts 3</a> specification along with additional experimental features.</p>
</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-fonts%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-fonts” in the subject,
preferably like this:
“[css-fonts] <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/2015/Process-20150901/" id="w3c_process_revision">1 September 2015 W3C Process Document</a>. </p>
<p></p>
</div>
<div data-fill-with="at-risk"></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="#introduction"><span class="secno">1</span> <span class="content">Introduction</span></a>
<li><a href="#font-palette-control"><span class="secno">2</span> <span class="content">Controlling font palette colors</span></a>
<li><a href="#expanded-font-weight-scale"><span class="secno">3</span> <span class="content">Expanding the scale of <code>font-weight</code></span></a>
<li><a href="#min-max-font-size"><span class="secno">4</span> <span class="content">Minimum and maximum <code>font-size</code></span></a>
<li><a href="#extended-generics"><span class="secno">5</span> <span class="content">New generic font families</span></a>
<li><a href="#font-synthesis-small-caps"><span class="secno">6</span> <span class="content">New <code>small-caps</code> value for <code>font-synthesis</code></span></a>
<li><a href="#emoji-fallback"><span class="secno">7</span> <span class="content">Font fallback for emoji codepoints</span></a>
<li><a href="#acknowledgments"><span class="secno"></span> <span class="content">Acknowledgments</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-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>
</ul>
</ul>
</div>
<main>
<script src="http://use.typekit.com/xon2bky.js" type="text/javascript"></script>
<script type="text/javascript">try{Typekit.load();}catch(e){}</script>
<p class="advisement"><strong>This document contains ideas and
experiments that may or may not end up in the final version of a CSS
Fonts specification. Implementors are encouraged to ask about the status
of a particular feature listed here on the <code>www-style</code> mailing list.</strong></p>
<h2 class="heading settled" data-level="1" id="introduction"><span class="secno">1. </span><span class="content">Introduction</span><a class="self-link" href="#introduction"></a></h2>
<p>The CSS3 Fonts specification (<a data-link-type="biblio" href="#biblio-css-fonts-3">[CSS-FONTS-3]</a>) describes the basic
controls CSS provides for selecting and using fonts within documents.
The ideas here are additions or modifications to the properties and
rules defined in CSS3 Fonts.</p>
<p></p>
<h2 class="heading settled" data-level="2" id="font-palette-control"><span class="secno">2. </span><span class="content">Controlling font palette colors</span><a class="self-link" href="#font-palette-control"></a></h2>
<div>
Resolved at 2015 Sydney to add font-palette control. <a href="https://lists.w3.org/Archives/Public/www-style/2015Feb/0211.html">Original proposal</a>.
<p>Details: multicolor fonts now exist.
They expose several "palette indexes" that can be given different colors.
They might also expose predefined palettes.
We want to be able to tell the browser to use a predefined palette,
or to provide our own colors for a palette.</p>
<p>Final proposal is:</p>
<ol>
<li data-md="">
<p>Add a <a class="property" data-link-type="propdesc">font-palette</a> property. For now the grammar is just:</p>
<pre class="prod"><a class="production" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value"><integer></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> light <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> dark <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> <<named-palette-color><a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#mult-comma">#</a></named-palette-color></pre>
<p>with <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value"><integer></a> selecting the nth palette in the font,
and <span class="css">light</span> and <span class="css">dark</span> selecting the first palette designated "light" or "dark"
(this is metadata that’s already part of the format).
If there’s any font fallback, the fallback fonts don’t use a palette.</p>
<li data-md="">
<p>Add <span class="css">@palette-entries</span> to <span class="css">@font-feature-values</span>,
with the name of each declaration defining a name for a particular palette color,
and the value being an integer for the index of that palette color. <a class="production css" data-link-type="type"><named-palette-color></a> is <code><a class="production css" data-link-type="type" href="https://drafts.csswg.org/mediaqueries-4/#typedef-ident"><ident></a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-color-3/#valuea-def-color" title="Expands to: indigo | gold | firebrick | indianred | yellow | darkolivegreen | darkseagreen | slategrey | darkslategrey | greenyellow | mediumorchid | silver | papayawhip | dimgray | black | springgreen | crimson | lightsalmon | brown | turquoise | lightseagreen | cyan | transparent | skyblue | gray | darkturquoise | goldenrod | darkgreen | darkviolet | darkgray | lime | lightpink | teal | darkmagenta | lightgoldenrodyellow | lavender | yellowgreen | thistle | violet | navy | dimgrey | orchid | blue | ghostwhite | honeydew | cornflowerblue | maroon | purple | darkkhaki | mediumpurple | cornsilk | red | bisque | burlywood | darkcyan | khaki | wheat | deepskyblue | rebeccapurple | darkred | steelblue | aliceblue | lightslategrey | gainsboro | mediumturquoise | floralwhite | coral | aqua | mediumslateblue | lightcyan | darksalmon | beige | azure | lightsteelblue | oldlace | mediumvioletred | royalblue | olivedrab | sienna | lightcoral | orangered | navajowhite | slategray | palegreen | mistyrose | seashell | mediumspringgreen | fuchsia | chartreuse | blanchedalmond | peru | aquamarine | white | darkslategray | tomato | ivory | dodgerblue | currentcolor | lemonchiffon | lightgreen | orange | forestgreen | darkgrey | olive | mintcream | antiquewhite | cadetblue | moccasin | limegreen | saddlebrown | grey | darkslateblue | lightskyblue | deeppink | plum | lightgrey | darkgoldenrod | slateblue | sandybrown | magenta | tan | rosybrown | pink | lightblue | palevioletred | mediumseagreen | linen | darkorange | powderblue | seagreen | snow | mediumblue | midnightblue | paleturquoise | palegoldenrod | whitesmoke | darkorchid | salmon | lightslategray | lawngreen | chocolate | lightgray | hotpink | lightyellow | lavenderblush | darkblue | mediumaquamarine | green | blueviolet | peachpuff"><color></a></code>.
Any palette colors not given an explicit value default to value of <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-color-4/#propdef-color">color</a> (so by default it just renders solidly with <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-color-4/#propdef-color">color</a> value, as normal).
If a palette color name occurs more than once, the last one wins
(so you can declare a palette in a variable, and override bits as desired).</p>
</ol>
</div>
<h2 class="heading settled" data-level="3" id="expanded-font-weight-scale"><span class="secno">3. </span><span class="content">Expanding the scale of <code>font-weight</code></span><a class="self-link" href="#expanded-font-weight-scale"></a></h2>
<p>Expand the range of weights possible within the <code>font-weight</code> property and <code>font-weight</code> descriptor to include integer values within
the range [1..999]. Define precisely how the font matching algorithm works
when using weights in this range.</p>
<p class="example" id="example-78f7117b"><a class="self-link" href="#example-78f7117b"></a>Example of using new font weights mixed with old ones</p>
<h2 class="heading settled" data-level="4" id="min-max-font-size"><span class="secno">4. </span><span class="content">Minimum and maximum <code>font-size</code></span><a class="self-link" href="#min-max-font-size"></a></h2>
<p>Define new properties to control the minimum and maximum font-size, <code>min-font-size</code> and <code>max-font-size</code>.</p>
<h2 class="heading settled" data-level="5" id="extended-generics"><span class="secno">5. </span><span class="content">New generic font families</span><a class="self-link" href="#extended-generics"></a></h2>
<p>For most languages and scripts, existing generics can be mapped to
something comparable to that script. That’s useful for the web so that
generics like <code>serif</code> and <code>sans-serif</code> map to
something reasonable independent of the language of the content. But
typographic traditions vary widely across the world and many scripts
have a variety of common typeface designs that don’t map cleanly
into these existing generics. In situations where a similar typeface is
used across a wide variety of platforms, it’s useful to extend the set
of predefined CSS generic font families to cover these type styles.</p>
<p>Add new generic font families for:</p>
<ul>
<li><code>system</code> font family representing the default UI font on a given platform
<li><code>emoji</code> font family for emoji characters
<li><code>math</code> font family used for rendering mathematical expressions
<li><code>fangsong</code> font family used for <em>fang song</em> typefaces in Chinese
</ul>
<h2 class="heading settled" data-level="6" id="font-synthesis-small-caps"><span class="secno">6. </span><span class="content">New <code>small-caps</code> value for <code>font-synthesis</code></span><a class="self-link" href="#font-synthesis-small-caps"></a></h2>
<p>Since small capitals are often synthesized for fonts lacking smalls-caps glyphs,
add a <code>small-caps</code> value to the <code>font-synthesis</code> property
to allow small-caps synthesis to be disabled.
(<a href="https://lists.w3.org/Archives/Public/www-style/2015Jul/0463.html">www-style discussion</a>)</p>
<h2 class="heading settled" data-level="7" id="emoji-fallback"><span class="secno">7. </span><span class="content">Font fallback for emoji codepoints</span><a class="self-link" href="#emoji-fallback"></a></h2>
<p>Many codepoints supported by emoji fonts overlap with codepoints supported
by existing fonts. In fallback situations where it’s not clear whether to use
an emoji font or not, UTR51 defines a the default behavior for a given codepoint.</p>
<p class="note" role="note">Authors can explicitly control emoji or text display using selectors.</p>
<p class="example" id="example-9c8073a8"><a class="self-link" href="#example-9c8073a8"></a>Example of author control over emoji/text styles</p>
<h2 class="no-num heading settled" id="acknowledgments"><span class="content">Acknowledgments</span><a class="self-link" href="#acknowledgments"></a></h2>
<script>
if ('ontouchstart' in window || navigator.maxTouchPoints > 0 || navigator.msMaxTouchPoints > 0) {
var el = document.getElementsByTagName("html")[0];
el.className += " touch";
}
</script>
</main>
<h2 class="no-ref no-num heading settled" id="conformance"><span class="content"> Conformance</span><a class="self-link" href="#conformance"></a></h2>
<h3 class="no-ref heading settled" id="conventions"><span class="content"> Document conventions</span><a class="self-link" href="#conventions"></a></h3>
<p>Conformance requirements are expressed with a combination of
descriptive assertions and RFC 2119 terminology. The key words "MUST",
"MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT",
"RECOMMENDED", "MAY", and "OPTIONAL" in the normative parts of this
document are to be interpreted as described in RFC 2119.
However, for readability, these words do not appear in all uppercase
letters in this specification. </p>
<p>All of the text of this specification is normative except sections
explicitly marked as non-normative, examples, and notes. <a data-link-type="biblio" href="#biblio-rfc2119">[RFC2119]</a></p>
<p>Examples in this specification are introduced with the words "for example"
or are set apart from the normative text with <code>class="example"</code>,
like this: </p>
<div class="example" id="example-f839f6c8">
<a class="self-link" href="#example-f839f6c8"></a>
<p>This is an example of an informative example.</p>
</div>
<p>Informative notes begin with the word "Note" and are set apart from the
normative text with <code>class="note"</code>, like this: </p>
<p class="note" role="note">Note, this is an informative note.</p>
<p>Advisements are normative sections styled to evoke special attention and are
set apart from other normative text with <code><strong class="advisement"></code>, like
this: <strong class="advisement"> UAs MUST provide an accessible alternative. </strong> </p>
<h3 class="no-ref heading settled" id="conformance-classes"><span class="content"> Conformance classes</span><a class="self-link" href="#conformance-classes"></a></h3>
<p>Conformance to this specification
is defined for three conformance classes: </p>
<dl>
<dt>style sheet
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#style-sheet">CSS
style sheet</a>.
<dt>renderer
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a> that interprets the semantics of a style sheet and renders
documents that use them.
<dt>authoring tool
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a> that writes a style sheet.
</dl>
<p>A style sheet is conformant to this specification
if all of its statements that use syntax defined in this module are valid
according to the generic CSS grammar and the individual grammars of each
feature defined in this module. </p>
<p>A renderer is conformant to this specification
if, in addition to interpreting the style sheet as defined by the
appropriate specifications, it supports all the features defined
by this specification by parsing them correctly
and rendering the document accordingly. However, the inability of a
UA to correctly render a document due to limitations of the device
does not make the UA non-conformant. (For example, a UA is not
required to render color on a monochrome monitor.) </p>
<p>An authoring tool is conformant to this specification
if it writes style sheets that are syntactically correct according to the
generic CSS grammar and the individual grammars of each feature in
this module, and meet all other conformance requirements of style sheets
as described in this module. </p>
<h3 class="no-ref heading settled" id="partial"><span class="content"> Partial implementations</span><a class="self-link" href="#partial"></a></h3>
<p>So that authors can exploit the forward-compatible parsing rules to
assign fallback values, CSS renderers <strong>must</strong> treat as invalid (and <a href="http://www.w3.org/TR/CSS21/conform.html#ignore">ignore
as appropriate</a>) any at-rules, properties, property values, keywords,
and other syntactic constructs for which they have no usable level of
support. In particular, user agents <strong>must not</strong> selectively
ignore unsupported component values and honor supported values in a single
multi-value property declaration: if any value is considered invalid
(as unsupported values must be), CSS requires that the entire declaration
be ignored.</p>
<h3 class="no-ref heading settled" id="experimental"><span class="content"> Experimental implementations</span><a class="self-link" href="#experimental"></a></h3>
<p>To avoid clashes with future CSS features, the CSS2.1 specification
reserves a <a href="http://www.w3.org/TR/CSS21/syndata.html#vendor-keywords">prefixed
syntax</a> for proprietary and experimental extensions to CSS. </p>
<p>Prior to a specification reaching the Candidate Recommendation stage
in the W3C process, all implementations of a CSS feature are considered
experimental. The CSS Working Group recommends that implementations
use a vendor-prefixed syntax for such features, including those in
W3C Working Drafts. This avoids incompatibilities with future changes
in the draft. </p>
<h3 class="no-ref heading settled" id="testing"><span class="content"> Non-experimental implementations</span><a class="self-link" href="#testing"></a></h3>
<p>Once a specification reaches the Candidate Recommendation stage,
non-experimental implementations are possible, and implementors should
release an unprefixed implementation of any CR-level feature they
can demonstrate to be correctly implemented according to spec. </p>
<p>To establish and maintain the interoperability of CSS across
implementations, the CSS Working Group requests that non-experimental
CSS renderers submit an implementation report (and, if necessary, the
testcases used for that implementation report) to the W3C before
releasing an unprefixed implementation of any CSS features. Testcases
submitted to W3C are subject to review and correction by the CSS
Working Group. </p>
<p>Further information on submitting testcases and implementation reports
can be found from on the CSS Working Group’s website at <a href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
Questions should be directed to the <a href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a> mailing list. </p>
<h2 class="no-num heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
<h3 class="no-num heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
<ul class="indexlist">
<li>
<a data-link-type="biblio" href="#biblio-css-color-3">[css-color-3]</a> defines the following terms:
<ul>
<li><a href="https://drafts.csswg.org/css-color-3/#valuea-def-color"><color></a>
</ul>
<li>
<a data-link-type="biblio" href="#biblio-css-color-4">[css-color-4]</a> defines the following terms:
<ul>
<li><a href="https://drafts.csswg.org/css-color-4/#propdef-color">color</a>
</ul>
<li>
<a data-link-type="biblio" href="#biblio-css-values-3">[css-values]</a> defines the following terms:
<ul>
<li><a href="https://drafts.csswg.org/css-values-3/#mult-comma">#</a>
<li><a href="https://drafts.csswg.org/css-values-3/#integer-value"><integer></a>
<li><a href="https://drafts.csswg.org/css-values-3/#comb-one">|</a>
</ul>
<li>
<a data-link-type="biblio" href="#biblio-mediaqueries-4">[mediaqueries-4]</a> defines the following terms:
<ul>
<li><a href="https://drafts.csswg.org/mediaqueries-4/#typedef-ident"><ident></a>
</ul>
</ul>
<h2 class="no-num heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
<h3 class="no-num heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
<dl>
<dt id="biblio-css-color-3"><a class="self-link" href="#biblio-css-color-3"></a>[CSS-COLOR-3]
<dd>CSS Color Module Level 3 URL: <a href="http://www.w3.org/TR/css3-color/">http://www.w3.org/TR/css3-color/</a>
<dt id="biblio-css-color-4"><a class="self-link" href="#biblio-css-color-4"></a>[CSS-COLOR-4]
<dd>CSS Color Module Level 4 URL: <a href="https://drafts.csswg.org/css-color-4/">https://drafts.csswg.org/css-color-4/</a>
<dt id="biblio-css-fonts-3"><a class="self-link" href="#biblio-css-fonts-3"></a>[CSS-FONTS-3]
<dd>John Daggett. <a href="http://www.w3.org/TR/css-fonts-3/">CSS Fonts Module Level 3</a>. 3 October 2013. CR. URL: <a href="http://www.w3.org/TR/css-fonts-3/">http://www.w3.org/TR/css-fonts-3/</a>
<dt id="biblio-css-values"><a class="self-link" href="#biblio-css-values"></a>[CSS-VALUES]
<dd>Tab Atkins Jr.; Elika Etemad. <a href="http://www.w3.org/TR/css-values/">CSS Values and Units Module Level 3</a>. 11 June 2015. CR. URL: <a href="http://www.w3.org/TR/css-values/">http://www.w3.org/TR/css-values/</a>
<dt id="biblio-mediaqueries-4"><a class="self-link" href="#biblio-mediaqueries-4"></a>[MEDIAQUERIES-4]
<dd>Florian Rivoal; Tab Atkins Jr.. <a href="http://www.w3.org/TR/mediaqueries-4/">Media Queries Level 4</a>. 5 June 2014. WD. URL: <a href="http://www.w3.org/TR/mediaqueries-4/">http://www.w3.org/TR/mediaqueries-4/</a>
<dt id="biblio-rfc2119"><a class="self-link" href="#biblio-rfc2119"></a>[RFC2119]
<dd>S. Bradner. <a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>. March 1997. Best Current Practice. URL: <a href="https://tools.ietf.org/html/rfc2119">https://tools.ietf.org/html/rfc2119</a>
</dl>
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