csswg-drafts/css-module/Overview.html at 6f4e099a36aaa8c2a20689ef443b4ebb10d00c8c · w3c/csswg-drafts · GitHub

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<!DOCTYPE html>

<html lang=en>
 <head>
  <meta content="text/html; charset=utf-8" http-equiv=Content-Type>
  <title>CSS TEMPLATE Module Level N</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="CSS TEMPLATE Module Level N" name=dcterms.title>
  <meta content=text name=dcterms.type>
  <meta content=2014-03-07 name=dcterms.date>
  <meta content="[editor1 name]" name=dcterms.creator>
  <meta content="[editor2 name]" name=dcterms.creator>
  <meta content=W3C name=dcterms.publisher>
  <meta content="http://dev.w3.org/csswg/css-module/"
   name=dcterms.identifier>
  <link href="#contents" rel=contents>
  <link href="#index" rel=index>
  <link href="../default.css" rel=stylesheet type="text/css">
  <link href="../csslogo.ico" rel="shortcut icon" type="image/x-icon">
  <link href="https://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
   type="text/css">
  <style type="text/css">
    /* delete this block when you've cleared out all the .replaceme elements */
    .replaceme {
      border: solid red;
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      margin: 0 0.1em;
      background: yellow;
      color: green;
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    .
E36F
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       content: "FIXME(";
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    }
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       content: ")";
       color: black;
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  </style>

 <body class=h-entry>
  <div class=head> <!--begin-logo-->
   <p><a href="http://www.w3.org/"><img alt=W3C height=48
    src="https://www.w3.org/Icons/w3c_home" width=72></a> <!--end-logo-->

   <h1 class=p-name>CSS TEMPLATE Module Level N</h1>

   <h2 class="no-num no-toc">Editor's Draft <time class=dt-updated
    datetime=20140307> 7 March 2014</time>
    <!-- for HTML4.x doctypes: <span class="dt-updated"><span class="value-title" title="20140307"> 7 March 2014</span></span> --></h2>

   <dl>
    <dt>This version:

    <dd><a class=u-url
     href="http://dev.w3.org/csswg/css-module/">http://dev.w3.org/csswg/css-module/</a>

    <dt>Latest version:

    <dd><a href="http://www.w3.org/TR/css-module/"><var
     class=replaceme>http://www.w3.org/TR/css-module/</var></a>

    <dt>Editor's draft:

    <dd><a
     href="http://dev.w3.org/csswg/css-module/">http://dev.w3.org/csswg/css-module/</a>
     (<a
     href="https://hg.csswg.org/drafts/log/tip/css-module/Overview.src.html">change
     log</a>)

    <dt>Previous version:

    <dd><a href="http://www.w3.org/PreviousVersionURI">
     http://www.w3.org/PreviousVersionURI</a>

    <dt>Issue Tracking:

    <dd><a href="http://www.w3.org/Style/CSS/Tracker/products/FIXME"
     rel=issues>http://www.w3.org/Style/CSS/Tracker/products/FIXME</a>
     <!-- or use the wiki:
    <dd><a rel="issues" href="http://wiki.csswg.org/spec/cssN-FIXME"
           >http://wiki.csswg.org/spec/cssN-FIXME</a></dd>
-->

    <dt>Feedback:

    <dd><a
     href="mailto:www-style@w3.org?subject=%5BSHORTNAME%5D%20feedback">www-style@w3.org</a>
     with subject line “<kbd>[css-module] <var>… message topic
     …</var></kbd>” (<a
     href="http://lists.w3.org/Archives/Public/www-style/"
     rel=discussion>archives</a>)

    <dt>Editors:

    <dd class="p-author h-card vcard"> <a class="p-name fn u-url url"
     href="[editor1 personal URL (opt.)]" rel=author>[editor1 name]</a>, <a
     class="p-org org h-org"
     href="[affiliation/co. home page (opt.)]">[affiliation (opt.)]</a>,
     <span class="u-email email">[email address (opt.)]</span>

    <dd class="p-author h-card vcard"> <span class="p-name fn">[editor2
     name]</span>, <span class="p-org org">[affiliation (opt.)]</span>, <span
     class="u-email email">[email address (opt.)]</span>
   </dl>
   <!--begin-copyright-->
   <p class=copyright><a
    href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
    rel=license>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>), 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> <span class=p-summary> This module contains the features of CSS
   relating to <var class=replaceme>DESCRIBE HERE</var>. </span> <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.

  <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.

  <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-module%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-module” in the subject, preferably like this:
   “[<!---->css-module<!---->] <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>The following features are at risk: …

  <nav id="toc">
  <h2 class="no-num no-toc" id=contents> Table of Contents</h2>
  <!--begin-toc-->

  <ul class=toc>
   <li><a href="#intro"><span class=secno>1. </span> Introduction</a>
    <ul class=toc>
     <li><a href="#placement"><span class=secno>1.1. </span> Module
      interactions</a>

     <li><a href="#values"><span class=secno>1.2. </span> Values</a>
    </ul>

   <li><a href="#sample-topic"><span class=secno>2. </span> Sample
    section</a>
    <ul class=toc>
     <li><a href="#the-display-model"><span class=secno>2.1. </span> Internal
      display model: the ‘<code class=property>display-inside</code>’
      property</a>
    </ul>

   <li><a href="#conformance"><span class=secno>3. </span> Conformance</a>
    <ul class=toc>
     <li><a href="#conventions"><span class=secno>3.1. </span> Document
      conventions</a>

     <li><a href="#conformance-classes"><span class=secno>3.2. </span>
      Conformance classes</a>

     <li><a href="#partial"><span class=secno>3.3. </span> Partial
      implementations</a>

     <li><a href="#experimental"><span class=secno>3.4. </span> Experimental
      implementations</a>

     <li><a href="#testing"><span class=secno>3.5. </span> Non-experimental
      implementations</a>

     <li><a href="#cr-exit-criteria"><span class=secno>3.6. </span> CR exit
      criteria</a>
    </ul>

   <li class=no-num><a href="#acknowledgments"> Acknowledgments</a>

   <li class=no-num><a href="#references"> References</a>
    <ul class=toc>
     <li class=no-num><a href="#normative-references"> Normative
      references</a>

     <li class=no-num><a href="#other-references"> Other references</a>
    </ul>

   <li class=no-num><a href="#index"> Index</a>

   <li class=no-num><a href="#property-index"> Property index</a>
  </ul>
  <!--end-toc-->
  </nav>

  <h2 id=intro><span class=secno>1. </span> Introduction</h2>

  <p><em>This section is not normative.</em>

  <p><var class=replaceme>Provide background, motivation, etc.</var>

  <h3 id=placement><span class=secno>1.1. </span> Module interactions</h3>

  <p class=replaceme>Explain, normatively, how this module affects the
   definition of CSS.

  <p>This module replaces and extends the <var class=replaceme>SUMMARIZE
   HERE</var> features defined in <a
   href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a> sections <var
   class=replaceme>W.X and Y.Z</var>.

  <p class=replaceme>All properties in this module apply to the
   <code>::first-line</code> and <code>::first-letter</code> pseudo-elements.
   <!-- HANDLE, THEN REMOVE THIS COMMENT
     Properties that affect box layout should be excluded from ::first-line.
     Properties that take things out-of-flow or alter box construction should
     be excluded from both ::first-line and ::first-letter. (A special exception
     is made for float on ::first-letter, which is defined to emulate drop-caps.)
     Examples of ::first-line / ::first-letter statements:
     http://dev.w3.org/csswg/css3-background/#placement
       (All properties apply to ::first-letter; some apply to ::first-line)
  -->

  <h3 id=values><span class=secno>1.2. </span> Values</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
   href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a>. Value types not defined in
   this specification are defined in CSS Level 2 Revision 1 <a
   href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a>. Other CSS modules may
   expand the definitions of these value types: for example <a
   href="#ref-CSS3VAL">[CSS3VAL]<!--{{CSS3VAL}}--></a>, when combined with
   this module, expands the definition of the <var>&lt;length&gt;</var> value
   type as used in this specification.

  <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.

  <h2 id=sample-topic><span class=secno>2. </span> Sample section</h2>

  <p>Look at the mark-up in this section for examples. See the <a
   href="https://www.w3.org/Style/Group/css3-src/bin/README">documentation</a>
   for more precise instructions. The companion of this template shows the <a
   href=Overview.html>processed result</a>.

  <p>To refer to HTML, use <a
   href="#ref-HTML40">[HTML40]<!--{{HTML40}}--></a> (note the double square
   brackets). To make a normative reference, insert a “!”, like this: <a
   href="#ref-CSS3SYN">[CSS3SYN]<!--{{!CSS3SYN}}--></a> The currently
   available <a href="http://dev.w3.org/CSS/biblio/biblio.ref">list of
   bibliographic data</a> can of course be extended.

  <p>We write about a property such as ‘<code
   class=property>display-model</code>’ like this and about a piece of CSS
   code like this: ‘<code class=css>foo: bar</code>’. Inline HTML and XML
   are similar, but use the CODE element: <code
   class=html>&lt;blockquote&gt;...&lt;/blockquote&gt;</code> and <code
   class=xml>&lt;r:xyz&gt;...&lt;/r:xyz&gt;</code>.

  <p class=note>Note that the property will automatically be linked to its
   definition.

  <p>To put <span class=index id=terms>terms</span> into the <span
   class=index-def id=index0>index</span>, there are many <span class=index
   id=variants title=variant>variants</span>, but hopefully the <span
   class=index id=simplest title="simple|simpler|simplest">simplest</span>
   will be the most <span class=index id=common
   title="frequency::common">common</span>. But a little more <span
   class=index id=work title="work|resource::time spent">work</span> now will
   help many people for a long time.

  <p class=note>Note that you can add non-normative notes like this.

  <p>Of course, multi-paragraph notes are also possible: just enclose them in
   a DIV:

  <div class=note>
   <p>Note that this note is a multi-paragraph note.

   <p>It doesn't <em>need</em> to have two paragraphs, but it could.
  </div>

  <p>Displayed examples come in eight different types: CSS examples that need
   no separate paragraph of explanation are put in a simple PRE:

  <pre class=example>EM { font-style: italic }</pre>

  <p>CSS examples that need extra text need a DIV.

  <div class=example>
   <p>The following example is the same as the previous one, but now it is
    explained:

   <pre>EM { font-style: italic }</pre>
  </div>

  <p>Illegal CSS examples (examples of errors) are the same, but with class
   "illegal example". Examples of HTML and XML code have class "html" and
   "xml" respectively, but are otherwise ditto.

  <p>A formal definition of a property looks like this:

  <h3 id=the-display-model><span class=secno>2.1. </span> Internal display
   model: the ‘<a href="#display-inside"><code
   class=property>display-inside</code></a>’ property</h3>

  <table class=propdef>
   <tbody>
    <tr>
     <th>Name:

     <td><dfn id=display-inside>display-inside</dfn>

    <tr>
     <th><a href="#values">Value</a>:

     <td>inline-inside | block-inside | table | ruby | icon

    <tr>
     <th>Initial:

     <td>text

    <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>specified value

    <tr>
     <th>Animatable:

     <td>no

    <tr>
     <th>Canonical order:

     <td><abbr title="follows order of property value definition">per
      grammar</abbr>
  </table>

  <dl>
   <dt><dfn id=value-name>‘<code class=css>value-name</code>’</dfn>

   <dd>Define values using a DL
  </dl>

  <p><dfn id=cross-references>Cross-references</dfn> are created by enclosing
   a term or phrase in &lt;dfn&gt; (like the word <a
   href="#cross-references"><em>cross-references</em></a> earlier in this
   sentence). Then any element with the same content will automatically be
   linked. For example: <a href="#cross-references">cross-references</a>.

  <p>And a figure with a caption is done like this:

  <div class=figure>
   <p><img
    alt="A table with a caption above it; both have margins and the margins between them are collapsed, as is normal for vertical margins."
    src=corner.png>

   <p class=caption>Just a random image. SVG would be nice, but maybe SVG
    isn't sufficiently easy to use yet. W3C prefers PNG over GIF (obviously,
    since PNG is a W3C Rec).
  </div>

  <p>Don't forget to write the longdesc.

  <p class=issue>An open issue or editorial remark is OK in a WD, but they
   should be resolved/removed before the document goes to “CR” (Candidate
   Recommendation). Use class=“issue”.

  <h2 id=conformance><span class=secno>3. </span> Conformance</h2>

  <h3 id=conventions><span class=secno>3.1. </span> Document conventions</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>All of the text of this specification is normative except sections
   explicitly marked as non-normative, examples, and notes. <a
   href="#ref-RFC2119">[RFC2119]<!--{{!RFC2119}}--></a>

  <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:

  <div class=example>
   <p>This is an example of an informative example.
  </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 class=note>Note, this is an informative note.

  <h3 id=conformance-classes><span class=secno>3.2. </span> Conformance
   classes</h3>

  <p>Conformance to CSS TEMPLATE Module Level N is defined for three
   conformance classes:

  <dl>
   <dt><dfn id=style-sheet title="style sheet!!as conformance class">style
    sheet</dfn>

   <dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#style-sheet">CSS
    style sheet</a>.

   <dt><dfn id=renderer>renderer</dfn>

   <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><dfn id=authoring-tool>authoring tool</dfn>

   <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 CSS TEMPLATE Module Level N 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>A renderer is conformant to CSS TEMPLATE Module Level N if, in addition
   to interpreting the style sheet as defined by the appropriate
   specifications, it supports all the features defined by CSS TEMPLATE
   Module Level N 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>An authoring tool is conformant to CSS TEMPLATE Module Level N 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.

  <h3 id=partial><span class=secno>3.3. </span> Partial implementations</h3&
2851
gt;

  <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.

  <h3 id=experimental><span class=secno>3.4. </span> Experimental
   implementations</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>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.

  <h3 id=testing><span class=secno>3.5. </span> Non-experimental
   implementations</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>To establish and maintain the interoperability of CSS across
   implementations, the CSS Working Group requests that non-experimental CSS
   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>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.

  <h3 id=cr-exit-criteria><span class=secno>3.6. </span> CR exit criteria</h3>

  <p class=replaceme>Remove this section unless/until the module is in CR.</p>
  <!-- This text was <a href="http://www.w3.org/Style/CSS/Tracker/actions/44"> decided on 2008-06-04.</a> -->

  <p> For this specification to be advanced to Proposed Recommendation, there
   must be at least two independent, interoperable implementations of each
   feature. Each feature may be implemented by a different set of products,
   there is no requirement that all features be implemented by a single
   product. For the purposes of this criterion, we define the following
   terms:

  <dl>
   <dt>independent

   <dd>each implementation must be developed by a different party and cannot
    share, reuse, or derive from code used by another qualifying
    implementation. Sections of code that have no bearing on the
    implementation of this specification are exempt from this requirement.

   <dt>interoperable

   <dd>passing the respective test case(s) in the official CSS test suite,
    or, if the implementation is not a Web browser, an equivalent test. Every
    relevant test in the test suite should have an equivalent test created if
    such a user agent (UA) is to be used to claim interoperability. In
    addition if such a UA is to be used to claim interoperability, then there
    must one or more additional UAs which can also pass those equivalent
    tests in the same way for the purpose of interoperability. The equivalent
    tests must be made publicly available for the purposes of peer review.

   <dt>implementation

   <dd>a user agent which:
    <ol class=inline>
     <li>implements the specification.

     <li>is available to the general public. The implementation may be a
      shipping product or other publicly available version (i.e., beta
      version, preview release, or “nightly build”). Non-shipping product
      releases must have implemented the feature(s) for a period of at least
      one month in order to demonstrate stability.

     <li>is not experimental (i.e., a version specifically designed to pass
      the test suite and is not intended for normal usage going forward).
    </ol>
  </dl>

  <p>The specification will remain Candidate Recommendation for at least six
   months.

  <h2 class=no-num id=acknowledgments> Acknowledgments</h2>

  <p><var class=replaceme>[acknowledgments]</var>

  <h2 class=no-num id=references> References</h2>

  <h3 class=no-num id=normative-references> Normative references</h3>
  <!--begin-normative-->
  <!-- Sorted by label -->

  <dl class=bibliography><!---->

   <dt id=CSS21>[CSS21]

   <dd>Bert Bos; et al. <a
    href="http://www.w3.org/TR/2011/REC-CSS2-20110607"><cite>Cascading Style
    Sheets Level 2 Revision 1 (CSS 2.1) Specification.</cite></a> 7 June
    2011. W3C Recommendation. URL: <a
    href="http://www.w3.org/TR/2011/REC-CSS2-20110607">http://www.w3.org/TR/2011/REC-CSS2-20110607</a>
   </dd>
   <!---->

   <dt id=CSS3SYN>[CSS3SYN]

   <dd>Tab Atkins Jr.; Simon Sapin. <a
    href="http://www.w3.org/TR/2014/CR-css-syntax-3-20140220/"><cite>CSS
    Syntax Module Level 3.</cite></a> 20 February 2014. W3C Candidate
    Recommendation. (Work in progress.) URL: <a
    href="http://www.w3.org/TR/2014/CR-css-syntax-3-20140220/">http://www.w3.org/TR/2014/CR-css-syntax-3-20140220/</a>
   </dd>
   <!---->

   <dt id=RFC2119>[RFC2119]

   <dd>S. Bradner. <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>Key
    words for use in RFCs to Indicate Requirement Levels.</cite></a> Internet
    RFC 2119. URL: <a
    href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>
   </dd>
   <!---->
  </dl>
  <!--end-normative-->

  <h3 class=no-num id=other-references> Other references</h3>
  <!--begin-informative-->
  <!-- Sorted by label -->

  <dl class=bibliography><!---->

   <dt id=CSS3VAL>[CSS3VAL]

   <dd>Håkon Wium Lie; Tab Atkins; Elika J. Etemad. <a
    href="http://www.w3.org/TR/2013/CR-css3-values-20130730/"><cite>CSS
    Values and Units Module Level 3.</cite></a> 30 July 2013. W3C Candidate
    Recommendation. (Work in progress.) URL: <a
    href="http://www.w3.org/TR/2013/CR-css3-values-20130730/">http://www.w3.org/TR/2013/CR-css3-values-20130730/</a>
   </dd>
   <!---->

   <dt id=HTML40>[HTML40]

   <dd>Ian Jacobs; David Raggett; Arnaud Le Hors. <a
    href="http://www.w3.org/TR/1998/REC-html40-19980424"><cite>HTML 4.0
    Specification.</cite></a> 24 April 1998. W3C Recommendation. URL: <a
    href="http://www.w3.org/TR/1998/REC-html40-19980424">http://www.w3.org/TR/1998/REC-html40-19980424</a>
   </dd>
   <!---->
  </dl>
  <!--end-informative-->

  <h2 class=no-num id=index> Index</h2>
  <!--begin-index-->

  <ul class=indexlist>
   <li>authoring tool, <a href="#authoring-tool"
    title="section 3.2."><strong>3.2.</strong></a>

   <li>Cross-references, <a href="#cross-references"
    title="section 2.1."><strong>2.1.</strong></a>

   <li>display-inside, <a href="#display-inside"
    title="section 2.1."><strong>2.1.</strong></a>

   <li>frequency
    <ul>
     <li>common, <a href="#common" title="section 2.">2.</a>
    </ul>

   <li>index, <a href="#index0" title="section 2."><strong>2.</strong></a>

   <li>renderer, <a href="#renderer"
    title="section 3.2."><strong>3.2.</strong></a>

   <li>resource
    <ul>
     <li>time spent, <a href="#work" title="section 2.">2.</a>
    </ul>

   <li>simple, <a href="#simplest" title="section 2.">2.</a>

   <li>simpler, <a href="#simplest" title="section 2.">2.</a>

   <li>simplest, <a href="#simplest" title="section 2.">2.</a>

   <li>style sheet
    <ul>
     <li>as conformance class, <a href="#style-sheet"
      title="section 3.2."><strong>3.2.</strong></a>
    </ul>

   <li>terms, <a href="#terms" title="section 2.">2.</a>

   <li>‘<code class=css>value-name</code>’, <a href="#value-name"
    title="section 2.1."><strong>2.1.</strong></a>

   <li>variant, <a href="#variants" title="section 2.">2.</a>

   <li>work, <a href="#work" title="section 2.">2.</a>
  </ul>
  <!--end-index-->

  <h2 class=no-num id=property-index> Property index</h2>
  <!--begin-properties-->

  <table class=proptable>
   <thead>
    <tr>
     <th>Property

     <th>Values

     <th>Initial

     <th>Applies to

     <th>Inh.

     <th>Percentages

     <th>Media

   <tbody>
    <tr>
     <th><a class=property href="#display-inside">display-inside</a>

     <td>inline-inside | block-inside | table | ruby | icon

     <td>text

     <td>all elements

     <td>no

     <td>N/A

     <td>visual
  </table>
  <!--end-properties-->
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