csswg-drafts/css-text-4/Overview.html at bd5b6a6b872f7a18d56886c76dd60d28c30fb185 · w3c/csswg-drafts · GitHub

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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"
"http://www.w3.org/TR/html4/strict.dtd">

<html lang=en>
 <head profile="http://dublincore.org/documents/2008/08/04/dc-html/ ">
  <meta content="text/html; charset=utf-8" http-equiv=Content-Type>
  <title>CSS Text Level 4</title>

  <link href="http://purl.org/dc/terms/" rel=schema.dcterms>
  <link href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
   rel=dcterms.rights>
  <meta content="CSS Text Level 4" name=dcterms.title>
  <meta content=text name=dcterms.type>
  <meta content=2014-02-03 name=dcterms.date>
  <meta content="Elika J. Etemad" name=dcterms.creator>
  <meta content="Koji Ishii" name=dcterms.creator>
  <meta content=W3C name=dcterms.publisher>
  <meta content="http://dev.w3.org/csswg/css3-text/" name=dcterms.identifier>
  <link href="../default.css" rel=stylesheet type="text/css">
  <style type="text/css">
    .egbidiwsaA,.egbidiwsbB,.egbidiwsaB,.egbidiwsbC
      { white-space:pre;font-size:80%;font-family:monospace; vertical-align:2px; margin:1px }
    .egbidiwsaA { background:lime;padding:2px; }
    .egbidiwsbB { border:2px solid blue }
    .egbidiwsaB { background:yellow;border:2px dotted white }
    .egbidiwsbC { border:2px dotted red }

    .char { border: 1px dotted gray; }
    .quarter { font-size: 25%; }
    tt[lang="ja"] { font-family: "MS Gothic", "Osaka", monospace }
  </style>
  <link href="http://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
   type="text/css">

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

   <h1>CSS Text Level 4</h1>

   <h2 class="no-num no-toc">Editor's Draft 3 February 2014</h2>

   <dl>
    <dt>This version:

    <dd><a href="http://dev.w3.org/csswg/css3-text/">$Date$ (CVS
     $Revision$)</a> <!--
      <dd><a href="http://www.w3.org/TR/2014/WD-css3-text-20140203/">http://www.w3.org/TR/2014/WD-css3-text-20140203/</a></dd>
    -->

    <dt>Latest version:

    <dd><a
     href="http://www.w3.org/TR/css3-text">http://www.w3.org/TR/css3-text</a>

    <dt>Latest editor's draft:

    <dd><a
     href="http://dev.w3.org/csswg/css3-text/">http://dev.w3.org/csswg/css3-text/</a>

    <dt>Previous version:

    <dd><a
     href="http://www.w3.org/TR/2011/WD-css3-text-20110901/">http://www.w3.org/TR/2011/WD-css3-text-20110901/</a>
    <dt>Feedback:

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

    <dt>Editors:

    <dd><a href="http://fantasai.inkedblade.net/contact">Elika J. Etemad</a>
     (Mozilla)

    <dd><a href="mailto:kojiishi@gluesoft.co.jp">Koji Ishii</a> (Invited
     Expert)
   </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>
  <details class=annoying-warning open=open> <summary>Not Ready For
  Implementation</summary>
  <p> This spec is not yet ready for implementation. It exists in this
   repository to record the ideas and promote discussion.

  <p> Before attempting to implement this spec, please contact the CSSWG at
   www-style@w3.org.
  </details>
  <h2 class="no-num no-toc" id=abstract>Abstract</h2>

  <p>This CSS3 module defines properties for text manipulation and specifies
   their processing model. It covers line breaking, justification and
   alignment, white space handling, text decoration and text transformation.

  <h2 class="no-num no-toc" id=status>Status of This Document</h2>

  <p><em>This section describes the status of this document at the time of
   its publication. Other documents may supersede this document. A list of
   current W3C publications and the latest revision of this technical report
   can be found in the <a href="http://www.w3.org/TR/">W3C technical reports
   index at http://www.w3.org/TR/.</a></em>

  <p>Publication as a Working Draft does not imply endorsement by the W3C
   Membership. This is a draft document and may be updated, replaced or
   obsoleted by other documents at any time. It is inappropriate to cite this
   document as other than work in progress.

  <p>This CSS module has been produced as a combined effort of the <a
   href="http://www.w3.org/International/Activity">W3C Internationalization
   Activity</a>, and the <a href="http://www.w3.org/Style/Activity">Style
   Activity</a> and is maintained by the <a
   href="http://www.w3.org/Style/CSS/members">CSS Working Group</a>. It also
   includes contributions made by participants in the <a
   href="http://www.w3.org/Style/XSL/Group/">XSL Working Group</a> (<a
   href="http://cgi.w3.org/MemberAccess/AccessRequest">members only</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><strong>Feedback on this draft should be posted to the (<a
   href="http://lists.w3.org/Archives/Public/www-style/">archived</a>) public
   mailing list <a
   href="mailto:www-style@w3.org">www-style@w3.org</a></strong> (see <a
   href="http://www.w3.org/Mail/Request">instructions</a>) <strong>with
   <kbd>[css3-text]</kbd> in the subject line.</strong> You are strongly
   encouraged to complain if you see something stupid in this draft. The
   editors will do their best to respond to all feedback.

  <p><strong>If you have implemented properties from the <a
   href="http://www.w3.org/TR/2003/CR-css3-text-20030514/">May 2003 CSS3 Text
   CR</a></strong> <em>please</em> let us know so we can take that into
   account as we redraft the spec. You can post to <a
   href="http://lists.w3.org/Archives/Public/www-style/">www-style</a>
   (public), post to the <a
   href="http://lists.w3.org/Archives/Member/w3c-css-wg/">CSS WG mailing
   list</a> (<a
   href="http://cgi.w3.org/MemberAccess/AccessRequest">Member-restricted</a>),
   or <a href="http://fantasai.inkedblade.net/contact">email fantasai
   directly</a> (personal).

  <p>The following features are at risk and may be cut from the spec during
   its CR period if there are no (correct) implementations:

  <ul>
   <li>the &lt;length> values of the ‘<a href="#tab-size0"><code
    class=property>tab-size</code></a>’ property

   <li>the ‘<a href="#hanging-punctuation0"><code
    class=property>hanging-punctuation</code></a>’ property

   <li>the percentage values of ‘<a href="#letter-spacing0"><code
    class=property>letter-spacing</code></a>’ and ‘<a
    href="#word-spacing0"><code class=property>word-spacing</code></a>’

   <li>the ‘<code class=css>hyphenate-limit-*</code>’ properties

   <li>the ‘<a href="#text-spacing"><code
    class=property>text-spacing</code></a>’ property

   <li>the ‘<a href="#text-decoration-skip0"><code
    class=property>text-decoration-skip</code></a>’ property / ‘<code
    class=css>ink</code>’ value

   <li>the ‘<a href="#text-emphasis-skip0"><code
    class=property>text-emphasis-skip</code></a>’ property

   <li><span class=issue>audit draft and add more here</span>
  </ul>

  <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>

     <li><a href="#terms"><span class=secno>1.3. </span> Terminology</a>
    </ul>

   <li><a href="#transforming"><span class=secno>2. </span> Transforming
    Text</a>
    <ul class=toc>
     <li><a href="#text-transform"><span class=secno>2.1. </span>
      Transforming Text: the ‘<code class=property>text-transform</code>’
      property</a>
    </ul>

   <li><a href="#white-space-processing"><span class=secno>3. </span> White
    Space Processing</a>
    <ul class=toc>
     <li><a href="#white-space-collapsing"><span class=secno>3.1. </span>
      White Space Collapsing: the ‘<code
      class=property>text-space-collapse</code>’ property</a>

     <li><a href="#tab-size"><span class=secno>3.2. </span> Tab Character
      Size: the ‘<code class=property>tab-size</code>’ property</a>

     <li><a href="#white-space-rules"><span class=secno>3.3. </span> The
      White Space Processing Rules</a>
      <ul class=toc>
       <li><a href="#egbidiwscollapse"><span class=secno>3.3.1. </span>
        Example of bidirectionality with white space collapsing</a>

       <li><a href="#line-break-transform"><span class=secno>3.3.2. </span>
        Line Feed Transformation Rules</a>

       <li><a href="#white-space-summary"><span class=secno>3.3.3. </span>
        Informative Summary of White Space Collapsing Effects</a>
      </ul>

     <li><a href="#white-space"><span class=secno>3.4. </span> White Space
      and Text Wrapping Shorthand: the ‘<code
      class=property>white-space</code>’ property</a>
    </ul>

   <li><a href="#line-breaking"><span class=secno>4. </span> Line Breaking
    and Word Boundaries</a>
    <ul class=toc>
     <li><a href="#line-break"><span class=secno>4.1. </span> Line Breaking
      Strictness: the ‘<code class=property>line-break</code>’
      property</a>

     <li><a href="#word-break"><span class=secno>4.2. </span> Word Breaking
      Rules: the ‘<code class=property>word-break</code>’ property</a>
    </ul>

   <li><a href="#hyphenation"><span class=secno>5. </span>Hyphenation</a>
    <ul class=toc>
     <li><a href="#hyphens"><span class=secno>5.1. </span>Hyphenation
      Control: the ‘<code class=property>hyphens</code>’ property</a>

     <li><a href="#hyphenate-character"><span class=secno>5.2. </span>
      Hyphens: the ‘<code class=property>hyphenate-character</code>’
      property</a>

     <li><a href="#hyphenate-size-limits"><span class=secno>5.3. </span>
      Hyphenation Size Limit: the ‘<code
      class=property>hyphenate-limit-zone</code>’ property</a>

     <li><a href="#hyphenate-char-limits"><span class=secno>5.4. </span>
      Hyphenation Character Limits: the ‘<code
      class=property>hyphenate-limit-chars</code>’ property</a>

     <li><a href="#hyphenate-line-limits"><span class=secno>5.5. </span>
      Hyphenation Line Limits: the ‘<code
      class=property>hyphenate-limit-lines</code>’ and ‘<code
      class=property>hyphenate-limit-last</code>’ properties</a>
    </ul>

   <li><a href="#wrapping"><span class=secno>6. </span> Text Wrapping</a>
    <ul class=toc>
     <li><a href="#text-wrap"><span class=secno>6.1. </span> Text Wrap
      Settings: the ‘<code class=property>text-wrap</code>’ property</a>
      <ul class=toc>
       <li><a href="#example-avoid"><span class=secno>6.1.1. </span> Example
        of using ‘<code class=css>text-wrap: avoid</code>’ in presenting
        a footer</a>
      </ul>

     <li><a href="#overflow-wrap"><span class=secno>6.2. </span> Emergency
      Wrapping: the ‘<code class=property>overflow-wrap</code>’
      property</a>
    </ul>

   <li><a href="#justification"><span class=secno>7. </span> Alignment and
    Justification</a>
    <ul class=toc>
     <li><a href="#text-align"><span class=secno>7.1. </span> Text Alignment:
      the ‘<code class=property>text-align</code>’ property</a>
      <ul class=toc>
       <li><a href="#character-alignment"><span class=secno>7.1.1.
        </span>Character-based Alignment in a Table Column</a>
      </ul>

     <li><a href="#text-align-last"><span class=secno>7.2. </span> Last Line
      Alignment: the ‘<code class=property>text-align-last</code>’
      property</a>

     <li><a href="#text-justify"><span class=secno>7.3. </span> Justification
      Method: the ‘<code class=property>text-justify</code>’ property</a>
    </ul>

   <li><a href="#spacing"><span class=secno>8. </span> Spacing</a>
    <ul class=toc>
     <li><a href="#word-spacing"><span class=secno>8.1. </span> Word Spacing:
      the ‘<code class=property>word-spacing</code>’ property</a>

     <li><a href="#letter-spacing"><span class=secno>8.2. </span> Tracking:
      the ‘<code class=property>letter-spacing</code>’ property</a>

     <li><a href="#text-spacing-prop"><span class=secno>8.3. </span>
      Character Class Spacing: the ‘<code
      class=property>text-spacing</code>’ property</a>
      <ul class=toc>
       <li><a href="#fullwidth-collapsing"><span class=secno>8.3.1. </span>
        Fullwidth Punctuation Collapsing</a>

       <li><a href="#text-spacing-classes"><span class=secno>8.3.2. </span>
        Text Spacing Character Classes</a>
      </ul>
    </ul>

   <li><a href="#edge-effects"><span class=secno>9. </span> Edge Effects</a>
    <ul class=toc>
     <li><a href="#text-indent"><span class=secno>9.1. </span> First Line
      Indentation: the ‘<code class=property>text-indent</code>’
      property</a>

     <li><a href="#hanging-punctuation"><span class=secno>9.2. </span>
      Hanging Punctuation: the ‘<code
      class=property>hanging-punctuation</code>’ property</a>
    </ul>

   <li><a href="#decoration"><span class=secno>10. </span>Text Decoration</a>

    <ul class=toc>
     <li><a href="#line-decoration"><span class=secno>10.1. </span> Line
      Decoration: Underline, Overline, and Strike-Through</a>
      <ul class=toc>
       <li><a href="#text-decoration-line"><span class=secno>10.1.1. </span>
        Text Decoration Lines: the ‘<code
        class=property>text-decoration-line</code>’ property</a>

       <li><a href="#text-decoration-color"><span class=secno>10.1.2. </span>
        Text Decoration Color: the ‘<code
        class=property>text-decoration-color</code>’ property</a>

       <li><a href="#text-decoration-style"><span class=secno>10.1.3. </span>
        Text Decoration Style: the ‘<code
        class=property>text-decoration-style</code>’ property</a>

       <li><a href="#text-decoration"><span class=secno>10.1.4. </span> Text
        Decoration Shorthand: the ‘<code
        class=property>text-decoration</code>’ property</a>

       <li><a href="#text-decoration-skip"><span class=secno>10.1.5. </span>
        Text Decoration Line Continuity: the ‘<code
        class=property>text-decoration-skip</code>’ property</a>

       <li><a href="#text-underline-position"><span class=secno>10.1.6.
        </span> Text Underline Position: the ‘<code
        class=property>text-underline-position</code>’ property</a>
      </ul>

     <li><a href="#emphasis-marks"><span class=secno>10.2. </span> Emphasis
      Marks</a>
      <ul class=toc>
       <li><a href="#text-emphasis-style"><span class=secno>10.2.1. </span>
        Emphasis Mark Style: the ‘<code
        class=property>text-emphasis-style</code>’ property</a>

       <li><a href="#text-emphasis-color"><span class=secno>10.2.2. </span>
        Emphasis Mark Color: the ‘<code
        class=property>text-emphasis-color</code>’ property</a>

       <li><a href="#text-emphasis"><span class=secno>10.2.3. </span>
        Emphasis Mark Shorthand: the ‘<code
        class=property>text-emphasis</code>’ property</a>

       <li><a href="#text-emphasis-position"><span class=secno>10.2.4.
        </span> Emphasis Mark Position: the ‘<code
        class=property>text-emphasis-position</code>’ property</a>

       <li><a href="#text-emphasis-skip"><span class=secno>10.2.5. </span>
        Emphasis Mark Skip: the ‘<code
        class=property>text-emphasis-skip</code>’ property</a>
      </ul>

     <li><a href="#text-shadow"><span class=secno>10.3. </span> Text Shadows:
      the ‘<code class=property>text-shadow</code>’ property</a>
    </ul>

   <li><a href="#conformance"><span class=secno>11. </span> Conformance</a>
    <ul class=toc>
     <li><a href="#conventions"><span class=secno>11.1. </span> Document
      Conventions</a>

     <li><a href="#conformance-classes"><span class=secno>11.2. </span>
      Conformance Classes</a>

     <li><a href="#partial"><span class=secno>11.3. </span> Partial
      Implementations</a>

     <li><a href="#experimental"><span class=secno>11.4. </span> Experimental
      Implementations</a>

     <li><a href="#testing"><span class=secno>11.5. </span>Non-Experimental
      Implementations</a>

     <li><a href="#cr-exit-criteria"><span class=secno>11.6. </span> CR Exit
      Criteria</a>
    </ul>

   <li class=no-num><a href="#acknowledgements"> Appendix A:
    Acknowledgements</a>

   <li class=no-num><a href="#appendix-b-references">Appendix B:
    References</a>
    <ul class=toc>
     <li class=no-num><a href="#normative-ref">Normative references</a>

     <li class=no-num><a href="#informative-ref">Informative references</a>
    </ul>

   <li class=no-num><a href="#changes">Appendix C: Changes</a>

   <li class=no-num><a href="#default-stylesheet">Appendix D: Default UA
    Stylesheet</a>

   <li class=no-num><a href="#script-groups">Appendix E: Scripts and
    Spacing</a>

   <li class=no-num><a href="#small-kana">Appendix F: Small Kana Mappings</a>

   <li class=no-num><a
    href="#appendix-g-text-processing-order-of-oper">Appendix G: Text
    Processing Order of Operations</a>

   <li class=no-num><a href="#appendix-h-full-property-index">Appendix H:
    Full Property Index</a>

   <li class=no-num><a href="#traditions">Appendix J: Cultural
    Correlations</a>
  </ul>
  <!--end-toc-->

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

  <p>[document here]

  <p class=issue>This draft describes features that are specific to certain
   scripts. There is an ongoing discussion about where these features belong:
   in existing CSS properties, in new CSS properties, or perhaps in other
   specifications.

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

  <p>This module replaces and extends the text-level features defined in <a
   href="#ref-CSS21" rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a> chapter 16.

  <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"
   rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>. Value types not defined in
   this specification are defined in CSS Level 2 Revision 1 <a
   href="#ref-CSS21" rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>. Other CSS
   modules may expand the definitions of these value types: for example <a
   href="#ref-CSS3COLOR" rel=biblioentry>[CSS3COLOR]<!--{{CSS3COLOR}}--></a>,
   when combined with this module, expands the definition of the
   &lt;color&gt; 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.

  <h3 id=terms><span class=secno>1.3. </span> Terminology</h3>

  <p id=grapheme-cluster>A <dfn id=grapheme-cluster0>grapheme cluster</dfn>
   is what a language user considers to be a character or a basic unit of the
   script. The term is described in detail in the Unicode Technical Report:
   Text Boundaries <a href="#ref-UAX29"
   rel=biblioentry>[UAX29]<!--{{!UAX29}}--></a>. This specification uses the
   <em>extended grapheme cluster</em> definition in <a href="#ref-UAX29"
   rel=biblioentry>[UAX29]<!--{{!UAX29}}--></a> (not the <em>legacy grapheme
   cluster</em> definition). The UA may further tailor the definition as
   allowed by Unicode. Within this specification, the ambiguous term <dfn
   id=character>character</dfn> is used as a friendlier synonym for <a
   href="#grapheme-cluster0"><i>grapheme cluster</i></a>. See <a
   href="http://dev.w3.org/csswg/css3-writing-modes/#character-properties">Characters
   and Properties</a> for how to determine the Unicode properties of a
   character.

  <p id=letter>A <dfn id=letter0>letter</dfn> for the purpose of this
   specification is a <a href="#character"><i>character</i></a> belonging to
   one of the Letter or Number general categories in Unicode. <a
   href="#ref-UAX44" rel=biblioentry>[UAX44]<!--{{!UAX44}}--></a>

  <h2 id=transforming><span class=secno>2. </span> Transforming Text</h2>

  <h3 id=text-transform><span class=secno>2.1. </span> <a name=caps-prop></a>
   Transforming Text: the ‘<a href="#text-transform0"><code
   class=property>text-transform</code></a>’ property</h3>

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

     <td><dfn id=text-transform0>text-transform</dfn>

    <tr>
     <th>Value:

     <td>none | [ [ capitalize | uppercase | lowercase ] || full-width ||
      full-size-kana ]

    <tr>
     <th>Initial:

     <td>none

    <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
  </table>

  <p>This property transforms text for styling purposes. Values have the
   following meanings:

  <dl>
   <dt><dfn id=none title="text-transform:none">‘<code
    class=css>none</code>’</dfn>

   <dd>No effects.

   <dt><dfn id=capitalize title="text-transform:capitalize">‘<code
    class=css>capitalize</code>’</dfn>

   <dd>Puts the first <a href="#letter0"><i>letter</i></a> of each word in
    titlecase; other characters are unaffected.

   <dt><dfn id=uppercase title="text-transform:uppercase">‘<code
    class=css>uppercase</code>’</dfn>

   <dd>Puts all characters in uppercase.

   <dt><dfn id=lowercase title="text-transform:lowercase">‘<code
    class=css>lowercase</code>’</dfn>

   <dd>Puts all characters in lowercase.

   <dt><dfn id=full-width title="text-transform:full-width">‘<code
    class=css>full-width</code>’</dfn>

   <dd>Puts all characters in fullwidth form. If the character does not have
    a corresponding fullwidth form, it is left as is. This value is typically
    used to typeset Latin characters and digits like ideographic characters.

   <dt><dfn id=full-size-kana title="text-transform:full-size-kana">‘<code
    class=css>full-size-kana</code>’</dfn>

   <dd>Converts all small Kana characters to normal Kana. This value is
    typically used for ruby annotation text, where all small Kana should be
    drawn as large Kana.
  </dl>

  <p>The case mapping rules for the character repertoire specified by the
   Unicode Standard can be found on the Unicode Consortium Web site <a
   href="#ref-UNICODE" rel=biblioentry>[UNICODE]<!--{{!UNICODE}}--></a>. The
   UA must use the full case mappings for Unicode characters, including any
   conditional casing rules, as defined in Default Case Algorithm section. If
   (and only if) the content language of the element is, according to the
   rules of the document language, known, then any appropriate
   language-specific rules must be applied as well. These minimally include,
   but are not limited to, the language-specific rules in Unicode's <a
   href="http://www.unicode.org/Public/UNIDATA/SpecialCasing.txt">SpecialCasing.txt</a>.

  <div class=example>
   <p>For example, in Turkish there are two “i”s, one with a
    dot—“İ” and “i”— and one without—“I” and “ı”.
    Thus the usual case mappings between “I” and “i” are replaced
    with a different set of mappings to their respective undotted/dotted
    counterparts, which do not exist in English. This mapping must only take
    effect if the language is known to be Turkish or Azeri; in other
    languages, the usual mapping of “I” and “i” is required. This
    rule is thus conditionally defined in Unicode's SpecialCasing.txt file.
  </div>
  <!--
    <div class="example">
      <p>An example where the UA may choose to include rules beyond those
        in Unicode is Greek. In Greek, if the entire word is in upper case,
        accents are dropped or transformed
       http://blogs.msdn.com/b/michkap/archive/2006/08/18/706383.aspx
    </div>
-->

  <p>The definition of "word" used for ‘<code
   class=css>capitalize</code>’ is UA-dependent; <a href="#ref-UAX29"
   rel=biblioentry>[UAX29]<!--{{!UAX29}}--></a> is suggested (but not
   required) for determining such word boundaries. Authors should not expect
   ‘<code class=css>capitalize</code>’ to follow language-specific
   titlecasing conventions (such as skipping articles in English).

  <p>The definition of fullwidth and halfwidth forms can be found on the
   Unicode consortium web site at <a href="#ref-UAX11"
   rel=biblioentry>[UAX11]<!--{{!UAX11}}--></a>. The mapping to fullwidth
   form is defined by taking code points with the &lt;wide&gt; or the
   &lt;narrow&gt; tag in their Decomposition_Mapping in <a href="#ref-UAX44"
   rel=biblioentry>[UAX44]<!--{{!UAX44}}--></a>. For the &lt;narrow&gt; tag,
   the mapping is from the code point to the decomposition (minus
   &lt;narrow&gt; tag), and for the &lt;wide&gt; tag, the mapping is from the
   decomposition (minus the &lt;wide&gt; tag) back to the original code
   point.

  <p>The mappings for small Kana to normal Kana are defined in <a
   href="#small-kana">Small Kana Mappings</a>.

  <p>When multiple values are specified and therefore multiple
   transformations need to be applied, they are applied in the following
   order:

  <ol>
   <li>‘<code class=css>capitalize</code>’, ‘<code
    class=css>uppercase</code>’, and ‘<code class=css>lowercase</code>’

   <li>‘<code class=css>full-width</code>’

   <li>‘<code class=css>full-size-kana</code>’
  </ol>

  <p>Text transformation happens after <a href="#white-space-rules">white
   space processing</a>, which means that ‘<code
   class=css>full-width</code>’ transforms only preserved U+0020 spaces to
   U+3000.

  <div class=example>
   <p>The following example converts the ASCII characters in abbreviations in
    Japanese to their fullwidth variants so that they lay out and line break
    like ideographs:

   <pre>abbr:lang(ja) { text-transform: full-width; }</pre>
  </div>

  <p class=issue>All-caps text sometimes has special typographic
   considerations. For example: Punctuation and number glyphs might be
   adjusted for the higher "center of gravity" (see the <a
   href="http://www.microsoft.com/typography/otspec/features_ae.htm#case">case</a>
   feature in OpenType). Should we turn that on by default, as they suggest?

  <p class=issue>CSS may introduce the ability to create custom mapping
   tables for less common text transforms, such as by an ‘<code
   class=css>@text-transform</code>’ rule similar to ‘<code
   class=css>@counter-style</code>’ from <a href="#ref-CSS3LIST"
   rel=biblioentry>[CSS3LIST]<!--{{CSS3LIST}}--></a>, and this mechanism may
   be used to replace ‘<code class=css>full-size-kana</code>’.

  <h2 id=white-space-processing><span class=secno>3. </span> White Space
   Processing</h2>

  <p>The source text of a document often contains formatting that is not
   relevant to the final rendering: for example, breaking the source into
   segments (lines) for ease of editing or adding white space characters such
   as tabs and spaces to indent the source code. CSS white space processing
   allows the author to control interpretation of such formatting: to
   preserve or collapse it away when rendering the document.

  <p id=segment-normalization> In the document source, segments can be
   delimited by carriage returns (U+000D), linefeeds (U+000A) or a
   combination (U+000D U+000A), or by some other mechanism, such as the SGML
   RECORD-START and RECORD-END tokens. If no segmentation rules are specified
   for the document language, each line feed (U+000A), carriage return
   (U+000D) and CRLF sequence (U+000D U+000A) in the text is considered a
   segment break. (This default rule also applies to generated content.) In
   CSS, each such segment break is treated as a single line feed character
   (U+000A).

  <p>White space processing in CSS interprets white space characters only for
   rendering: it has no effect on the underlying document data.

  <p class=note>Note that the document parser may have not only normalized
   segment breaks, but also collapsed other space characters or otherwise
   processed white space according to markup rules. Because CSS processing
   occurs <em>after</em> the parsing stage, it is not possible to restore
   these characters for styling. Therefore, some of the behavior specified
   below can be affected by these limitations and may be user agent
   dependent.

  <p>Control characters (Unicode class Cc) other than tab (U+0009), line feed
   (U+000A), space (U+0020), and the bidi formatting characters
   (U+202<var>x</var>) should be rendered as invisible zero-width characters.
   UAs may instead treat them as visible characters. (Note, however, that
   this will usually result in them being rendered as missing glyphs.) <span
   class=issue>What's the line-breaking behavior? Effects on joining? Can we
   just copy the behavior of some zero-width Unicode character?</span>

  <h3 id=white-space-collapsing><span class=secno>3.1. </span> White Space
   Collapsing: the ‘<a href="#text-space-collapse"><code
   class=property>text-space-collapse</code></a>’ property</h3>

  <p class=issue>This section is still under discussion and may change in
   future drafts.

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

     <td><dfn id=text-space-collapse>text-space-collapse</dfn>

    <tr>
     <th>Value:

     <td>collapse | discard | [ [preserve | preserve-breaks] && [ trim-inner
      || consume-before || consume-after ]

    <tr>
     <th>Initial:

     <td>collapse

    <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>specified value
  </table>

  <p class=issue>Need a property name

  <p>This property declares whether and how <a
   href="#white-space-processing">white space</a> inside the element is
   collapsed. Values have the following meanings, which must be interpreted
   according to the <a href="#white-space-rules">white space processing
   rules</a>:

  <dl>
   <dt><dfn id=collapse0 title="white-space:collapse">‘<code
    class=css>collapse</code>’</dfn>

   <dd>This value directs user agents to collapse sequences of white space
    into a single character (or <a href="#line-break-transform">in some
    cases</a>, no character).

   <dt><dfn id=preserve title="white-space:preserve">‘<code
    class=css>preserve</code>’</dfn>

   <dd>This value prevents user agents from collapsing sequences of white
    space. Line feeds are preserved as forced line breaks.

   <dt><dfn id=preserve-breaks title="white-space:preserve-breaks">‘<code
    class=css>preserve-breaks</code>’</dfn>

   <dd>This value collapses white space as for ‘<code
    class=css>collapse</code>’, but preserves line feeds as forced line
    breaks.

   <dt><dfn id=discard title="white-space:discard">‘<code
    class=css>discard</code>’</dfn>

   <dd>This value directs user agents to "discard" all white space in the
    element.

   <dt><dfn id=trim-inner title="white-space:trim-inner">‘<code
    class=css>trim-inner</code>’</dfn>

   <dd>For block containers this value directs UAs to discard all whitespace
    at the beginning of the element up to and including the last line feed
    before the first non-white-space character in the element as well as to
    discard all white space at the end of the element starting with the first
    line feed after the last non-white-space character in the element. For
    other elements this value directs UAs to discard all whitespace at the
    beginning and end of the element.

   <dt><dfn id=consume-before title="white-space:consume-before">‘<code
    class=css>consume-before</code>’</dfn>

   <dd>This value directs the UA to collapse all collapsible whitespace
    immediately before the start of the element.

   <dt><dfn id=consume-after title="white-space:consume-after">‘<code
    class=css>consume-after</code>’</dfn>

   <dd>This value directs the UA to collapse all collapsible whitespace
    immediately after the end of the element.
  </dl>

  <div class=example>
   <p>The following style rules implement MathML's white space processing:

   <pre>
<!-- -->@namespace m "http://www.w3.org/1998/Math/MathML";
<!-- -->m|* {
<!-- -->  text-space-collapse: discard;
<!-- -->}
<!-- -->m|mi, m|mn, m|mo, m|ms, m|mtext {
<!-- -->  text-space-collapse: trim-inner;
<!-- -->}</pre>
  </div>

  <div class=example>
   <p>The following style rules render DT elements as a comma-separated list:

   <pre>
<!-- -->dt { display: inline; }
<!-- -->dt + dt:before { content: ", "; text-space-collapse: consume-before; }</pre>
  </div>

  <p class=issue>It's been pointed out that ‘<code
   class=css>trim-inner</code>’, ‘<code
   class=css>consume-before</code>’, and ‘<code
   class=css>consume-after</code>’ won't work well because ‘<a
   href="#text-space-collapse"><code
   class=property>text-space-collapse</code></a>’ is inherited, meaning
   that inserting a &lt;span> or &gt;div> would cause more white space to be
   removed than otherwise.

  <h3 id=tab-size><span class=secno>3.2. </span> Tab Character Size: the
   ‘<a href="#tab-size0"><code class=property>tab-size</code></a>’
   property</h3>

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

     <td><dfn id=tab-size0>tab-size</dfn>

    <tr>
     <th>Value:

     <td>&lt;integer&gt; | &lt;length&gt;

    <tr>
     <th>Initial:

     <td>8

    <tr>
     <th>Applies to:

     <td>block containers

    <tr>
     <th>Inherited:

     <td>yes

    <tr>
     <th>Percentages:

     <td>N/A

    <tr>
     <th>Media:

     <td>visual

    <tr>
     <th>Computed value:

     <td>specified value
  </table>

  <p>This property determines the measure of the tab character (U+0009) when
   rendered. Integers represent the measure in space characters (U+0020).
   Negative integers are not allowed.

  <h3 id=white-space-rules><span class=secno>3.3. </span> The White Space
   Processing Rules</h3>

  <p>White space processing affects only spaces (U+0020), tabs (U+0009), and
   (<a href="#segment-normalization">post-normalization</a>) line feeds
   (U+00A0).

  <p>For each inline (including anonymous inlines) within an inline
   formatting context, white space characters are handled as follows,
   ignoring bidi formatting characters as if they were not there:

  <ul>
   <li id=collapse>
    <p>If ‘<a href="#text-space-collapse"><code
     class=property>text-space-collapse</code></a>’ is set to ‘<code
     class=css>collapse</code>’ or ‘<code
     class=css>preserve-breaks</code>’, white space characters are
     considered <dfn id=collapsible>collapsible</dfn> and are processed by
     performing the following steps:

    <ol>
     <li>All spaces and tabs immediately preceding or following a line feed
      character are removed.

     <li>If ‘<a href="#text-space-collapse"><code
      class=property>text-space-collapse</code></a>’ is not ‘<code
      class=css>preserve-breaks</code>’, line feed characters are
      transformed for rendering according to the <a
      href="#line-break-transform">line feed transformation rules</a>.

     <li>Every tab is converted to a space (U+0020).

     <li>Any space immediately following another collapsible space —even
      one outside the boundary of the inline—is removed. However, if
      removing this space would eliminate a line breaking opportunity in the
      text, that opportunity is still considered to exist.

     <li>A collapsible space immediately preceding an element with ‘<code
      class=css>consume-before</code>’ is removed. Such removed spaces do
      not indicate a line breaking opportunity in the text.

     <li>Any collapsible spaces after the end of an element with ‘<code
      class=css>consume-after</code>’ are removed. Such removed spaces do
      not indicate a line breaking opportunity in the text.
    </ol>

   <li>
    <p>If ‘<a href="#text-space-collapse"><code
     class=property>text-space-collapse</code></a>’ is set to ‘<code
     class=css>preserve</code>’, any sequence of spaces unbroken by an
     element boundary is treated as a sequence of non-breaking spaces.
     However, a line breaking opportunity exists at the end of the sequence.

   <li>
    <p>If ‘<a href="#text-space-collapse"><code
     class=property>text-space-collapse</code></a>’ is set to ‘<code
     class=css>discard</code>’, the first white space character in every
     white space sequence is converted to a zero width non-joiner (U+200C)
     and the rest of the sequence is removed.
  </ul>

  <p>Then, the entire block is rendered. Inlines are laid out, taking bidi
   reordering into account, and wrapping as specified by the ‘<a
   href="#text-wrap0"><code class=property>text-wrap</code></a>’ property.

  <p>As each line is laid out,

  <ol>
   <li>A sequence of collapsible spaces at the beginning of a line is
    removed.

   <li>Each tab is rendered as a horizontal shift that lines up the start