csswg-drafts/css-page-template/Overview.html at 7d6bab922cce3c47fc1bfe572383cb1f128fa1c1 · w3c/csswg-drafts · GitHub

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<!DOCTYPE html>

<html lang=en>
 <head profile="http://www.w3.org/2006/03/hcard">
  <meta content="text/html; charset=UTF-8" http-equiv=Content-Type>
  <title>CSS Pagination Templates Module Level 3</title>
  <!--
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  <meta content="CSS Pagination Templates Module Level 3" name=dcterms.title>
  <meta content=text name=dcterms.type>
  <meta content=2014-02-03 name=dcterms.date>
  <meta content="Alan Stearns" name=dcterms.creator>
  <meta content=W3C name=dcterms.publisher>
  <meta content="http://dev.w3.org/csswg/css3-page-template/"
   name=dcterms.identifier>
  <link href="../shared/style/default.css" rel=stylesheet type="text/css"><!--link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/W3C-ED.css"-->

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   rel=stylesheet type="text/css">
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    body {
        counter-reset: issue;
    }
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   title="alternate spec style" 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 Pagination Templates Module Level 3</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-page-template/">http://dev.w3.org/csswg/css3-page-template/</a>-->

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

    <dt>Latest version:
     <!--<dd><a href="http://www.w3.org/TR/css3-page-template/">http://www.w3.org/TR/css3-page-template/</a>-->

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

    <dt>Editor's draft:

    <dd><a
     href="//dev.w3.org/csswg/css3-page-template/">http://dev.w3.org/csswg/css3-page-template/</a>
     <!--
    <dt>Previous version:
    <dd><a href="http://www.w3.org/PreviousVersionURI">
      http://www.w3.org/PreviousVersionURI</a>
  -->

    <dt>Feedback:

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

    <dt>Editors:

    <dd class=vcard><span class=fn>Alan Stearns</span>, <span class=org>Adobe
     Systems, Inc.</span>, <span class=email>stearns@adobe.com</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>
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   <!--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>The Pagination Templates module describes templates that generate boxes
   in CSS to display content in a paginated view. These templates define a
   page containing one or more boxes with content assignments. As content
   overflows additional pages are generated using template selection rules
   until all of the content is displayed.

  <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=%5Bcss3-page-template%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
   “css3-page-template” in the subject, preferably like this:
   “[<!---->css3-page-template<!---->] <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: none

  <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>
    </ul>

   <li><a href="#templates-and-slots"><span class=secno>2. </span>Pagination
    Templates and Slots</a>

   <li><a href="#conditional-templates"><span class=secno>3. </span>Template
    Selection</a>
    <ul class=toc>
     <li><a href="#ordered-templates"><span class=secno>3.1. </span>Selecting
      Templates by Page Order</a>

     <li><a href="#selection-from-required-flows"><span class=secno>3.2.
      </span>Selecting Templates from Required Flows</a>

     <li><a href="#selection-from-available-content"><span class=secno>3.3.
      </span>Selecting Templates from Available Content</a>
    </ul>

   <li><a href="#cssom"><span class=secno>4. </span>CSS Object Model</a>

   <li><a href="#conformance"><span class=secno>5. </span>Conformance</a>

   <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>
  </ul>
  <!--end-toc-->

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

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

  <p>This module describes how to define pagination templates in CSS. In CSS
   2.1 content displayed on-screen is assumed to be a single continuous
   canvas. Pagination templates provide a mechanism for a ‘<code
   class=property>paginated</code>’ experience that applies to on-screen
   presentation as well as printed media. Pagination templates define boxes
   in CSS where content is displayed as the user moves from page to page on
   screen or prints the document. When content is laid out using pagination
   templates, pages are generated as needed to accommodate all the content.

  <div class="issue-marker wrapper">
   <div class=issue-marker>
    <div class=issue-details>The draft as it stands requires pagination to
     present the repeated template layouts. Other methods of repeating
     template layouts to accommodate content might be specified, but the
     draft would need to be reviewed to remove all reliances on paged
     displays.</div>
   </div>

   <div class=issue-marker>
    <div class=issue-details>The terms ‘<code
     class=property>template</code>’ and ‘<code
     class=property>page</code>’ are overloaded in CSS, but they are the
     words that most clearly describe the concept. Some alternates for the
     main @ rule: template, page-template, view-template, page-master,
     master-template, master. Other suggestions are welcome, but only if they
     are more helpful than onelook.com (which suggested "Captain Submarine").</div>
   </div>

   <div class=issue-marker>
    <div class=issue-details>This specification may be the best place to
     define "continued here" or "continued on page x" generated content,
     since this spec defines ways to skip pages (that basic pagination may
     not).</div>
   </div>
  </div>

  <p>Pagination templates consist of anonymous boxes called slots created by
   CSS to contain content. Layouts that use pagination templates mainly
   determine the size of these slots from the template definition instead of
   the size of their content. When content does not fit into a template slot,
   additional pages are created with more slots to contain the overflow
   content.

  <p>Multiple pagination templates can be defined for a given document. A
   paginated element can use a single template or select from a set of
   templates each time a new page needs to be generated. Which template is
   used for a given page can be defined by a selector or by choosing a
   template based on available content. Elements can further constrain the
   applicable template set by listing a subset of templates that apply.

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

  <p>This module uses named flows and region chains defined in <a
   href="#ref-CSS3-REGIONS">[CSS3-REGIONS]<!--{{CSS3-REGIONS}}--></a>.

  <p>This module uses the overflow-style property from <a
   href="#ref-CSS3GCPM">[CSS3GCPM]<!--{{CSS3GCPM}}--></a>.

  <p>Some examples use positioning from <a
   href="#ref-CSS3GRID">[CSS3GRID]<!--{{CSS3GRID}}--></a>.

  <h2 id=templates-and-slots><span class=secno>2. </span>Pagination Templates
   and Slots</h2>

  <p>An @template rule defines and names a pagination template. Pagination
   templates contain one or more slots to display content. These slots create
   boxes for each page generated from a pagination template. An element can
   use pagination templates if its ‘<code
   class=property>overflow-style</code>’ property is set to any of the
   paged-* values defined in css3-gcpm. If a document defines no pagination
   templates, then there is an implicit pagination template with a single
   slot containing the paginated element's contents.

  <div class=issue-marker>
   <div class=issue-details>Instead of a dependency on GCPM, this spec could
    define what happens with a paginated view, without specifying how the
    paginated view comes into existence. What happens when you apply ‘<code
    class=css>overflow-style:paged-x</code>’ to an iframe or region?</div>
  </div>

  <p>The box created from an @template rule defaults to the size of the
   paginated element's box.

  <p>A slot is an anonymous box in a pagination template where content can be
   placed. In an @template rule @slot rules create slots. The order of @slot
   rules determines the order of the boxes in the pagination template. @slot
   rules can define a name for the slot.

  <p>Slots default to displaying the content of the paginated element. Slots
   can instead contain generated content assigned with the content property.
   Slots can also be assigned content from named flows.

  <div class=example>
   <p>An @template rule that creates header and footer slots around the
    paginated element's content

   <pre>
    @template paged-display {
      @slot header { content: "header string"; }
      @slot content { }
      @slot footer { content: "footer string"; }
    }
    </pre>
  </div>

  <p>If any slot in a particular page has overflow content, a new page is
   created with a new set of slots to receive the overflow content. Slots
   with the same named flow assignment form a region chain (within a
   pagination template and/or across pages created from pagination
   templates). When a new page is created a slot that has been assigned
   element content or content from a named flow may not have any content left
   to render. In this case the slot for the exhausted content source is not
   instantiated.

  <div class=issue-marker>
   <div class=issue-details>If there is more than one slot with no ‘<code
    class=property>content</code>’ or ‘<code
    class=property>flow-from</code>’ assignment, does the element's content
    use all of these slots like a region chain, or is only the last
    unassigned slot used for content?</div>
  </div>

  <div class=example>
   <p>The simplest example takes all of the content in the document and flows
    it into a single pagination template with a single slot. This template
    will display a viewport's worth of content at a time, and will create a
    new slot on a new page each time content overflows.

   <p>The three examples below are equivalent, but merely illustrate how
    content from the element can be assigned to pagination template slots.
    Actual use of templates would either define more slots or assign content
    differently than the default.

   <pre class=separate-pre>
    body { overflow-style: paged-x; }</pre>

   <pre class=separate-pre>
    body { overflow-style: paged-x; }
    @template paged-display {
      @slot content { }
    }</pre>

   <pre class=separate-pre>
    body { overflow-style: paged-x; }
    body > * { flow-into: body-flow; }
    @template paged-display {
      @slot content { flow-from: body-flow; }
    }</pre>
  </div>

  <div class=issue-marker>
   <div class=issue-details>
    <p>@slot rules are a first pass at defining CSS-created boxes. Other
     means of creating and addressing pseudo-element slots have been
     discussed on www-style. If @slot rules or pseudo-elements are used to
     create template boxes, then OM for pseudo-elements must be defined
     (scripting and events working with paginated content is a valid use
     case).

    <p>One argument against using pseudo-elements to create templates is that
     this is defining structure in CSS. If nested slots are required, then
     we're on a slippery slope towards re-inventing HTML inside of CSS.

    <p>An alternative could use Shadow DOM to define the boxes. This gives us
     structure and OM, but would need a declarative method of mapping content
     to elements. One suggestion was to use @slot rules in a flat list for
     the simple case, but start to rely on Shadow DOM for more complicated
     cases. If this route is taken, then @slot rules probably aren't
     required, as Shadow DOM can also handle the flat list case.
   </div>
  </div>

  <p>Pagination templates can use declarations to determine the layout method
   for slots. @slot rules can use sizing and positioning declarations.

  <div class=example>
   <p>A pagination template could contain two side-by-side slots that
    paginate two separate articles. Side-by-side translations are often laid
    out this way. This example fills the left side of the paged view with
    content from an English article and the right side with content from a
    French article. New pages and slots are created until the content from
    both articles is exhausted. If one article is longer than the other then
    in this simple example template the longer article will continue taking
    up just its half of the page.

   <p> <img alt="side-by-side flows on a page"
    src="images/side-by-side-1.png" width=120> <span
    style="font-size:50px">…</span> <img
    alt="side-by-side flows with the left ending"
    src="images/side-by-side-2.png" width=120> <img alt="only the right flow"
    src="images/only-one-side-3.png" width=120> <span
    style="font-size:50px">…</span>

   <pre>
    body { overflow-style: paged-x; }
    .english { flow-into: english-flow; }
    .french { flow-into: french-flow; }
    @template side-by-side {
      @slot left {
        flow-from: english-flow;
        width: 40%;
        height: 90%;
        padding: 5%;
        float: left;
      }
      @slot right {
        flow-from: french-flow;
        width: 40%;
        height: 90%;
        padding: 5%
        float: right;
      }
    }
    &lt;body&gt;
      &lt;article class='english'&gt;...content...&lt;/article&gt;
      &lt;article class='french'&gt;...contenu...&lt;/article&gt;
    &lt;/body&gt;
    </pre>
  </div>

  <div class=example>
   <p>The example above could position the slots using grid layout rather
    than floats. In this simple example the longer article will take up the
    entire page once the shorter article is exhausted.

   <p> <img alt="side-by-side flows on a page"
    src="images/side-by-side-1.png" width=120> <span
    style="font-size:50px">…</span> <img
    alt="side-by-side flows with the left ending"
    src="images/side-by-side-2.png" width=120> <img
    alt="the right flow takes up the whole page" src="images/whole-page.png"
    width=120> <span style="font-size:50px">…</span>

   <pre>
    body { overflow-style: paged-x; }
    .english { flow-into: english-flow; }
    .french { flow-into: french-flow; }
    @template side-by-side {
      display: grid;
      grid-columns: 1fr 1fr;
      @slot left {
        flow-from: english-flow;
        padding: 5%;
        grid-column: 1;
      }
      @slot right {
        flow-from: french-flow;
        padding: 5%
        grid-column: 2;
      }
    }
    &lt;body&gt;
      &lt;article class='english'&gt;...content...&lt;/article&gt;
      &lt;article class='french'&gt;...contenu...&lt;/article&gt;
    &lt;/body&gt;
    </pre>
  </div>

  <h2 id=conditional-templates><span class=secno>3. </span>Template Selection</h2>

  <p>Multiple templates can be defined for a single document. An element that
   uses pagination templates either selects a template from the entire
   document set or a subset defined by the ‘<code
   class=property>template-set</code>’ property. Each page view created
   uses a single template. This template can be chosen from the applicable
   set using a selector, by matching content to display using the ‘<code
   class=property>required-flow</code>’ or ‘<code
   class=property>available-content</code>’ declarations, or just taking
   the last template found.

  <div class=issue-marker>
   <div class=issue-details>The following section describes selecting
    templates with several mechanisms (selectors and declarations, and
    presumably @template rules could be scoped by media queries). An
    alternative could be to define all selection mechanisms like a media
    query, where all of the selection mechanisms are outside the declaration
    block. Attempting to define template rejection rather than selection
    might also prove fruitful.</div>
  </div>

  <div class=example>
   <p>In this example the divs are paginated using the last template found
    from the set of templates that apply to the div. The first div uses
    template three, the second div uses template two, and the third div uses
    template one.

   <pre>
    div { overflow-style: paged-x; }
    .either-one-or-two { template-set: one two; }
    .only-one { template-set: one; }

    @template one { ... }
    @template two { ... }
    @template three { ... }

    &lt;div class='any-template'&gt; ... &lt;/div&gt;
    &lt;div class='either-one-or-two'&gt; ... &lt;/div&gt;
    &lt;div class='only-one'&gt; ... &lt;/div&gt;
    </pre>
  </div>

  <h3 id=ordered-templates><span class=secno>3.1. </span>Selecting Templates
   by Page Order</h3>

  <p>Selectors such as :first can be used on a pagination template to define
   a separate template for pages that match the selector.

  <div class="issue-marker wrapper">
   <div class=issue-marker>
    <div class=issue-details>Should :left and :right be allowed with a way of
     displaying more than one page at a time in a viewport? Should :nth(x)
     selectors be allowed?</div>
   </div>

   <div class=issue-marker>
    <div class=issue-details>Describe how @template rules cascade with names
     and selectors (or how they do not cascade, if that's preferable).</div>
   </div>
  </div>

  <div class=example>
   <p>Any of the side-by-side two-article examples from the previous section
    could have an @template :first {} rule that defined a fancy layout for
    the first page.

   <pre>
    @template side-by-side:first {
      @slot left {
        //fancy styling
        flow-from: article1;
      }
      @slot right {
        //fancy styling
        flow-from: article2;
      }
    }
    </pre>
  </div>

  <div class="issue-marker wrapper">
   <div class=issue-marker>
    <div class=issue-details>define "fancy."</div>
   </div>

   <div class=issue-marker>
    <div class=issue-details>Depending on how template selection is defined,
     there will likely be scenarios where degenerate template sets can either
     fail to display all of the content or result in an infinite loop of page
     generation. This first draft falls into the latter category (make a
     :first template with a slot that overflows, but fail to include an
     assignment for that slot's content in all other templates), so this will
     need to be addressed with more selection rules.</div>
   </div>
  </div>

  <h3 id=selection-from-required-flows><span class=secno>3.2.
   </span>Selecting Templates from Required Flows</h3>

  <p>The ‘<code class=property>required-flow</code>’ property can be used
   in a pagination template to list named flows that must still have content
   in order for the template to be used. If more than one template has a
   ‘<code class=property>required-flow</code>’ value that matches the
   remaining flow content, the last template that matches will be used.

  <div class=example>
   <p>"Continued on" layout.

   <p>These pagination templates will display an initial page with the
    beginning of both the ‘<code class=property>lead-story</code>’ flow
    and a ‘<code class=property>related-article</code>’ flow. If the lead
    story has more content than will fit on that first page, the next page(s)
    will show only content from that lead story. When the content from the
    lead story is exhausted, then pages will follow with content from the
    related article.

   <p> <img alt="side-by-side flows on a page"
    src="images/side-by-side-1.png" width=120> <img
    alt="columns continuing just the first flow"
    src="images/first-article-columns.png" width=120> <span
    style="font-size:50px">…</span> <img
    alt="columns ending the first flow" src="images/first-article-end.png"
    width=120> <img alt="columns continuing the second flow"
    src="images/second-article-columns.png" width=120> <span
    style="font-size:50px">…</span>

   <pre>
    body { overflow-style: paged-x; }
    .lead-story { flow-into: lead-flow; }
    .related-article { flow-into: related-flow; }
    @template related {
      required-flow: related-flow;
      @slot content {
        flow-from: related-flow;
        column-width: 20em;
      }
    }
    @template lead {
      required-flow: lead-flow;
      @slot content {
        flow-from: lead-flow;
        column-width: 20em;
      }
    }
    @template continued-on:first {
      @slot lead {
        flow-from: lead-flow;
        width: 40%;
        height: 90%;
        padding: 5%;
        float: left;
      }
      @slot related {
        flow-from: related-flow;
        width: 40%;
        height: 90%;
        padding: 5%
        float: left;
      }
    }
    &lt;body&gt;
      &lt;article class='lead-story'&gt;...content...&lt;/article&gt;
      &lt;article class='related-article'&gt;...content...&lt;/article&gt;
    &lt;/body&gt;
    </pre>
  </div>

  <h3 id=selection-from-available-content><span class=secno>3.3.
   </span>Selecting Templates from Available Content</h3>

  <p>Pagination templates can be selected based on the order of content in
   the DOM tree. Content may be split out into one or more named flows, but
   the original order can be discovered in the DOM and used for template
   selection.

  <p>Pagination templates have a ‘<code class=property>primary</code>’
   content flow. The primary flow for a pagination template is usually the
   content of the paginated element. If no slot in the template displays the
   element contents, then the primary flow of the pagination template is the
   first named flow in its required-flow declaration.

  <p>When selecting the pagination template for the next page, the primary
   flow in the original markup can be scanned to determine whether any
   out-of-flow content in other named flows was originally related to the
   next page of primary flow. If this is the case, then those named flows
   have ‘<code class=property>available</code>’ content for the purpose
   of selecting an appropriate template that can display this content.

  <p>Pagination templates can have an ‘<code
   class=property>available-content</code>’ declaration listing the named
   flows that must have available content for the template to be selected.
   Templates with more ‘<code class=property>available-content</code>’
   flow matches take precedence over fewer or no ‘<code
   class=property>available-content</code>’ flow matches. If a template
   with an ‘<code class=property>available-content</code>’ declaration is
   chosen, only the available content in those flows is displayed in the
   slots associated with those flows.

  <div class=example>
   <p>Clarification example (not meant to be a valid use case)

   <p>Consider an article element that contains images scattered throughout.
    Assign the images to a flow named ‘<code
    class=property>images</code>’ and the rest of the article to a flow
    named ‘<code class=property>text</code>’. Then define two pagination
    templates - one that has slots only for the ‘<code
    class=property>text</code>’ flow, and another that has slots for both
    the ‘<code class=property>text</code>’ and ‘<code
    class=property>images</code>’ flows. Both templates require the
    ‘<code class=property>text</code>’ flow, but the second template also
    requires the ‘<code class=property>images</code>’ flow and has an
    ‘<code class=property>available-content</code>’ declaration listing
    the ‘<code class=property>images</code>’ flow. Each time a page is
    laid out, the original article element is scanned to see whether an image
    element is in the next page's worth of content (determined by some
    DOM-tree-scanning heuristic – not layout). If so, then that content
    from the ‘<code class=property>images</code>’ flow is available for
    the purpose of selecting a template.
  </div>

  <div class=example>
   <p>Motivational example (meant as a use case)

   <p>Assume you have an article that contains both pull quotes and images.
    If only images <em>or</em> pull quotes would occur on a page, position
    those elements in the center right of the template. But if both images
    <em>and</em> pull quotes would appear, position the images in the top
    left and the pull quotes in the bottom right.

   <div class=issue-marker>
    <div class=issue-details>code this example</div>
   </div>
  </div>

  <h2 id=cssom><span class=secno>4. </span>CSS Object Model</h2>

  <div class=issue-marker>
   <div class=issue-details>There should be extensive OM defined to access
    pages and slots. What page is being displayed should be available. Pages
    and slots should accept event handlers. Anchors should navigate to the
    appropriate page (as should search). What content fits in each slot and
    page should be determinable. Lots to fill out here.</div>
  </div>

  <div class=example>
   <p>Motivational example

   <p>Given the side-by-side paginated template for French and English, allow
    the user to click and drag the French text from the right to the left to
    switch sides for both flows.
  </div>

  <h2 id=conformance><span class=secno>5. </span>Conformance</h2>

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

  <p>The editor is grateful to the CSS working group for their feedback and
   help with the genesis of this specification.

  <p>In addition, the editor would like to thank the following individuals
   for their contributions, either during the conception of CSS Pagination
   Templates or during its development and specification review process:

  <ul>
   <li>Rossen Atanassov

   <li>Tab Atkins

   <li>Razvan Caliman

   <li>Alexandru Chiculita

   <li>Sylvain Galineau

   <li>Vincent Hardy

   <li>David Hyatt

   <li>Brad Kemper

   <li>Håkon Wium Lie

   <li>Alex Mogilevsky

   <li>Christoph Päper

   <li>Peter Sorotokin

   <li>Stephen Zilles
  </ul>

  <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><!---->
  </dl>
  <!--end-normative-->

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

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

   <dt id=CSS3-REGIONS>[CSS3-REGIONS]

   <dd>Vincent Hardy; Rossen Atanassov; Alan Stearns. <a
    href="http://www.w3.org/TR/2013/WD-css3-regions-20130528/"><cite>CSS
    Regions Module Level 1.</cite></a> 28 May 2013. W3C Working Draft. (Work
    in progress.) URL: <a
    href="http://www.w3.org/TR/2013/WD-css3-regions-20130528/">http://www.w3.org/TR/2013/WD-css3-regions-20130528/</a>
   </dd>
   <!---->

   <dt id=CSS3GCPM>[CSS3GCPM]

   <dd>Håkon Wium Lie. <a
    href="http://www.w3.org/TR/2011/WD-css3-gcpm-20111129/"><cite>CSS
    Generated Content for Paged Media Module.</cite></a> 29 November 2011.
    W3C Working Draft. (Work in progress.) URL: <a
    href="http://www.w3.org/TR/2011/WD-css3-gcpm-20111129/">http://www.w3.org/TR/2011/WD-css3-gcpm-20111129/</a>
   </dd>
   <!---->

   <dt id=CSS3GRID>[CSS3GRID]

   <dd>Alex Mogilevsky; Markus Mielke. <a
    href="http://www.w3.org/TR/2007/WD-css3-grid-20070905"><cite>CSS Grid
    Positioning Module Level 3.</cite></a> 5 September 2007. W3C Working
    Draft. (Work in progress.) URL: <a
    href="http://www.w3.org/TR/2007/WD-css3-grid-20070905">http://www.w3.org/TR/2007/WD-css3-grid-20070905</a>
   </dd>
   <!---->
  </dl>
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