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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://www.w3.org/2006/03/hcard"><meta content="text/html;
charset=utf-8" http-equiv=Content-Type>
<title>CSS Line Grid Module</title>
<link href="../default.css" rel=stylesheet type="text/css">
<link href="http://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
type="text/css">
<style type="text/css">
</style>
<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 Line Grid Module</h1>
<h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 28 April 2011</h2>
<dl>
<dt>This version:
<dd><a href="http://www.w3.org/TR/2011/ED-unknown-shortname-20110428">
http://www.w3.org/TR/2011/ED-unknown-shortname-20110428</a> <!--
<dt>Latest version:
<dd><a href="http://www.w3.org/TR/css-line-grid">
http://www.w3.org/TR/css-line-grid</a>
<dt>Previous version:
<dd><a href="http://www.w3.org/PreviousVersionURI">
http://www.w3.org/PreviousVersionURI</a>
-->
<dt>Editors:
<dd class=vcard><span class=fn>Koji Ishii</span>, <span class=org>Invited
Expert</span>, <span class=email><a
href="mailto:kojiishi@gluesoft.co.jp">kojiishi@gluesoft.co.jp</a></span>
</dl>
<!--begin-copyright-->
<p class=copyright><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> © 2011 <a
href="http://www.w3.org/"><acronym title="World Wide Web
Consortium">W3C</acronym></a><sup>®</sup> (<a
href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute
of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym
title="European Research Consortium for Informatics and
Mathematics">ERCIM</acronym></a>, <a
href="http://www.keio.ac.jp/">Keio</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>CSS is a language for describing the rendering of structured documents
(such as HTML and XML) on screen, on paper, in speech, etc. This module
contains the features of CSS level 3 relating to <var
class=issue>DESCRIBE HERE</var>. It includes and extends the functionality
of CSS level 2 <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{CSS21}}--></a>, which builds on CSS
level 1 <a href="#CSS1" rel=biblioentry>[CSS1]<!--{{CSS1}}--></a>.
The main extensions compared to level 2 are <var
class=issue>SUMMARIZE HERE</var>.
<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=%5Bunknown-shortname%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
“unknown-shortname” in the subject, preferably like this:
“[<!---->unknown-shortname<!---->] <em>…summary of
comment…</em>”
<p>This document was produced by the <a href="/Style/CSS/members">CSS
Working Group</a> (part of the <a href="/Style/">Style Activity</a>).
<p>This document was produced by a group operating under the <a
href="/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent
Policy</a>. W3C maintains a <a href="/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="/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a
href="/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the
W3C Patent Policy</a>.</p>
<!--end-status-->
<p>The following features are at risk: …
<h2 class="no-num no-toc" id=contents>Table of contents</h2>
<!--begin-toc-->
<ul class=toc>
<li><a href="#introduction"><span class=secno>1. </span>Introduction</a>
<ul class=toc>
<li><a href="#context"><span class=secno>1.1. </span>Background</a>
<li><a href="#placement"><span class=secno>1.2. </span>Module
Interactions</a>
<li><a href="#conventions"><span class=secno>1.3. </span>Document
Conventions</a>
<li><a h
72A1
ref="#values"><span class=secno>1.4. </span>Values</a>
</ul>
<li><a href="#defining-grids"><span class=secno>2. </span>Defining
Grids</a>
<ul class=toc>
<li><a href="#layout-grid-line-prop"><span class=secno>2.1.
</span>Define Line Grids: the ‘<code
class=property>layout-grid-line</code>’ property</a>
</ul>
<li><a href="#using-grids"><span class=secno>3. </span>Using Grids</a>
<ul class=toc>
<li><a href="#layout-grid-mode-prop"><span class=secno>3.1. </span>Grid
Mode: the ‘<code class=property>layout-grid-mode</code>’
property</a>
<li><a href="#grid-shorthand-the-layout-grid-property"><span
class=secno>3.2. </span>Grid Shorthand: the ‘<code
class=property>layout-grid</code>’ property</a>
<li><a href="#grid-length-unit"><span class=secno>3.3. </span>The
‘<code class=css>gd</code>’ length unit</a>
<li><a href="#round-length"><span class=secno>3.4. </span>Rounding Down
to Multiple of Units: ‘<code class=css>*gd</code>’ and
‘<code class=css>*em</code>’</a>
</ul>
<li><a href="#conformance"><span class=secno>4. </span> Conformance</a>
<ul class=toc>
<li><a href="#conformance-classes"><span class=secno>4.1. </span>
Conformance Classes</a>
<li><a href="#partial"><span class=secno>4.2. </span> Partial
Implementations</a>
<li><a href="#experimental"><span class=secno>4.3. </span> Experimental
Implementations</a>
<li><a href="#cr-exit-criteria"><span class=secno>4.4. </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-->
<h2 id=introduction><span class=secno>1. </span>Introduction</h2>
<h3 id=context><span class=secno>1.1. </span>Background</h3>
<p><em>This section is not normative.</em>
<p>This specification provides features to align lines and blocks to
invisible grids in the document.
<p>Alinging lines and blocks to grids gives the following benefits:
<ul>
<li>Keep vertical rhythm for better readability.
<li>Align lines between columns in multi-column documents.
<li>Layout lines at the same position in every page in paged media.
Keeping the position of the bottom line of a page has benefits for design
and readability. This also results better readability on duplex printing,
two pages spreads, or when displaying on slow display devices like e-ink.
<li>East Asian layouts require the use of vertical rhythm more often than
other scripts does, even in single column, non-paged media documents, as
defined in <a href="#JLREQ" rel=biblioentry>[JLREQ]<!--{{JLREQ}}--></a>.
<li>In East Asian documents, it is often desirable to make the line width
to be multiple of <em>em</em>. Most East Asian characters have 1em
advance, and most East Asian documents are justified, so this minimizes
the case where justification needs to expand lines.
</ul>
<p>There are several types of objects in a document that can break the
vertical rhythm. Examples include lines in different size of text,
pictures, and tables.
<div class=figure> <img alt="Keep vertical rhythm through pictures and
different size of text in a multi-column document" height=246
src=line-grid-multicol.png width=480>
<p class=caption>Keep vertical rhythm through pictures and different size
of text in a multi-column document.</p>
</div>
<p>This module defines following capabilities:
<ul>
<li>Defines grids in the line progression direction.
<li>Controls how lines and blocks align to the grids.
<li>Rounds lengths down to the mulitple of units.
</ul>
<p>It is important to control these capabilities independently, so that
align to grids can be turned off for tables for example, but can be turned
back on for the following text to the original grids.
<h3 id=placement><span class=secno>1.2. </span>Module Interactions</h3>
<p class=issue>Explain, normatively, how this module affects the definition
of CSS.
<p>This module replaces and extends the <var class=issue>SUMMARIZE
HERE</var> features defined in <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a> sections <var class=issue>W.X
and Y.Z</var>.
<h3 id=conventions><span class=secno>1.3. </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="#RFC2119" rel=biblioentry>[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.</p>
</div>
<p>Informative notes begin with the word “Note” and are set apart from
the normative text with <code>class="note"</code>, like this:
<p class=note>Note, this is an informative note.
<h3 id=values><span class=secno>1.4. </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="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>. Value types not defined in
this specification are defined in CSS Level 2 Revision 1 <a
href="#CSS21" rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>. Other CSS
modules may expand the definitions of these value types: for example <a
href="#CSS3COLOR" rel=biblioentry>[CSS3COLOR]<!--{{CSS3COLOR}}--></a>,
when combined with this module, expands the definition of the
<color> 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=defining-grids><span class=secno>2. </span>Defining Grids</h2>
<h3 id=layout-grid-line-prop><span class=secno>2.1. </span>Define Line
Grids: the ‘<a href="#layout-grid-line"><code
class=property>layout-grid-line</code></a>’ property</h3>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=layout-grid-line>layout-grid-line</dfn>
<tr>
<th>Value:
<td>none | auto | <length> | <percentage>
<tr>
<th>Initial:
<td>none
<tr>
<th>Applies to:
<td>block containers
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>specified value
</table>
<p class=issue>TBD: I expect this to be very similar to the one in <a
href="http://www.w3.org/TR/2001/WD-css3-text-20010517/#layout-grid-line-prop">CSS3
module: text WD 20010517</a>.
<p class=issue>Grid origin should be defined by the element that has this
property. In that case, should it inherit, or not inherit value but
inherit grid?
<h2 id=using-grids><span class=secno>3. </span>Using Grids</h2>
<h3 id=layout-grid-mode-prop><span class=secno>3.1. </span>Grid Mode: the
‘<a href="#layout-grid-mode"><code
class=property>layout-grid-mode</code></a>’ property</h3>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=layout-grid-mode>layout-grid-mode</dfn>
<tr>
<th>Value:
<td>none | block | line
<tr>
<th>Initial:
<td>none
<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 controls how lines and blocks are aligned to grids. Values
have the following meanings:
<dl>
<dt><dfn id=none title="layout-grid-mode::none">‘<code
class=css>none</code>’</dfn>
<dd>Do not align any objects to the grids.
<dt><dfn id=block title="layout-grid-mode::block">‘<code
class=css>block</code>’</dfn>
<dd>Align blocks to the line grids. <!--
The height of the block in this definition includes margins.
-->
The height includes paddings and borders, but not margins. Increasing
heights to fit to grids is done by adding to computed margins.
<dt><dfn id=line title="layout-grid-mode::line">‘<code
class=css>line</code>’</dfn>
<dd>Align line boxes to the line grids. <!--
The line in this definition is a line box
with before margin included if it is the first line of a block,
and with after margin if last.
-->
The height is the height of the line box. Increasing heights to fit to
grids is done by increasing the computed height of the line box.
</dl>
<p class=issue>Handling margins and borders needs review
<p>When this property is set to anything other than ‘<code
class=css>none</code>’, the object to align is vertically centered
within the grid row. If the computed height is larger than the grid space,
then the object is centered within the smallest number of grid rows
necessary for the object to fit in. The starting alignment point is moved
accordingly. This is illustrated below, where <em>a</em> represents the
numerical ‘<a href="#layout-grid-line"><code
class=property>layout-grid-line</code></a>’ value, <em>b</em> and
<em>c</em> are half the difference between the computed line-heights and
either the layout-grid-line value or twice the value respectively.:
<div class=figure> <img src=lgl.gif>
<p class=caption>Layout of contents within line grid, where <em>a</em>
represents the layout-grid-line value, and the alignment baseline is at
the bottom (after-edge).</p>
</div>
<p>As for regular height computation, the ruby box is treated especially.
In a similar fashion to the line-height determination process, only the
ruby base element is considered for centering purpose, however the above
and/or the after space should be sufficient to fit the ruby text above
and/or after the base text within the grid-line space. If this is not the
case, the grid-line size needs to be increased in multiple of grid rows
until the whole ruby box fits. <span class=issue>Is just ignoring ruby
text enough? like rt { layout-grid-mode: ignore; } or nothing needed to be
defined if line-stacking-ruby: auto does the work?</span>
<p>Note that in order for this property to have an effect, line grids must
be defined by the ‘<a href="#layout-grid-line"><code
class=property>layout-grid-line</code></a>’ property.
<div class=example>
<div class=sidefigure> <img alt="Large text wraps within line grids"
height=244 src=line-grid-wrap.png width=276>
<p class=caption>Large text wraps within line grids.</p>
</div>
<p>When a different size of text like headings wraps, it is usually
aligned to grids as a block and lines within the block do not align.</p>
<p>This effect can be achieved by the following code:</p>
<pre><code class=css>
<!-- -->body { line-grid-mode: line; }
<!-- -->h1 { line-grid-mode: block; }
<!-- --></code></pre>
<br style="clear:both;">
</div>
<h3 id=grid-shorthand-the-layout-grid-property><span class=secno>3.2.
</span>Grid Shorthand: the ‘<code
class=property>layout-grid</code>’ property</h3>
<p class=issue>TBD
<h3 id=grid-length-unit><span class=secno>3.3. </span>The ‘<code
class=css><span class=index id=gd title="length
unit::gd">gd</span></code>’ length unit</h3>
<p>The existence of a grid in an element makes it possible and very useful
to express various measurements in that element in terms of grid units.
Grid units are used very frequently in East Asian typography, especially
for the left, right, top and bottom element margins.
<p>Therefore a new length unit is necessary: gd to enable the author to
specify the various measurements in terms of the grid.
<p>For example, consider the following style:
<pre><code class=css>P { layout-grid: strict both 20pt 15pt; margin: 1gd 3gd 1gd 2gd }</code></pre>
<p>This way, all P elements would effectively acquire a 15pt top margin, a
60pt right margin, a 15pt bottom margin and a 40pt left margin.
<p>If no grid is specified, the gd unit should be treated the same as the
em unit.
<p class=issue>Just copied from old WD, need to refresh
<h3 id=round-length><span class=secno>3.4. </span>Rounding Down to Multiple
of Units: ‘<code class=css><span class=index id=gd0 title="length
unit::*gd">*gd</span></code>’ and ‘<code class=css><span
class=index id=em title="length unit::*em">*em</span></code>’</h3>
<p>The ‘<code class=property>width</code>’ and ‘<code
class=property>height</code>’ properties accept ‘<code
class=css>*gd</code>’ and ‘<code class=css>*em</code>’
values. These values compute to ‘<code class=css>auto</code>’,
and then the result will be round down to the largest multiple of the
specified unit that is equal to or less than the original computed value.
<p>The fraction is distributed evenly to each side margins. If it is used
for ‘<code class=property>height</code>’, the half of fraction
is added to the top and bottom margins, and if for ‘<code
class=property>width</code>’, to the left and right margins.
<p class=issue>Should this be a property instead?
<h2 id=conformance><span class=secno>4. </span> Conformance</h2>
<h3 id=conformance-classes><span class=secno>4.1. </span> Conformance
Classes</h3>
<p>Conformance to <var class=issue>CSS TEMPLATE Module</var> 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 <var class=issue>CSS TEMPLATE
Module</var> if all of its declarations that use properties defined in
this module have values that are valid according to the generic CSS
grammar and the individual grammars of each property as given in this
module.
<p>A renderer is conformant to <var class=issue>CSS TEMPLATE Module</var>
if, in addition to interpreting the style sheet as defined by the
appropriate specifications, it supports all the properties defined by <var
class=issue>CSS TEMPLATE Module</var> 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 <var class=issue>CSS TEMPLATE
Module</var> if it writes syntactically correct style sheets, according to
the generic CSS grammar and the individual grammars of each property in
this module.
<h3 id=partial><span class=secno>4.2. </span> Partial Implementations</h3>
<p>So that authors can exploit the forward-compatible parsing rules to
assign fallback values, CSS renderers <strong>must</strong> treat as
invalid (and <a
href="http://www.w3.org/TR/CSS21/conform.html#ignore">ignore as
appropriate</a>) any at-rules, properties, property values, keywords, and
other syntactic constructs for which they have no usable level of support.
In particular, user agents <strong>must not</strong> selectively ignore
unsupported component values and honor supported values in a single
multi-value property declaration: if any value is considered invalid (as
unsupported values must be), CSS requires that the entire declaration be
ignored.
<h3 id=experimental><span class=secno>4.3. </span> Experimental
Implementations</h3>
<p>To avoid clashes with future CSS features, the CSS specifications
reserve a <a
href="http://www.w3.org/TR/CSS21/syndata.html#vendor-keywords">prefixed
syntax</a> for proprietary property and value extensions to CSS. The CSS
Working Group recommends that experimental implementations of features in
CSS Working Drafts also use vendor-prefixed property or value names. This
avoids any incompatibilities with future changes in the draft. Once a
specification reaches the Candidate Recommendation stage, implementors
should implement the non-prefixed syntax for any feature they consider to
be correctly implemented according to spec.
<h3 id=cr-exit-criteria><span class=secno>4.4. </span> CR Exit Criteria</h3>
<p class=issue>[Change or remove the following CR exit criteria if the spec
is not a module, but, e.g., a Note or a profile. This text was <a
href="/Style/CSS/Tracker/actions/44"> decided on 2008-06-04.</a>]
1891
<p id=cr-exit-criteria> 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=issue>[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 style="display: none"><!-- keeps the doc valid if the DL is empty -->
<!---->
<dt id=CSS21>[CSS21]
<dd>Bert Bos; et al. <a
href="http://www.w3.org/TR/2009/CR-CSS2-20090423"><cite>Cascading Style
Sheets Level 2 Revision 1 (CSS 2.1) Specification.</cite></a> 23
April 2009. W3C Candidate Recommendation. (Work in progress.) URL: <a
href="http://www.w3.org/TR/2009/CR-CSS2-20090423">http://www.w3.org/TR/2009/CR-CSS2-20090423</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 style="display: none"><!-- keeps the doc valid if the DL is empty -->
<!---->
<dt id=CSS1>[CSS1]
<dd>Håkon Wium Lie; Bert Bos. <a
href="http://www.w3.org/TR/2008/REC-CSS1-20080411"><cite>Cascading Style
Sheets (CSS1) Level 1 Specification.</cite></a> 11 April 2008. W3C
Recommendation. URL: <a
href="http://www.w3.org/TR/2008/REC-CSS1-20080411">http://www.w3.org/TR/2008/REC-CSS1-20080411</a>
</dd>
<!---->
<dt id=CSS21>[CSS21]
<dd>Bert Bos; et al. <a
href="http://www.w3.org/TR/2009/CR-CSS2-20090423"><cite>Cascading Style
Sheets Level 2 Revision 1 (CSS 2.1) Specification.</cite></a> 23
April 2009. W3C Candidate Recommendation. (Work in progress.) URL: <a
href="http://www.w3.org/TR/2009/CR-CSS2-20090423">http://www.w3.org/TR/2009/CR-CSS2-20090423</a>
</dd>
<!---->
<dt id=CSS3COLOR>[CSS3COLOR]
<dd>Tantek Çelik; Chris Lilley; L. David Baron. <a
href="http://www.w3.org/TR/2010/PR-css3-color-20101028"><cite>CSS Color
Module Level 3.</cite></a> 28 October 2010. W3C Proposed Recommendation.
(Work in progress.) URL: <a
href="http://www.w3.org/TR/2010/PR-css3-color-20101028">http://www.w3.org/TR/2010/PR-css3-color-20101028</a>
</dd>
<!---->
<dt id=JLREQ>[JLREQ]
<dd>Yasuhiro Anan; et al. <a
href="http://www.w3.org/TR/2009/NOTE-jlreq-20090604/"><cite>Requirements
for Japanese Text Layout.</cite></a> 4 June 2009. W3C Working Group Note.
URL: <a
href="http://www.w3.org/TR/2009/NOTE-jlreq-20090604/">http://www.w3.org/TR/2009/NOTE-jlreq-20090604/</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="authoring
tool"><strong>4.1.</strong></a>
<li>layout-grid-line, <a href="#layout-grid-line"
title=layout-grid-line><strong>2.1.</strong></a>
<li>layout-grid-mode, <a href="#layout-grid-mode"
title=layout-grid-mode><strong>3.1.</strong></a>
<ul>
<li>block, <a href="#block" title="layout-grid-mode,
block"><strong>3.1.</strong></a>
<li>line, <a href="#line" title="layout-grid-mode,
line"><strong>3.1.</strong></a>
<li>none, <a href="#none" title="layout-grid-mode,
none"><strong>3.1.</strong></a>
</ul>
<li>length unit
<ul>
<li>*em, <a href="#em" title="length unit, *em">3.4.</a>
<li>gd, <a href="#gd" title="length unit, gd">3.3.</a>
<li>*gd, <a href="#gd0" title="length unit, *gd">3.4.</a>
</ul>
<li>renderer, <a href="#renderer" title=renderer><strong>4.1.</strong></a>
<li>style sheet
<ul>
<li>as conformance class, <a href="#style-sheet" title="style sheet, as
conformance class"><strong>4.1.</strong></a>
</ul>
</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 valign=baseline>
<td><a class=property href="#layout-grid-line">layout-grid-line</a>
<td>none | auto | <length> | <percentage>
<td>none
<td>block containers
<td>no
<td>N/A
<td>visual
<tr valign=baseline>
<td><a class=property href="#layout-grid-mode">layout-grid-mode</a>
<td>none | block | line
<td>none
<td>block containers
<td>yes
<td>N/A
<td>visual
</table>
<!--end-properties-->
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