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<!DOCTYPE html>
<html lang=en>
<head><meta content="text/html; charset=utf-8" http-equiv=Content-Type>
<title>CSS Mobile Text Size Adjustment Module Level 1</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">
<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 Mobile Text Size Adjustment Module Level 1</h1>
<h2 class="no-num no-toc" id=longstatus-date>Editor's Draft 29 March 2012</h2>
<dl>
<dt>This version:
<dd><a
href="http://www.w3.org/TR/2012/ED-css-size-adjust-20120329/">http://www.w3.org/TR/2012/ED-css-size-adjust-20120329/</a>
<dt>Latest version:
<dd><a
href="http://www.w3.org/TR/css-size-adjust/">http://www.w3.org/TR/css-size-adjust/</a>
<dt>Editor's draft:
<dd><a
href="http://dev.w3.org/csswg/css-size-adjust/">http://dev.w3.org/csswg/css-size-adjust/</a>
<dt>Previous version:
<dd>none
<dt>Issue Tracking:
<dd>Maintained in document (only editor's draft is current)
<dt>Feedback:
<dd><a href="mailto:www-style@w3.org?subject=%5Bcss-size-adjust%5D%20feedback">www-style@w3.org</a>
with subject line “<kbd>[css-size-adjust] <var>… message topic …</var></kbd>”
(<a rel="discussion" href="http://lists.w3.org/Archives/Public/www-style/">archives</a>)
<dt>Editors:
<dd class=vcard><a class="fn n url" href="http://dbaron.org/"><abbr
class=given-name>L.</abbr> <span class=additional-name>David</span>
<span class=family-name>Baron</span></a> (<span
class="org company vcard"><a class="company fn org url"
href="http://www.mozilla.org/">Mozilla Corporation</a></span>)
<dd class=vcard><a class="fn url" href="http://tantek.com/"
lang=tr>Tantek Çelik</a> (<span class="org company vcard"><a
class="company fn org url" href="http://www.mozilla.org/">Mozilla
Corporation</a></span>)
</dl>
<!--begin-copyright-->
<p class=copyright><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> © 2012 <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>), 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 features of CSS relating to one possible mechanism for adapting
pages designed for desktop computer displays for display on smaller
screens such as those of mobile phones. This mechanism involves displaying
a scaled down display of the Web page and allowing the user to pan and
zoom within that display, but within that scaled down display making
certain text and similar elements larger than specified by the page author
in order to ensure that when a block of wrapped text is zoomed to the
width of the device (so it can be read without side-to-side scrolling for
each line), the text is large enough to be readable.
<h2 class="no-num no-toc" id=status>Status of this document</h2>
<!--begin-status-->
<p>This is a public copy of the editors' draft. It is provided for
discussion only and may change at any moment. Its publication here does
not imply endorsement of its contents by W3C. Don't cite this document
other than as work in progress.
<p>The (<a
href="http://lists.w3.org/Archives/Public/www-style/">archived</a>) public
mailing list <a
href="mailto:www-style@w3.org?Subject=%5Bcss-size-adjust%5D%20PUT%20SUBJECT%20HERE">
www-style@w3.org</a> (see <a
href="http://www.w3.org/Mail/Request">instructions</a>) is preferred for
discussion of this specification. When sending e-mail, please put the text
“css-size-adjust” in the subject, preferably like this:
“[<!---->css-size-adjust<!---->] <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:
<ul>
<li>the <percentage> value for ‘<a
href="#text-size-adjust"><code
class=property>text-size-adjust</code></a>’
<li>the reference to <a href="#CSS3TEXT"
rel=biblioentry>[CSS3TEXT]<!--{{!CSS3TEXT}}--></a>'s ‘<code
class=property>text-wrap</code>’ property
</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>
</ul>
<li><a href="#default-adjustment"><span class=secno>2. </span>Default size
adjustment</a>
<ul class=toc>
<li><a href="#default-adjustment-types"><span class=secno>2.1.
</span>Types of boxes adjusted</a>
<li><a href="#default-adjustment-conditions"><span class=secno>2.2.
</span>Conditions that suppress adjustment</a>
<li><a href="#default-adjustment-calculation"><span class=secno>2.3.
</span>Calculation of default adjustment</a>
</ul>
<li><a href="#adjustment-control"><span class=secno>3. </span>Size
adjustment control: the ‘<code
class=property>text-size-adjust</code>’ property</a>
<li><a href="#conformance"><span class=secno>4. </span>Conformance</a>
<ul class=toc>
<li><a href="#conventions"><span class=secno>4.1. </span>Document
conventions</a>
<li><a href="#conformance-classes"><span class=secno>4.2.
</span>Conformance classes</a>
<li><a href="#partial"><span class=secno>4.3. </span>Partial
implementations</a>
<li><a href="#experimental"><span class=secno>4.4. </span>Experimental
implementations</a>
<li><a href="#testing"><span class=secno>4.5. </span>Non-experimental
implementations</a>
<li><a href="#cr-exit-criteria"><span clas
7803
s=secno>4.6. </span>CR exit
criteria</a>
</ul>
<li class=no-num><a href="#acknowledgments">Acknowledgments</a>
<li class=no-num><a href="#references">References</a>
<ul class=toc>
<li class=no-num><a href="#normative-references">Normative
references</a>
<li class=no-num><a href="#other-references">Other references</a>
</ul>
<li class=no-num><a href="#index">Index</a>
<li class=no-num><a href="#property-index">Property index</a>
</ul>
<!--end-toc-->
<h2 id=intro><span class=secno>1. </span>Introduction</h2>
<p>A common mechanism for displaying Web pages that were designed for large
desktop displays on much smaller displays such as those of mobile phones
involves allowing the user to pan and zoom around within a view of the Web
page drawn as though it were drawn into the width of a typical desktop Web
browser display. The ability to pan and zoom the page lets the user both
see an overview of the page and zoom in to specific parts to read or
interact with them.
<p>One common problem with this type of interaction occurs when the user
wants to read a large block of text. It might be that a block of text
within this desktop-formatted page might be laid out so that when the user
zooms in so that the text is large enough to read, each line of text is
wider than the display on the small device. This means the user needs to
scroll side to side to read <em>each line of text</em>, which is a serious
inconvenience to the user.
<p>One way for software that displays Web pages or other CSS-formatted
content on a mobile device is to make some of the text larger so that this
problem does not occur. The goal of this enlargement is to make the text
big enough so that when the block it is in is scaled to the width of the
display, the text is large enough to read. At the same time, this needs to
be done with minimal disruption to the overall design of the page.
<p>While implementations of CSS are not required to use this technique,
this module describes how implementations of CSS that do use this
technique must do so. In other words, while implementations of CSS are not
required to implement this module, this module nonetheless places
requirements on implementations of this module.
<p> This module describes how this size adjustment works and describes a
new CSS property that authors of CSS can use to provide hints to the
implementation about which text or other elements should or should not be
enlarged.
<h3 id=placement><span class=secno>1.1. </span>Module interactions</h3>
<p>This module adds additional features that are not defined in <a
href="#CSS21" rel=biblioentry>[CSS21]<!--{{CSS21}}--></a>. These features
may lead to a different size being computed than would be computed when
following <a href="#CSS21" rel=biblioentry>[CSS21]<!--{{CSS21}}--></a>
alone.
<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="#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=default-adjustment><span class=secno>2. </span>Default size
adjustment</h2>
<p>This section defines the default size adjustment rules. These rules are
then referenced by the definition of the ‘<a
href="#text-size-adjust"><code
class=property>text-size-adjust</code></a>’ property in the
following section.
<p class=issue>All of the subsections of this section need significant
refinement: additional detail, verification that the detail already
present is correct, etc.
<p class=issue>It's not clear how much this section should define precise
behavior versus how much it should allow future room for innovation and
improvement.
<h3 id=default-adjustment-types><span class=secno>2.1. </span>Types of
boxes adjusted</h3>
<p>The default size adjustment affects text and form controls, whether
those form controls contain text (e.g., text inputs, selects) or do not
(e.g., radio buttons, checkboxes).
<h3 id=default-adjustment-conditions><span class=secno>2.2.
</span>Conditions that suppress adjustment</h3>
<p>A number of conditions suppress the default adjustment because these
conditions are associated with layouts for which the user experience would
be worsened by size adjustment rather than improved by it. These
conditions are:
<ul>
<li>when the total amount of text in the block formatting context (see <a
href="#CSS21" rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>) (excluding
text inside descendant block formatting contexts) is approximately
smaller than the amount that would require wrapping to more than one or
two lines within that context's width,
<li>when the objects to be adjusted are inside a block-level or
‘<code class=css>display: inline-block</code>’ element with a
‘<code class=property>height</code>’ other than ‘<code
class=css>auto</code>’ (see <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>),
<li>when the objects to be adjusted are inside a ‘<code
class=css>display: inline-block</code>’ element with a ‘<code
class=property>width</code>’ other than ‘<code
class=css>auto</code>’ (see <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>),
<li>when the objects to be adjusted have ‘<code
class=property>white-space</code>’ of ‘<code
class=css>pre</code>’ or ‘<code
class=css>nowrap</code>’ (see <a href="#CSS21"
rel=biblioentry>[CSS21]<!--{{!CSS21}}--></a>) or a ‘<code
class=property>text-wrap</code>’ of ‘<code
class=css>none</code>’ (see <a href="#CSS3TEXT"
rel=biblioentry>[CSS3TEXT]<!--{{!CSS3TEXT}}--></a>).
</ul>
<h3 id=default-adjustment-calculation><span class=secno>2.3.
</span>Calculation of default adjustment</h3>
<p>The adjustment performed should be based on preferences (of the renderer
or the renderer's user) indicating the desired <dfn
id=minimum-readable-text-size>minimum readable text size</dfn>. Given this
preference, for each containing block of text to be adjusted, there is a
<dfn id=minimum-block-text-size>minimum block text size</dfn>: the
preference for the minimum readable text size, times the width of the
containing block, divided by the width of the device.
<p>The size adjustment involves multiplication of sizes by a ratio
determined by the minimum block text size and the computed value of
‘<code class=property>font-size</code>’. This ratio must be at
least the first divided by the second; however, in order to maintain
differentiations between font sizes, it should often be slightly larger.
<span class=issue>Define this with more detail/precision.</span>
<h2 id=adjustment-control><span class=secno>3. </span>Size adjustment
control: the ‘<a href="#text-size-adjust"><code
class=property>text-size-adjust</code></a>’ property</h2>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=text-size-adjust>text-size-adjust</dfn>
<tr>
<th><a href="#values">Value</a>:
<td>auto | none | <percentage>
<tr>
<th>Initial:
<td>auto
<tr>
<th>Applies to:
<td>all elements
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Percentages:
<td>see below
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>as percentage
<tr>
<th>Canonical order:
<td>N/A
</table>
<dl>
<dt><dfn id=auto>‘<code class=css>auto</code>’</dfn>
<dd>Renderers must use the <a href="#default-adjustment">default size
adjustment</a> when displaying on a small device.
<dt><dfn id=none>‘<code class=css>none</code>’</dfn>
<dd>Renderers must not do size adjustment when displaying on a small
device.
<dt><dfn id=percentage><percentage></dfn>
<dd><span class=issue>Need to define what percentages actually mean. Are
they a minimum or a set value? What exactly are they relative to?</span>
</dl>
<h2 id=conformance><span class=secno>4. </span>Conformance</h2>
<h3 id=conventions><span class=secno>4.1. </span>Document conventions</h3>
<p>Conformance requirements are expressed with a combination of descriptive
assertions and RFC 2119 terminology. The key words “MUST”, “MUST
NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”,
“SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in the
normative parts of this document are to be interpreted as described in RFC
2119. However, for readability, these words do not appear in all uppercase
letters in this specification.
<p>All of the text of this specification is normative except sections
explicitly marked as non-normative, examples, and notes. <a
href="#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=conformance-classes><span class=secno>4.2. </span>Conformance
classes</h3>
<p>Conformance to CSS Mobile Text Size Adjustment Module is defined for
three conformance classes:
<dl>
<dt><dfn id=style-sheet title="style sheet!!as conformance class">style
sheet</dfn>
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#style-sheet">CSS
style sheet</a>.
<dt><dfn id=renderer>renderer</dfn>
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a>
that interprets the semantics of a style sheet and renders documents that
use them.
<dt><dfn id=authoring-tool>authoring tool</dfn>
<dd>A <a href="http://www.w3.org/TR/CSS21/conform.html#user-agent">UA</a>
that writes a style sheet.
</dl>
<p>A style sheet is conformant to CSS Mobile Text Size Adjustment Module if
all of its statements that use syntax defined in this module are valid
according to the generic CSS grammar and the individual grammars of each
feature defined in this module.
<p>A renderer is conformant to CSS Mobile Text Size Adjustment Module if,
in addition to interpreting the style sheet as defined by the appropriate
specifications, it supports all the features defined by CSS Mobile Text
Size Adjustment Module by parsing them correctly and rendering the
document accordingly. However, the inability of a UA to correctly render a
document due to limitations of the device does not make the UA
non-conformant. (For example, a UA is not required to render color on a
monochrome monitor.)
<p>An authoring tool is conformant to CSS Mobile Text Size Adjustment
Module if it writes style sheets that are syntactically correct according
to the generic CSS grammar and the individual grammars of each feature in
this module, and meet all other conformance requirements of style sheets
as described in this module.
<h3 id=partial><span class=secno>4.3. </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>4.4. </span>Experimental
implementations</h3>
<p>To avoid clashes with future CSS features, the CSS2.1 specification
reserves a <a
href="http://www.w3.org/TR/CSS21/syndata.html#vendor-keywords">prefixed
syntax</a> for proprietary and experimental extensions to CSS.
<p>Prior to a specification reaching the Candidate Recommendation stage in
the W3C process, all implementations of a CSS feature are considered
experimental. The CSS Working Group recommends that implementations use a
vendor-prefixed syntax for such features, including those in W3C Working
Drafts. This avoids incompatibilities with future changes in the draft.
<h3 id=testing><span class=secno>4.5. </span>Non-experimental
implementations</h3>
<p>Once a specification reaches the Candidate Recommendation stage,
non-experimental implementations are possible, and implementors should
release an unprefixed implementation of any CR-level feature they can
demonstrate to be correctly implemented according to spec.
<p>To establish and maintain the interoperability of CSS across
implementations, the CSS Working Group requests that non-experimental CSS
renderers submit an implementation report (and, if necessary, the
testcases used for that implementation report) to the W3C before releasing
an unprefixed implementation of any CSS features. Testcases submitted to
W3C are subject to review and correction by the CSS Working Group.
<p>Further information on submitting testcases and implementation reports
can be found from on the CSS Working Group's website at <a
href="http://www.w3.org/Style/CSS/Test/">http://www.w3.org/Style/CSS/Test/</a>.
Questions should be directed to the <a
href="http://lists.w3.org/Archives/Public/public-css-testsuite">public-css-testsuite@w3.org</a>
mailing list.
<h3 id=cr-exit-criteria><span class=secno>4.6. </span>CR exit criteria</h3>
<p> For this specification to be advanced to Proposed Recommendation, there
must be at least two independent, interoperable implementations of each
feature. Each feature may be implemented by a different set of products,
there is no requirement that all features be implemented by a single
product. For the purposes of this criterion, we define the following
terms:
<dl>
<dt>independent
<dd>each implementation must be developed by a different party and cannot
share, reuse, or derive from code used by another qualifying
implementation. Sections of code that have no bearing on the
implementation of this specification are exempt from this requirement.
<dt>interoperable
<dd>passing the respective test case(s) in the official CSS test suite,
or, if the implementation is not a Web browser, an equivalent test. Every
relevant test in the test suite should have an equivalent test created if
such a user agent (UA) is to be used to claim interoperability. In
addition if such a UA is to be used to claim interoperability, then there
must one or more additional UAs which can also pass those equivalent
tests in the same way for the purpose of interoperability. The equivalent
tests must be made publicly available for the purposes of peer review.
<dt>implementation
<dd>a user agent which:
<ol class=inline>
<li>implements the specification.
<li>is available to the general public. The implementation may be a
shipping product or other publicly available version (i.e., beta
version, preview release, or “nightly build”). Non-shipping product
releases must have implemented the feature(s) for a period of at least
one month in order to demonstrate stability.
<li>is not experimental (i.e., a version specifically designed to pass
the test suite and is not intended for normal usage going forward).
</ol>
</dl>
<p>The specification will remain Candidate Recommendation for at least six
months.
<h2 class=no-num id=acknowledgments>Acknowledgments</h2>
<p>The editors would like to thank: .
<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/2011/REC-CSS2-20110607"><cite>Cascading Style
Sheets Level 2 Revision 1 (CSS 2.1) Specification.</cite></a> 7 June
2011. W3C Recommendation. URL: <a
href="http://www.w3.org/TR/2011/REC-CSS2-20110607">http://www.w3.org/TR/2011/REC-CSS2-20110607</a>
</dd>
<!---->
<dt id=CSS3TEXT>[CSS3TEXT]
<dd>Elika J. Etemad; Koji Ishii. <a
href="http://www.w3.org/TR/2012/WD-css3-text-20120119/"><cite>CSS Text
Level 3.</cite></a> 19 January 2012. W3C Working Draft. (Work in
progress.) URL: <a
href="http://www.w3.org/TR/2012/WD-css3-text-20120119/">http://www.w3.org/TR/2012/WD-css3-text-20120119/</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=CSS3COLOR>[CSS3COLOR]
<dd>Tantek Çelik; Chris Lilley; L. David Baron. <a
href="http://www.w3.org/TR/2011/REC-css3-color-20110607"><cite>CSS Color
Module Level 3.</cite></a> 7 June 2011. W3C Recommendation. URL: <a
href="http://www.w3.org/TR/2011/REC-css3-color-20110607">http://www.w3.org/TR/2011/REC-css3-color-20110607</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>4.2.</strong></a>
<li>‘<code class=css>auto</code>’, <a href="#auto"
title="''auto''"><strong>3.</strong></a>
<li>minimum block text size, <a href="#minimum-block-text-size"
title="minimum block text size"><strong>2.3.</strong></a>
<li>minimum readable text size, <a href="#minimum-readable-text-size"
title="minimum readable text size"><strong>2.3.</strong></a>
<li>‘<code class=css>none</code>’, <a href="#none"
title="''none''"><strong>3.</strong></a>
<li><percentage>, <a href="#percentage"
title="<percentage>"><strong>3.</strong></a>
<li>renderer, <a href="#renderer" title=renderer><strong>4.2.</strong></a>
<li>style sheet
<ul>
<li>as conformance class, <a href="#style-sheet"
title="style sheet, as conformance class"><strong>4.2.</strong></a>
</ul>
<li>text-size-adjust, <a href="#text-size-adjust"
title=text-size-adjust><strong>3.</strong></a>
</ul>
<!--end-index-->
<h2 class=no-num id=property-index>Property index</h2>
<!--begin-properties-->
<table class=proptable>
<thead>
<tr>
<th>Property
<th>Values
<th>Initial
<th>Applies to
<th>Inh.
<th>Percentages
<th>Media
<tbody>
<tr>
<th><a class=property href="#text-size-adjust">text-size-adjust</a>
<td>auto | none | <percentage>
<td>auto
<td>all elements
<td>yes
<td>see below
<td>visual
</table>
<!--end-properties-->
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