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<!doctype html>
<html lang="en">
<head>
<meta content="text/html; charset=utf-8" http-equiv="Content-Type">
<title>CSS Inline Layout Module Level 3</title>
<meta content="exploring" name="csswg-work-status">
<meta content="ED" name="w3c-status">
<link href="../default.css" rel="stylesheet" type="text/css">
<link href="../csslogo.ico" rel="shortcut icon" type="image/x-icon">
<style>
body {
background: url("https://www.w3.org/StyleSheets/TR/logo-ED") top left no-repeat white;
background-attachment: fixed;
color: black;
font-family: sans-serif;
margin: 0 auto;
max-width: 50em;
padding: 2em 1em 2em 70px;
}
:link { color: #00C; background: transparent }
:visited { color: #609; background: transparent }
a[href]:active { color: #C00; background: transparent }
a[href]:hover { background: #ffa }
a[href] img { border-style: none }
h1, h2, h3, h4, h5, h6 { text-align: left }
h1, h2, h3 { color: #005A9C; }
h1 { font: 170% sans-serif }
h2 { font: 140% sans-serif }
h3 { font: 120% sans-serif }
h4 { font: bold 100% sans-serif }
h5 { font: italic 100% sans-serif }
h6 { font: small-caps 100% sans-serif }
.hide { display: none }
div.head { margin-bottom: 1em }
div.head h1 { margin-top: 2em; clear: both }
div.head table { margin-left: 2em; margin-top: 2em }
p.copyright { font-size: small }
p.copyright small { font-size: small }
pre { margin-left: 2em }
dt { font-weight: bold }
ul.toc, ol.toc {
list-style: none;
}
</style>
<meta content="Bikeshed 1.0.0" name="generator">
<style media="print" type="text/css">
img#edge { width: 80%; height: 70%;}
dt.label { display: run-in; }
</style>
</head>
<body class="h-entry">
<div class="head">
<p data-fill-with="logo"><a class="logo" href="http://www.w3.org/">
<img alt="W3C" height="48" src="https://www.w3.org/Icons/w3c_home" width="72">
</a>
</p>
<h1 class="p-name no-ref" id="title">CSS Inline Layout Module Level 3</h1>
<h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Editor’s Draft,
<time class="dt-updated" datetime="2015-08-12">12 August 2015</time></span></h2>
<div data-fill-with="spec-metadata">
<dl>
<dt>This version:
<dd><a class="u-url" href="http://dev.w3.org/csswg/css-inline/">http://dev.w3.org/csswg/css-inline/</a>
<dt>Latest version:
<dd><a href="http://www.w3.org/TR/css-inline/">http://www.w3.org/TR/css-inline/</a>
<dt>Previous Versions:
<dd><a href="http://www.w3.org/TR/2002/WD-css3-linebox-20020515/" rel="previous">http://www.w3.org/TR/2002/WD-css3-linebox-20020515/</a>
<dt>Feedback:
<dd><span><a href="mailto:www-style@w3.org?subject=%5Bcss-inline%5D%20YOUR%20TOPIC%20HERE">www-style@w3.org</a> with subject line “<kbd>[css-inline] <var>… message topic …</var></kbd>” (<a href="http://lists.w3.org/Archives/Public/www-style/" rel="discussion">archives</a>)</span>
<dt>Issue Tracking:
<dd><a href="https://github.com/w3c/csswg-drafts/issues/">GitHub</a>
<dd><a href="#issues-index">Inline In Spec</a>
<dt class="editor">Editors:
<dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:dauwhe@gmail.com">Dave Cramer</a> (<span class="p-org org">Hachette Livre</span>)
<dd class="editor p-author h-card vcard"><a class="p-name fn u-url url" href="http://fantasai.inkedblade.net/contact">Elika J. Etemad</a> (<span class="p-org org">Invited Expert</span>)
<dd class="editor p-author h-card vcard"><a class="p-name fn u-email email" href="mailto:szilles@adobe.com">Steve Zilles</a> (<span class="p-org org">Adobe</span>)
<dt>Issues list:
<dd><span><a href="https://www.w3.org/Bugs/Public/buglist.cgi?query_format=advanced&product=CSS&component=Linebox&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED">CSS3 Line Layout issues in Bugzilla</a></span>
</dl>
</div>
<div data-fill-with="warning"></div>
<p class="copyright" data-fill-with="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 2015 <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>). 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>
<hr title="Separator for header">
</div>
<h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
<div class="p-summary" data-fill-with="abstract">
<p>The CSS formatting model provides for a flow of elements and text inside of a container to be wrapped into lines. The formatting of elements and text within a line, its positioning in the inline progression direction, and the breaking of lines are described in <a data-link-type="biblio" href="#biblio-css3text">[CSS3TEXT]</a>. This module describes the positioning in the block progression direction both of elements and text within lines and of the lines themselves. This positioning is often relative to a baseline. It also describes special features for formatting of first lines and drop caps. It extends on the model in <a data-link-type="biblio" href="#biblio-css2">[CSS2]</a>.</p>
<a href="http://www.w3.org/TR/CSS/">CSS</a> is a language for describing the rendering of structured documents
(such as HTML and XML)
on screen, on paper, in speech, etc.</div>
<h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
<div data-fill-with="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>
<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-inline%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-inline” in the subject,
preferably like this:
“[css-inline] <em>…summary of comment…</em>”
</p>
<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>
<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>
<p>
This document is governed by the <a href="http://www.w3.org/2014/Process-20140801/" id="w3c_process_revision">1 August 2014 W3C Process Document</a>.
</p>
<p>
</p></div>
<div data-fill-with="at-risk"></div>
<h2 class="no-num no-toc no-ref heading settled" id="contents"><span class="content">Table of Contents</span></h2>
<div data-fill-with="table-of-contents" role="navigation">
<ul class="toc" role="directory">
<li><a href="#line-height"><span class="secno">1</span> <span class="content">Line Heights and Baseline Alignment</span></a>
<ul class="toc">
<li><a href="#dominant-baseline property"><span class="secno">1.1</span> <span class="content">
Dominant Baselines: the <span class="property">dominant-baseline</span> property</span></a>
<li><a href="#transverse-alignment"><span class="secno">1.2</span> <span class="content">
Transverse Box Alignment: the <span class="property">vertical-align</span> property</span></a>
<ul class="toc">
<li><a href="#alignment-baseline-property"><span class="secno">1.2.1</span> <span class="content">
Alignment Point: <span class="property">alignment-baseline</span> longhand</span></a>
<li><a href="#baseline-shift-property"><span class="secno">1.2.2</span> <span class="content">
Alignment Shift: <span class="property">baseline-shift</span> longhand</span></a>
</ul>
</ul>
<li><a href="#initial-letter-styling"><span class="secno">2</span> <span class="content">
Initial Letters</span></a>
<ul class="toc">
<li><a href="#initial-letter-intro"><span class="secno">2.1</span> <span class="content">
An Introduction to Initial Letters</span></a>
<ul class="toc">
<li><a href="#drop-initial"><span class="secno">2.1.1</span> <span class="content">
Drop Initial</span></a>
<li><a href="#sunk-initial"><span class="secno">2.1.2</span> <span class="content">
Sunken Initial Letters</span></a>
<li><a href="#raise-initial"><span class="secno">2.1.3</span> <span class="content">
Raised Initial Letters</span></a>
</ul>
<li><a href="#selecting-drop-initials"><span class="secno">2.2</span> <span class="content">Selecting Initial Letters</span></a>
<li><a href="#sizing-drop-initials"><span class="secno">2.3</span> <span class="content">
Creating Initial Letters: the <span class="property">initial-letter</span> property</span></a>
<ul class="toc">
<li><a href="#processing-model"><span class="secno">2.3.1</span> <span class="content">Layout Model</span></a>
<li><a href="#initial-letter-box"><span class="secno">2.3.2</span> <span class="content">
Content-box Size, Margins, Borders, and Padding</span></a>
</ul>
<li><a href="#aligning-initial-letter"><span class="secno">2.4</span> <span class="content">
Alignment of Initial Letters: the <span class="property">initial-letter-align</span> property</span></a>
<ul class="toc">
<li><a href="#initial-letter-align-defaults"><span class="secno">2.4.1</span> <span class="content">
UA Default Stylesheet for <span class="property">initial-letter-align</span></span></a>
</ul>
<li><a href="#sizing-initial-letters"><span class="secno">2.5</span> <span class="content">
Sizing Initial Letters</span></a>
<ul class="toc">
<li><a href="#initial-letter-shaping"><span class="secno">2.5.1</span> <span class="content">
Shaping and Glyph Selection</span></a>
</ul>
<li><a href="#initial-letter-exclusions"><span class="secno">2.6</span> <span class="content">
Space Around Initial Letters</span></a>
<li><a href="#initial-letter-position"><span class="secno">2.7</span> <span class="content">
Positioning and Kerning Initial Letters</span></a>
<li><a href="#initial-letter-wrapping"><span class="secno">2.8</span> <span class="content">
Initial Letter Wrapping: the <span class="property">initial-letter-wrap</span> property</span></a>
<li><a href="#initial-letter-indentation"><span class="secno">2.9</span> <span class="content">
Indentation and Multi-line Effects</span></a>
<li><a href="#initial-letter-paragraphs"><span class="secno">2.10</span> <span class="content">
Clearing Initial Letters</span></a>
<ul class="toc">
<li><a href="#raised-sunken-caps"><span class="secno">2.10.1</span> <span class="content">
Raised and sunken caps</span></a>
<li><a href="#short-para-initial-letter"><span class="secno">2.10.2</span> <span class="content">
Short paragraphs with initial letters</span></a>
<li><a href="#initial-letter-floats"><span class="secno">2.10.3</span> <span class="content">
Interaction with floats</span></a>
</ul>
</ul>
<li><a href="#ack"><span class="secno"></span> <span class="content">
Acknowledgments</span></a>
<li><a href="#conformance"><span class="secno"></span> <span class="content">
Conformance</span></a>
<ul class="toc">
<li><a href="#conventions"><span class="secno"></span> <span class="content">
Document conventions</span></a>
<li><a href="#conformance-classes"><span class="secno"></span> <span class="content">
Conformance classes</span></a>
<li><a href="#partial"><span class="secno"></span> <span class="content">
Partial implementations</span></a>
<li><a href="#experimental"><span class="secno"></span> <span class="content">
Experimental implementations</span></a>
<li><a href="#testing"><span class="secno"></span> <span class="content">
Non-experimental implementations</span></a>
</ul>
<li><a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
<ul class="toc">
<li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
<li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
</ul>
<li><a href="#references"><span class="secno"></span> <span class="content">References</span></a>
<ul class="toc">
<li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
<li><a href="#informative"><span class="secno"></span> <span class="content">Informative References</span></a>
</ul>
<li><a href="#property-index"><span class="secno"></span> <span class="content">Property Index</span></a>
<li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
</ul></div>
<main>
<h2 class="heading settled" data-level="1" id="line-height"><span class="secno">1. </span><span class="content">Line Heights and Baseline Alignment</span><a class="self-link" href="#line-height"></a></h2>
<p class="issue" id="issue-1a1ecd92"><a class="self-link" href="#issue-1a1ecd92"></a>This section is being rewritten. Refer to <a href="http://www.w3.org/TR/CSS21/visudet.html#line-height">section 10.8</a> of <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a> for the normative CSS definition or the <a href="http://www.w3.org/TR/2002/WD-css3-linebox-20020515/">2002 Working Draft</a> if you want pretty pictures. (But ignore the old text, half of it’s wrong. We’re not specifying which half, that’s to be determined.)</p>
<h3 class="heading settled" data-level="1.1" id="dominant-baseline property"><span class="secno">1.1. </span><span class="content">
Dominant Baselines: the <a class="property" data-link-type="propdesc" href="#propdef-dominant-baseline">dominant-baseline</a> property</span><a class="self-link" href="#dominant-baseline%20property"></a></h3>
<table class="definition propdef" data-link-for-hint="dominant-baseline">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-dominant-baseline">dominant-baseline<a class="self-link" href="#propdef-dominant-baseline"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod">auto <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> text-bottom <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> alphabetic <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> central <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> mathematical <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> hanging <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> text-top
<tr>
<th>Initial:
<td>normal
<tr>
<th>Applies to:
<td>block containers and inline boxes
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no</table>
<p>This property specifies the <dfn data-dfn-type="dfn" data-noexport="" id="dominant-baseline">dominant baseline<a class="self-link" href="#dominant-baseline"></a></dfn>,
which is the baseline used to align the box’s text and inline-level contents.
Values have the following meanings:</p>
<dl>
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-auto">auto<a class="self-link" href="#valdef-dominant-baseline-auto"></a></dfn>
<dd>
Equivalent to <a class="css" data-link-type="maybe" href="#valdef-dominant-baseline-alphabetic">alphabetic</a> in <i>horizontal writing modes</i>
and in <i>vertical writing modes</i>
when <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-writing-modes-3/#propdef-text-orientation">text-orientation</a> is <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-sideways">sideways</a>, <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-sideways-right">sideways-right</a>, or <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-sideways-left">sideways-left</a>.
equivalent to <a class="css" data-link-type="maybe" href="#valdef-dominant-baseline-central">central</a> in <i>vertical writing modes</i>
when <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-writing-modes-3/#propdef-text-orientation">text-orientation</a> is <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-mixed">mixed</a> or <a class="css" data-link-type="maybe" href="https://drafts.csswg.org/css-writing-modes-3/#valdef-text-orientation-upright">upright</a>.
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-text-bottom">text-bottom<a class="self-link" href="#valdef-dominant-baseline-text-bottom"></a></dfn>
<dd>
Use the bottom of the em box as the baseline.
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-alphabetic">alphabetic<a class="self-link" href="#valdef-dominant-baseline-alphabetic"></a></dfn>
<dd>
Use the alphabetic baseline.
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-central">central<a class="self-link" href="#valdef-dominant-baseline-central"></a></dfn>
<dd>
Use the central baseline
(halfway between the ascent and descent).
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-mathematical">mathematical<a class="self-link" href="#valdef-dominant-baseline-mathematical"></a></dfn>
<dd>
Use the mathematical baseline.
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-hanging">hanging<a class="self-link" href="#valdef-dominant-baseline-hanging"></a></dfn>
<dd>
Use the hanging baseline.
<dt><dfn class="css" data-dfn-for="dominant-baseline" data-dfn-type="value" data-export="" id="valdef-dominant-baseline-text-top">text-top<a class="self-link" href="#valdef-dominant-baseline-text-top"></a></dfn>
<dd>
Use the top of the em box as the baseline.
</dl>
<p>See <a data-link-type="biblio" href="#biblio-css3-writing-modes">[CSS3-WRITING-MODES]</a> for an introduction to dominant baselines.</p>
<p class="issue" id="issue-5c2889ea"><a class="self-link" href="#issue-5c2889ea"></a> Should be text-over and text-under instead of text-top and text-bottom,
but maybe it’s better not to use those terms for consistency with legacy <a class="property" data-link-type="propdesc" href="#propdef-vertical-align">vertical-align</a>.</p>
<h3 class="heading settled" data-level="1.2" id="transverse-alignment"><span class="secno">1.2. </span><span class="content">
Transverse Box Alignment: the <a class="property" data-link-type="propdesc" href="#propdef-vertical-align">vertical-align</a> property</span><a class="self-link" href="#transverse-alignment"></a></h3>
<table class="definition propdef" data-link-for-hint="vertical-align">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-vertical-align">vertical-align<a class="self-link" href="#propdef-vertical-align"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod"><a class="production" data-link-type="propdesc" href="#propdef-baseline-shift"><‘baseline-shift’></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-any">||</a> <a class="production" data-link-type="propdesc" href="#propdef-alignment-baseline"><‘alignment-baseline’></a>
<tr>
<th>Initial:
<td>baseline
<tr>
<th>Applies to:
<td>inline-level boxes
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no</table>
<p>This shorthand property specifies how an inline-level box is aligned within the line.
Values are the same as for its longhand properties, see below.
</p>
<p class="advisement">
Authors should use this property (<a class="property" data-link-type="propdesc" href="#propdef-vertical-align">vertical-align</a>) instead of its longhands.
</p>
<h4 class="heading settled" data-level="1.2.1" id="alignment-baseline-property"><span class="secno">1.2.1. </span><span class="content">
Alignment Point: <a class="property" data-link-type="propdesc" href="#propdef-alignment-baseline">alignment-baseline</a> longhand</span><a class="self-link" href="#alignment-baseline-property"></a></h4>
<table class="definition propdef" data-link-for-hint="alignment-baseline">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-alignment-baseline">alignment-baseline<a class="self-link" href="#propdef-alignment-baseline"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod">baseline <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> text-bottom <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> alphabetic <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> middle <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> central <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> mathematical <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> text-top <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> bottom <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> center <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> top
<tr>
<th>Initial:
<td>baseline
<tr>
<th>Applies to:
<td>inline-level boxes
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no</table>
<p>Specifies what point of an inline-level box is aligned to what point in the parent.
Values are defined below:
</p>
<p>For the following definitions, the margin box is used for atomic inlines,
and the leading box for non-replaced inlines:</p>
<dl>
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-baseline">baseline<a class="self-link" href="#valdef-alignment-baseline-baseline"></a></dfn>
<dd>
Use the <i>dominant baseline</i> choice of the parent.
Match the box’s corresponding baseline to that of its parent.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-text-bottom">text-bottom<a class="self-link" href="#valdef-alignment-baseline-text-bottom"></a></dfn>
<dd>
Match the bottom of the box to the bottom of the parent’s content area.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-alphabetic">alphabetic<a class="self-link" href="#valdef-alignment-baseline-alphabetic"></a></dfn>
<dd>
Match the box’s alphabetic baseline to that of its parent.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-middle">middle<a class="self-link" href="#valdef-alignment-baseline-middle"></a></dfn>
<dd>
Align the vertical midpoint of the box with
the baseline of the parent box plus half the x-height of the parent.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-central">central<a class="self-link" href="#valdef-alignment-baseline-central"></a></dfn>
<dd>
Match the box’s central baseline to the central baseline of its parent.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-mathematical">mathematical<a class="self-link" href="#valdef-alignment-baseline-mathematical"></a></dfn>
<dd>
Match the box’s mathematical baseline to that of its parent.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-text-top">text-top<a class="self-link" href="#valdef-alignment-baseline-text-top"></a></dfn>
<dd>
Match the top of the box to the top of the parent’s content area.
</dl>
<p>For the following definitions, the <i>alignment subtree</i>
is as defined in <a data-link-type="biblio" href="#biblio-css21">[CSS21]</a>.</p>
<dl>
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-top">top<a class="self-link" href="#valdef-alignment-baseline-top"></a></dfn>
<dd>
Align the top of the aligned subtree with the top of the line box.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-center">center<a class="self-link" href="#valdef-alignment-baseline-center"></a></dfn>
<dd>
Align the center of the aligned subtree with the center of the line box.
<dt><dfn class="css" data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-bottom">bottom<a class="self-link" href="#valdef-alignment-baseline-bottom"></a></dfn>
<dd>
Align the bottom of the aligned subtree with the bottom of the line box.
</dl>
<p class="issue" id="issue-b59edfd8"><a class="self-link" href="#issue-b59edfd8"></a> Putting <a class="css" data-link-type="maybe" href="#valdef-alignment-baseline-top">top</a>, <a class="css" data-link-type="maybe" href="#valdef-alignment-baseline-center">center</a>, and <a class="css" data-link-type="maybe" href="#valdef-alignment-baseline-bottom">bottom</a> in here is awkward,
because they’re not really baselines. :/</p>
<p>SVG implementations <em>may</em> support the following aliases
in order to support legacy content:</p>
<pre><dfn data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-before-edge">before-edge<a class="self-link" href="#valdef-alignment-baseline-before-edge"></a></dfn> | <dfn data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-text-before-edge">text-before-edge<a class="self-link" href="#valdef-alignment-baseline-text-before-edge"></a></dfn> = <a data-link-type="maybe" href="#valdef-alignment-baseline-text-top">text-top</a>
<dfn data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-after-edge">after-edge<a class="self-link" href="#valdef-alignment-baseline-after-edge"></a></dfn> | <dfn data-dfn-for="alignment-baseline" data-dfn-type="value" data-export="" id="valdef-alignment-baseline-text-after-edge">text-after-edge<a class="self-link" href="#valdef-alignment-baseline-text-after-edge"></a></dfn> = <a data-link-type="maybe" href="#valdef-alignment-baseline-text-bottom">text-bottom</a>
</pre>
<p>These values are not allowed in the <a class="property" data-link-type="propdesc" href="#propdef-vertical-align">vertical-align</a> shorthand.</p>
<h4 class="heading settled" data-level="1.2.2" id="baseline-shift-property"><span class="secno">1.2.2. </span><span class="content">
Alignment Shift: <a class="property" data-link-type="propdesc" href="#propdef-baseline-shift">baseline-shift</a> longhand</span><a class="self-link" href="#baseline-shift-property"></a></h4>
<table class="definition propdef" data-link-for-hint="baseline-shift">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-baseline-shift">baseline-shift<a class="self-link" href="#propdef-baseline-shift"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value"><length></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value"><percentage></a> <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> sub <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> super
<tr>
<th>Initial:
<td>0
<tr>
<th>Applies to:
<td>inline-level boxes
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>refer to the used value of <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-line-height">line-height</a>
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>absolute length, percentage, or keyword specified
<tr>
<th>Animatable:
<td>no</table>
<p>This property specifies by how much the box is shifted up
from its alignment point.
It does not apply when <a class="property" data-link-type="propdesc" href="#propdef-alignment-baseline">alignment-baseline</a> is <a class="css" data-link-type="maybe" href="#valdef-alignment-baseline-top">top</a> or <a class="css" data-link-type="maybe" href="#valdef-alignment-baseline-bottom">bottom</a>.
</p>
<p class="advisement">
Authors should use the <a class="property" data-link-type="propdesc" href="#propdef-vertical-align">vertical-align</a> shorthand instead of this property.
</p>
<p>Values have the following meanings:</p>
<dl>
<dt><dfn class="css" data-dfn-for="baseline-shift" data-dfn-type="value" data-export="" id="valdef-baseline-shift-length"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#length-value"><length></a><a class="self-link" href="#valdef-baseline-shift-length"></a></dfn>
<dd>Raise (positive value) or lower (negative value) by the specified length.
<dt><dfn class="css" data-dfn-for="baseline-shift" data-dfn-type="value" data-export="" id="valdef-baseline-shift-percentage"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#percentage-value"><percentage></a><a class="self-link" href="#valdef-baseline-shift-percentage"></a></dfn>
<dd>Raise (positive value) or lower (negative value) by the specified percentage of the <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css2/visudet.html#propdef-line-height">line-height</a>.
<dt><dfn class="css" data-dfn-for="baseline-shift" data-dfn-type="value" data-export="" id="valdef-baseline-shift-sub">sub<a class="self-link" href="#valdef-baseline-shift-sub"></a></dfn>
<dd>Lower by the offset appropriate for subscripts of the parent’s box.
(The UA should use the parent’s font data to find this offset whenever possible.)
<dt><dfn class="css" data-dfn-for="baseline-shift" data-dfn-type="value" data-export="" id="valdef-baseline-shift-super">super<a class="self-link" href="#valdef-baseline-shift-super"></a></dfn>
<dd>Raise by the offset appropriate for superscripts of the parent’s box.
(The UA should use the parent’s font data to find this offset whenever possible.)
</dl>
<p>User agents <em>may</em> additionally support the keyword <dfn data-dfn-for="baseline-shift" data-dfn-type="dfn" data-noexport="" id="baseline" type="value">baseline<a class="self-link" href="#baseline"></a></dfn>
as computing to <span class="css">0</span>
if is necessary for them to support legacy SVG content.
Issue: We would prefer to remove this, and are looking for feedback from SVG user agents as to whether it’s necessary.
</p>
<h2 class="heading settled" data-level="2" id="initial-letter-styling"><span class="secno">2. </span><span class="content">
Initial Letters</span><a class="self-link" href="#initial-letter-styling"></a></h2>
<p class="issue" id="issue-f90429eb"><a class="self-link" href="#issue-f90429eb"></a>The editors would appreciate any examples of drop initials in non-western scripts, especially Arabic and Indic scripts.</p>
<h3 class="heading settled" data-level="2.1" id="initial-letter-intro"><span class="secno">2.1. </span><span class="content">
An Introduction to Initial Letters</span><a class="self-link" href="#initial-letter-intro"></a></h3>
<p>Large, decorative letters have been used to start new sections of text since before the invention of printing. In fact, their use predates lowercase letters entirely.</p>
<h4 class="heading settled" data-level="2.1.1" id="drop-initial"><span class="secno">2.1.1. </span><span class="content">
Drop Initial</span><a class="self-link" href="#drop-initial"></a></h4>
<p>A <dfn data-dfn-type="dfn" data-noexport="" id="dropped-initial">dropped initial<a class="self-link" href="#dropped-initial"></a></dfn> (or “drop cap”) is a larger-than-usual letter at the start of a paragraph, with a baseline at least one line lower than the first baseline of the paragraph. The size of the drop initial is usually indicated by how many lines it occupies. Two- and three-line drop initials are very common.</p>
<figure>
<img alt="3-line drop cap with E Acute" src="images/Dropcap-E-acute-3line.png" width="480">
<p class="caption">Three-line drop initial with E acute. Since the cap-height of the drop initial aligns with the cap-height of the main text, the accent extends above the paragraph.</p>
</figure>
<p>The exact size and position of a <a data-link-type="dfn" href="#dropped-initial">dropped initial</a> depends on the alignment of its glyph. Reference points on the drop cap must align precisely with reference points in the text. In Western scripts, the top reference points are the cap height of the initial letter and of the first line of text. The bottom reference points are the alphabetic baseline of the initial letter and the baseline of the Nth line of text. <a href="#f2">Figure 2</a> shows a simple two-line drop cap, with the relevant reference lines marked.</p>
<figure id="f2">
<img alt="drop cap showing alignment" src="images/Dropcap-lines.png" width="600">
<p class="caption">Two-line drop cap showing baselines (green lines), cap-height (red line), and ascender (cyan line).</p>
</figure>
<p>The alignment constraints for drop initials depend on the writing system. In ideographic scripts, the initial letter extends from the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#block_start">block-start</a> edge of the first line to the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#block_end">block-end</a> edge of the Nth line.</p>
<figure>
<img alt="Japanese Vertical Initial" src="images/Initial-2line-JapaneseVertical六.png" width="480">
<p class="caption">Two-line drop initial in vertical writing mode</p>
</figure>
<p>In some Indic scripts, the top alignment point
is the hanging baseline,
and the bottom alignment point is the text-after-edge.</p>
<figure>
<img alt="Devangari initial letter" src="images/Devangari-Initial.png" width="480">
<p class="caption">Devangari <a data-link-type="dfn" href="#initial-letter">initial letter</a> aligned with hanging baseline. Alignment points shown in red.</p>
</figure>
<h4 class="heading settled" data-level="2.1.2" id="sunk-initial"><span class="secno">2.1.2. </span><span class="content">
Sunken Initial Letters</span><a class="self-link" href="#sunk-initial"></a></h4>
<p>Some styles of drop initials do not align with the first line of text. A <dfn data-dfn-type="dfn" data-noexport="" id="sunken-initial">sunken initial<a class="self-link" href="#sunken-initial"></a></dfn> (or “sunken cap”) both sinks below the first baseline, and extends above the first line of text.</p>
<figure>
<img alt="sunken drop initial" src="images/SunkenCapA.png" width="480">
<p class="caption">Sunken cap. The letter drops two lines, but is the size of a three-line initial letter.</p>
</figure>
<h4 class="heading settled" data-level="2.1.3" id="raise-initial"><span class="secno">2.1.3. </span><span class="content">
Raised Initial Letters</span><a class="self-link" href="#raise-initial"></a></h4>
<p>A <dfn data-dfn-type="dfn" data-noexport="" id="raised-initial">raised initial<a class="self-link" href="#raised-initial"></a></dfn> (often called a “raised cap” or “stick-up cap”) “sinks” to the first text baseline. Unlike simply increasing the font size, which affects the line spacing below it to make room for potential descenders, it does not sink below that.</p>
<figure>
<img alt="raised cap" src="images/RaisedCap.png" width="480">
<p class="caption">Raised cap. The initial letter is the size of a 3-line initial, but does not drop.</p>
</figure>
<h3 class="heading settled" data-level="2.2" id="selecting-drop-initials"><span class="secno">2.2. </span><span class="content">Selecting Initial Letters</span><a class="self-link" href="#selecting-drop-initials"></a></h3>
<p>Initial letters are typically a single letter, which can be selected by the <code>::first-letter</code> pseudo-element, as defined in <a data-link-type="biblio" href="#biblio-select">[SELECT]</a>.</p>
<p>Authors who need more control over which characters are included in an initial letter, or who want to apply initial-letter formatting to replaced elements or multiple words can also apply the <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> property to the first inline-level child of a block container.
</p>
<div class="example" id="example-9394ec8b"><a class="self-link" href="#example-9394ec8b"></a>
<pre><p>This paragraph has a dropped “T”.
<p><img alt="H" src="illuminated-h.svg">ere we have an illuminated “H”.
<p><span>Words may also</span> be given initial letter styling at the beginning of a paragraph.
</pre>
<pre>::first-letter, /* style first paragraph’s T */
img, /* style illuminated H */
span /* drop Words may also */
{ initial-letter: 2; }
</pre>
</div>
<h3 class="heading settled" data-level="2.3" id="sizing-drop-initials"><span class="secno">2.3. </span><span class="content">
Creating Initial Letters: the <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> property</span><a class="self-link" href="#sizing-drop-initials"></a></h3>
<table class="definition propdef" data-link-for-hint="<dfn id="propdef-initial-letter">initial-letter</dfn>">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-initial-letter">initial-letter<a class="self-link" href="#propdef-initial-letter"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod">normal <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> [<a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#number-value"><number></a> <a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value"><integer></a><a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#mult-opt">?</a>]
<tr>
<th>Initial:
<td>normal
<tr>
<th>Applies to:
<td><code>::first-letter</code> pseudo-elements and inline-level first child of a block container
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>as specified
<tr>
<th>Animatable:
<td>no</table>
<p>This property specifies styling for dropped, raised, and sunken initial letters. It takes the following values:</p>
<dl>
<dt><dfn class="css" data-dfn-for="initial-letter" data-dfn-type="value" data-export="" id="valdef-initial-letter-normal">normal<a class="self-link" href="#valdef-initial-letter-normal"></a></dfn>
<dd>No special initial-letter effect. Text behaves as normal.
<dt><dfn class="css" data-dfn-for="initial-letter" data-dfn-type="value" data-export="" id="valdef-initial-letter-number"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#number-value"><number></a><a class="self-link" href="#valdef-initial-letter-number"></a></dfn>
<dd>This first argument defines the size of the initial letter, in terms of how many lines it occupies. Negative values are not allowed.
<dt><dfn class="css" data-dfn-for="initial-letter" data-dfn-type="value" data-export="" id="valdef-initial-letter-integer"><a class="production css" data-link-type="type" href="https://drafts.csswg.org/css-values-3/#integer-value"><integer></a><a class="self-link" href="#valdef-initial-letter-integer"></a></dfn>
<dd>This optional second argument argument defines the number of lines the initial letter should sink. Values must be greater than zero. If omitted, it duplicates the first argument, floored to the nearest positive whole number.
</dl>
<p>An <dfn data-dfn-type="dfn" data-lt="initial letter | initial letter box" data-noexport="" id="initial-letter">initial letter<a class="self-link" href="#initial-letter"></a></dfn> is
a box to which <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> applies and is not <a class="css" data-link-type="maybe" href="#valdef-initial-letter-normal">normal</a>:
this triggers the special layout considerations described below.</p>
<div class="example" id="example-f3165b99"><a class="self-link" href="#example-f3165b99"></a>
Here are some examples of <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> usage:
<dl>
<dt><a class="css" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter: 3</a>
<dt>(<a class="css" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter: 3 3</a>)
<dd>Represents a <a data-link-type="dfn" href="#dropped-initial">dropped initial</a> 3 lines high, 3 lines deep.
<p><img alt="3 lines high, 3 lines deep" src="images/InitialLetter33.png" width="360"></p>
<dt><a class="css" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter: 3 2</a>
<dd>Represents a <a data-link-type="dfn" href="#sunken-initial">sunken initial</a> 3 lines high, 2 lines deep.
<p><img alt="3 lines high, 2 lines deep" src="images/InitialLetter32.png" width="360"></p>
<dt><a class="css" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter: 3 1</a>
<dd>Represents a <a data-link-type="dfn" href="#raised-initial">raised initial</a> 3 lines high, 1 line deep.
<p><img alt="3 lines high, 1 line deep" src="images/InitialLetter31.png" width="360"></p>
</dl>
</div>
<div class="example" id="example-3c97a721"><a class="self-link" href="#example-3c97a721"></a>
The following code will create a 2-line dropped initial letter at the beginning of each paragraph:
<pre>p::first-letter { initial-letter: 2; }</pre>
</div>
<p class="issue" id="issue-664624cd"><a class="self-link" href="#issue-664624cd"></a> Define interaction with Ruby. Easiest is to make it not apply to/within ruby.</p>
<p>The <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> property does not apply to boxes that are not positioned at the start of the line due to bidi reordering.</p>
<h4 class="heading settled" data-level="2.3.1" id="processing-model"><span class="secno">2.3.1. </span><span class="content">Layout Model</span><a class="self-link" href="#processing-model"></a></h4>
<p>An <a data-link-type="dfn" href="#initial-letter">initial letter</a> is laid out following the steps outlined below:</p>
<ol>
<li>Find the used font size based on its <a class="property" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter</a> size, <a class="property" data-link-type="propdesc" href="#propdef-initial-letter-align">initial-letter-align</a> alignment points, and font metrics.
Note that no layout is required in this step.
The font size used for sizing the <a data-link-type="dfn" href="#initial-letter">initial letter</a> contents <em>does not</em> affect its computed <a class="property" data-link-type="propdesc" href="https://drafts.csswg.org/css-fonts-3/#propdef-font-size">font-size</a> property
(and therefore has no effect on the computation of <span class="css">em</span> length values, etc.).
<li>Size the <a data-link-type="dfn" href="#initial-letter">initial letter</a>’s content box.
The content box of a non-atomic inline initial letter
is the smallest rectangle required to include the entirety of its glyphs
as well as the margin boxes of any atomic inlines it contains.
<li>The initial letter’s margin box is placed at the edge of the line.
If it has no padding or borders, it is negatively offset by the distance
from the start edge of its content box to the point in the content that
would have been placed at the start edge of the containing block if it had <a class="css" data-link-type="propdesc" href="#propdef-initial-letter">initial-letter: none</a>.
<li>Exclude content within the inline letter’s margin box
according to <a class="property" data-link-type="propdesc" href="#propdef-initial-letter-wrap">initial-letter-wrap</a>.
</ol>
<h4 class="heading settled" data-level="2.3.2" id="initial-letter-box"><span class="secno">2.3.2. </span><span class="content">
Content-box Size, Margins, Borders, and Padding</span><a class="self-link" href="#initial-letter-box"></a></h4>
<p>Initial letters can be styled with margins, padding, and borders just like any other box.
Unless <a class="property" data-link-type="propdesc" href="#propdef-initial-letter-align">initial-letter-align</a> is <a class="css" data-link-type="maybe" href="#valdef-initial-letter-align-border-box">border-box</a>,
its vertical alignment and sizing are not affected;
however the effective exclusion area is (and corresponds to the margin area).</p>
<p>When padding and borders are zero, the initial letter may be kerned; see below.</p>
<h3 class="heading settled" data-level="2.4" id="aligning-initial-letter"><span class="secno">2.4. </span><span class="content">
Alignment of Initial Letters: the <a class="property" data-link-type="propdesc" href="#propdef-initial-letter-align">initial-letter-align</a> property</span><a class="self-link" href="#aligning-initial-letter"></a></h3>
<p>As mentioned earlier, the alignment of initial letters depends on the script used. The <a class="property" data-link-type="propdesc" href="#propdef-initial-letter-align">initial-letter-align</a> property can be used to specify the proper alignment.</p>
<table class="definition propdef" data-link-for-hint="<dfn id="propdef-initial-letter-align">initial-letter-align</dfn>">
<tbody>
<tr>
<th>Name:
<td><dfn class="css" data-dfn-type="property" data-export="" id="propdef-initial-letter-align">initial-letter-align<a class="self-link" href="#propdef-initial-letter-align"></a></dfn>
<tr class="value">
<th>Value:
<td class="prod">border-box<a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#mult-opt">?</a> [ alphabetic <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> ideographic <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> hebrew ] <a data-link-type="grammar" href="https://drafts.csswg.org/css-values-3/#comb-one">|</a> border-box
<tr>
<th>Initial:
<td>alphabetic
<tr>
<th>Applies to:
<td><code>::first-letter</code> pseudo elements and inline level first child of a block container
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed value:
<td>specified value
<tr>
<th>Animatable:
<td>no</table>
<p>This property specifies the alignment points used to size and position an <a data-link-type="dfn" href="#initial-letter">initial letter</a>.
Two sets of alignment points are necessary:
the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#over">over</a> and <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#under">under</a> alignment points of the <a data-link-type="dfn" href="#initial-letter">initial letter</a>
are matched to corresponding <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#over">over</a> and <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#under">under</a> points of the surrounding text.</p>
<p>Values have the following meanings:</p>
<dl>
<dt><dfn class="css" data-dfn-for="initial-letter-align" data-dfn-type="value" data-export="" id="valdef-initial-letter-align-alphabetic">alphabetic<a class="self-link" href="#valdef-initial-letter-align-alphabetic"></a></dfn>
<dd>Use the alphabetic and cap-height baselines of the surrounding text
to align the <a data-link-type="dfn" href="#initial-letter">initial letter</a>.
<dt><dfn class="css" data-dfn-for="initial-letter-align" data-dfn-type="value" data-export="" id="valdef-initial-letter-align-ideographic">ideographic<a class="self-link" href="#valdef-initial-letter-align-ideographic"></a></dfn>
<dd>Use the ideographic character face bottom and top edge baselines of the surrounding text
to align the <a data-link-type="dfn" href="#initial-letter">initial letter</a>.
<dt><dfn class="css" data-dfn-for="initial-letter-align" data-dfn-type="value" data-export="" id="valdef-initial-letter-align-hebrew">hebrew<a class="self-link" href="#valdef-initial-letter-align-hebrew"></a></dfn>
<dd>Use the alphabetic and (as yet theoretical) hebrew hanging baseline of the surrounding text
to align the <a data-link-type="dfn" href="#initial-letter">initial letter</a>.
<dt><dfn class="css" data-dfn-for="initial-letter-align" data-dfn-type="value" data-export="" id="valdef-initial-letter-align-border-box">border-box<a class="self-link" href="#valdef-initial-letter-align-border-box"></a></dfn>
<dd>Uses the <a data-link-type="dfn" href="#initial-letter">initial letter box</a>’s <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#line_over">line-over</a> and <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#line_under">line-under</a> border edges
as the <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#over">over</a> and <a data-link-type="dfn" href="https://drafts.csswg.org/css-writing-modes-3/#under">under</a> alignment points, respectively.
</dl>
<div class="example" id="example-0cc7f40b"><a class="self-link" href="#example-0cc7f40b"></a>
The vertical writing mode example from <a href="#f2">Figure 2</a> could be coded as: