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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html><head>
<title>CSS Lists and Counters Module Level 3</title>
<meta charset=utf-8>
<link rel="stylesheet" type="text/css" href="http://dev.w3.org/csswg/default.css">
<style type="text/css">
td, th { padding: 0 0.5em; }
.numbering td, .numbering th { vertical-align: top; }
.mapping th { text-align: right; }
.mapping td { text-align: center; }
.roman-example { padding: 0.75em; background: white; color: black; margin: 0.25em 0; display: block; }
.hebrew { display: block; }
.hebrew-example thead { display: none; }
.hebrew-example tbody { display: table; float: left; margin: 1em 2em 0.5em; }
.hebrew-example tr > :first-child { text-align: right; }
.hebrew-example tr > :last-child { text-align: left; }
.hebrew-example + * { clear: both; }
</style>
<link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/W3C-ED">
</head><body>
<div class="head">
<!--logo-->
<h1>CSS Lists and Counters Module Level 3</h1>
<h2 class="no-num no-toc">[LONGSTATUS] [DATE]</h2>
<dl>
<dt>This version:
<dd><!-- <a href="http://www.w3.org/TR/[YEAR]/WD-[SHORTNAME]-[CDATE]">http://www.w3.org/TR/[YEAR]/WD-[SHORTNAME]-[CDATE]</a></dd> -->
<a href="http://dev.w3.org/csswg/css3-lists">http://dev.w3.org/csswg/css3-lists</a></dd>
<dt>Latest Working Draft:
<dd><a href="http://www.w3.org/TR/css3-lists">[LATEST]</a></dd>
<dt>Previous versions:</dt>
<dd><a href="http://www.w3.org/TR/2002/WD-css3-lists-20021107">http://www.w3.org/TR/2002/WD-css3-lists-20021107</a></dd>
<dt>Editor:</dt>
<dd><a href="http://www.xanthir.com/contact">Tab Atkins Jr.</a></dd>
<dt>Previous Editors:</dt> <!-- in the order tantek requested -->
<dd>Ian Hickson, <a href="mailto:ian@hixie.ch">ian@hixie.ch</a></dd>
<dd><span lang="tr">Tantek Çelı̇k</span>, Microsoft Corporation,
<a href="mailto:tantekc@microsoft.com">tantekc@microsoft.com</a></dd>
<dt>Contributors:</dt> <!-- in order of volume of input -->
<dd>Simon Montagu, AOL-TW/Netscape, <a href="mailto:smontagu@netscape.com">smontagu@netscape.com</a></dd>
<dd>Daniel Yacob, <a href="mailto:yacob@geez.org">yacob@geez.org</a></dd>
<dd>Christopher Hoess, <a href="mailto:choess@stwing.upenn.edu">choess@stwing.upenn.edu</a></dd>
<dd>Daniel Glazman, AOL-TW/Netscape, <a href="mailto:glazman@netscape.com">glazman@netscape.com</a></dd>
</dl>
<!--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 draft contains the features of CSS level 3 relating to
list styling. It includes and extends the functionality of
CSS level 2 [[!CSS21]], which builds on CSS level 1
[[CSS1]]. The main extensions compared to level 2 are
<span class="issue">summarize here</span>.
<h2 class="no-num no-toc" id="status">
Status of this document</h2>
<!--status-->
<h2 class="no-num no-toc" id="contents">
Table of contents</h2>
<!--toc-->
<hr>
<!-- ====================================================================== -->
<h2>
Introduction</h2>
<p>The list model in this module differs in some important ways from the list model in CSS2,
specifically in its handling of markers. Implementation experience suggested the CSS2 model
overloaded the ::before and ::after pseudo-elements with too much behavior, while at the same time
introducing new properties when existing properties were sufficient.</p>
<p>Most block-level elements in CSS generate one principal block box. In this module, we discuss two
CSS mechanisms that cause an element to have an associated marker: one method associates one
principal block box (for the element's content) with a separate marker box (for decoration such as a
bullet, image, or number), and the other inserts a marker box into the principal box. Unlike :before
and :after content, the marker box cannot affect the position of the principal box, whatever the
positioning scheme.</p>
<div class="html-example">
<p>For instance, the following example illustrates how markers may be used to add parentheses around
each numbered list item. This HTML application and style sheet:</p>
<pre>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<HTML>
<HEAD>
<TITLE>Creating a list with markers</TITLE>
<STYLE type="text/css">
LI::marker { content: "(" counter(list-item, lower-roman) ")"; }
LI { display: list-item; }
</STYLE>
</HEAD>
<BODY>
<OL>
<LI> This is the first item. </LI>
<LI> This is the second item. </LI>
<LI> This is the third item. </LI>
</OL>
</BODY>
</HTML>
</pre>
<p>should produce something like this: </p>
<pre>
(i) This is the first item.
(ii) This is the second item.
(iii) This is the third item.
</pre>
</div>
<p>With descendant selectors and child selectors, it's possible to specify different marker types
depending on the depth of embedded lists.</p>
<p class="issue">A future release of this module will probably include ways to render tree
lists.</p>
<!-- ====================================================================== -->
<h2>
Declaring a List Item</h2>
<p>To declare a list item, the 'display'
property should be set to ''list-item''. This, in addition to generating
a ''::marker'' pseudo-element and enabling the
properties described below for that element, causes that element to
increment the list item counter ''list-item''.
(This does not affect the specified or computed values of the counter
properties.)</p>
<p>The ''list-item'' counter is a real counter,
and can be directly affected using the 'counter-increment' and ''counter-reset''
properties. It can also be used in the ''counter()'' and ''counters()'' functions.</p>
<p class="issue">The CSS3 box module may define other 'display' values which generate a list
marker. These should also affect the ''list-item'' counter.</p>
<p>Note that this new model makes the ''marker''
display type redundant. That display type is therefore obsolete in the
CSS3 Lists model.</p>
<!-- ====================================================================== -->
<h2 id=list-style-type-property>
List Content: The 'list-style-type' property</h2>
<table class="propdef">
<tr>
<th>Name:
<td><dfn>list-style-type</dfn>
<tr>
<th>Value:
<td><b><string></b> | <b><counter-style></b> | none
<tr>
<th>Initial:
<td>disc
<tr>
<th>Applies To:
<td>all elements with ''display: list-item''
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed Value:
<td>specified value
</table>
<p>This property specifies the default contents of the list item
marker if 'list-style-image' has the
value 'none' or if the image pointed to by the URI cannot be
displayed. The value 'none' specifies no marker, and a string value uses the
given string; otherwise, the value specifies a <b><counter-style></b> which
is used to format the value of the ''list-item'' counter.</p>
<dl>
<dt><dfn><string></dfn></dt>
<dd>The ''::marker'' pseudoelement must use the provided string as its default
contents.</dd>
<dt><dfn>none</dfn></dt>
<dd>The ''::marker'' pseudoelement must have no default contents. This will
suppress the creation of a marker unless the ''::marker'' has its contents
specified directly through the 'content' property.</dd>
<dt><dfn><counter-style></dfn></dt>
<dd>
<p>The ''::marker'' pseudoelement's default contents must be the value of
the ''list-item'' counter, formatted according to the given counter style.
Algorithms for formatting a value according to a counter style are given
later in this spec.</p>
<p>The <b>UA style sheet</b> given later in this spec provides a large list
of counter style definitions, and authors or users may define their own
counter styles as well.</p>
</dd>
</dl>
<!-- ====================================================================== -->
<h2 id=predefined-counters>
Predefined Counter Styles</h2>
<p>While authors may define their own counter styles using the ''@counter-style''
rule defined in this spec, there are many counter styles that CSS already defined
in previous levels, and many more that can be usefully predefined. Appendix A
contains a required UA stylesheet which defines a large number of counter styles
using the ''@counter-style'' rule. A few styles require special handling beyond
what can be expressed in a stylesheet, though. Those counter styles are described
in this section.
<h3 id=decimal-counters>
The ''decimal'' counter style</h3>
<p>The ''decimal'' counter style is the default fallback counter style for the
''@counter-style'' rule, and is also used in extraordinary situations like fallback
loop. As such, it has to be well-defined at all times, so that a counter can
always be formatted regardless of the validity of the defined counter styles.</p>
<p>UAs must not allow the definition of the ''decimal'' counter style given in
Appendix A to be overridden.</p>
<h3 id=glyph-counters>
Glyphs</h3>
<p>CSS 2.1 defined three single-glyph counter styles (''circle'', ''disc'', and
''square''), but didn't define precisely how to render them, instead opting to
describe generally how they should look and leaving it up to the UA to decide how
to render the markers.</p>
<p>Appendix A gives normative definitions for these styles, but UAs may instead
default to rendering these styles using a browser-generated image matching the
description below. If the styles are overridden, the new style must be honored;
this relaxation of the rendering requirements applies only to the default value
of each counter style.</p>
<p>If the UA chooses to use an image for the default rendering of these counter
styles, the image must be scalable and designed to attractively fill a box 1em
wide and 1em tall.</p>
<dl>
<dt>circle</dt>
<dd>A hollow circle, similar to ◦ U+25E6 WHITE BULLET.</dd>
<dt>disc</dt>
<dd>A filled circle, similar to • U+2022 BULLET.</dd>
<dt>square</dt>
<dd>A filled square, similar to ■ U+25A0 BLACK SQUARE.</dd>
</dl>
<h3 id=complex-counters>
Complex counter styles</h3>
<p>Some real-life counter styles are unfortunately too complex to be accurately
described using the ''@counter-style'' rule. The following styles must be supported
as default counter styles as if they were defined by theoretical
''@counter-style'' rules placed at the end of the UA stylesheet defined in Appendix
A, using the given name as the counter style name and the given algorithm to format
counter values. They must be overrideable like any other predefined counter style.</p>
<dl>
<dt>hebrew</dt>
<dd>
<p>This is a simple additive system defined for the range 1 to 999999.
The digits are split into two groups of three. Within each group,
appropriate digits are picked from the following list (at most one per
column) and written in descending order by value (hundreds first). If
there is more than one group, the first group is followed by U+05F3 HEBREW
PUNCTUATION GERESH.</p>
<table>
<caption>Hebrew numbering system</caption>
<thead>
<tr>
<th colspan="3">Hundreds
<th colspan="3">Tens
<th colspan="3">Units
<tr>
<th>Values
<th colspan="2">Codepoints
<th>Values
<th colspan="2">Codepoints
<th>Values
<th colspan="2">Codepoints
<tbody>
<tr>
<td>100
<td>ק
<td>U+05E7
<td>10
<td>י
<td>U+05D9
<td>1
<td>א
<td>U+05D0
<tr>
<td>200
<td>ר
<td>U+05E8
<td>20
<td>כ
<td>U+05DB
<td>2
<td>ב
<td>U+05D1
<tr>
<td>300
<td>ש
<td>U+05E9
<td>30
<td>ל
<td>U+05DC
<td>3
<td>ג
<td>U+05D2
<tr>
<td>400
<td>ת
<td>U+05EA
<td>40
<td>מ
<td>U+05DE
<td>4
<td>ד
<td>U+05D3
<tr>
<td>500
<td>תק
<td>U+05EA U+05E7
<td>50
<td>נ
<td>U+05E0
<td>5
<td>ה
<td>U+05D4
<tr>
<td>600
<td>תר
<td>U+05EA U+05E8
<td>60
<td>ס
<td>U+05E1
<td>6
<td>ו
<td>U+05D5
<tr>
<td>700
<td>תש
<td>U+05EA U+05E9
<td>70
<td>ע
<td>U+05E2
<td>7
<td>ז
<td>U+05D6
<tr>
<td>800
<td>תת
<td>U+05EA U+05EA
<td>80
<td>פ
<td>U+05E4
<td>8
<td>ח
<td>U+05D7
<tr>
<td>900
<td>תתק
<td>U+05EA U+05EA U+05E7
<td>90
<td>צ
<td>U+05E6
<td>9
<td>ט
<td>U+05D8
</table>
<p>If the last two digits of a group (when represented in decimal) are 15
or 16, they should be expressed not as יה U+05D9 U+05D4
(10+5) and יו U+05D9 U+05D5 (10+6), but as
טו U+05D8 U+05D5 (9+6) and טז U+05D8 U+05D6
(9+7). This is done to avoid a close resemblance to the Tetragrammaton
(four-letter name of God) יהוה U+05D9 U+05D4
U+05D5 U+05D4. Although this convention is originally derived from
religious practice, it is universally used even in completely secular
contexts.</p>
<p>The numerical value of each letter is fixed and not determined by
position, so reordering a number group will not change its value. This
may be done when a number spells out a word with negative connotations.
For instance, 298, רצח U+05E8 U+05E6 U+05D7
(200+90+8), is the Hebrew for "murder", so it is sometimes written as
רחצ U+05E8 U+05D7 U+05E6 (200+8+90). Words are
sometimes similarly rearranged when a reordered form has especially
positive connotations, for example 18, יח U+05D9 U+05D7
(10+8) is often written as חי U+05D7 U+05D9 (8+10), the
Hebrew for "alive". Unlike the exception for 15 and 16, using the
regular form in these cases is not considered an error.</p>
<p>The suffix for the hebrew numbering system is a dot (. U+002E
FULL STOP).</p>
<p>Numbers outside the range of the Hebrew system are rendered using the
''decimal'' counter style.</p>
<div class="example">
<p>This table shows the decimal number in the first cell, and the
equivalent hebrew number in the second.</p>
<table class="hebrew-example">
<thead>
<tr>
<th>Decimal
<th>Hebrew
<tbody>
<tr>
<td>-3
<td>-3
<tr>
<td>-2
<td>-2
<tr>
<td>-1
<td>-1
<tr>
<td>0
<td>0
<tr>
<td>1
<td>א
<tr>
<td>2
<td>ב
<tr>
<td>3
<td>ג
<tr>
<td>4
<td>ד
<tr>
<td>5
<td>ה
<tbody>
<tr>
<td>97
<td>צז
<tr>
<td>98
<td>צח
<tr>
<td>99
<td>צט
<tr>
<td>100
<td>ק
<tr>
<td>101
<td>קא
<tr>
<td>944
<td>תתקמד
<tr>
<td>945
<td>תתקמה
<tr>
<td>946
<td>תתקמו
<tr>
<td>999
<td>תתקצט
<tbody>
<tr>
<td>1000
<td>א׳
<tr>
<td>1001
<td>א׳א
<tr>
<td>1998
<td>א׳תתקצח
<tr>
<td>1999
<td>א׳תתקצט
<tr>
<td>2000
<td>ב׳
<tr>
<td>2001
<td>ב׳א
<tr>
<td>2003
<td>ב׳ג
<tr>
<td>2748
<td>ב׳תשמח
<tr>
<td>2750
<td>ב׳תשנ
</table>
<p>This example (like all other examples) is non-normative. If one of
the numbers above is inconsistent with the rules described above, then
the example should be disregarded.</p>
</div>
</dd>
<dt>ethiopic-numeric</dt>
<dd>
<p>The Ethiopian numbering system is defined for all positive non-zero numbers.
The following algorithm converts decimal digits to ethiopic numbers.</p>
<ol>
<li>Split the number into groups of two digits, starting with the least
significant decimal digit.</li>
<li>Index each group sequentially, starting from the least significant
as group number zero.</li>
<li>If the group has an odd index (as given in the previous step) and
has the value 1, or if the group is the most significant one and has
the value 1, or if the group has the value zero, then remove the digit
(but leave the group, so it still has a separator appended below).</li>
<li>For each remaining digit, substitute the relevant ethiopic character
from the list below.
<table>
<caption>Ethiopic numbering system</caption>
<thead>
<tr>
<th colspan="3">Tens
<th colspan="3">Units
<tr>
<th>Values
<th colspan="2">Codepoints
<th>Values
<th colspan="2">Codepoints
<tbody>
<tr>
<td>10
<td>፲
<td>U+1372
<td>1
<td>፩
<td>U+1369
<tr>
<td>20
<td>፳
<td>U+1373
<td>2
<td>፪
<td>U+136A
<tr>
<td>30
<td>፴
<td>U+1374
<td>3
<td>፫
<td>U+136B
<tr>
<td>40
<td>፵
<td>U+1375
<td>4
<td>፬
<td>U+136C
<tr>
<td>50
<td>፶
<td>U+1376
<td>5
<td>፭
<td>U+136D
<tr>
<td>60
<td>፷
<td>U+1377
<td>6
<td>፮
<td>U+136E
<tr>
<td>70
<td>፸
<td>U+1378
<td>7
<td>፯
<td>U+136F
<tr>
<td>80
<td>፹
<td>U+1379
<td>8
<td>፰
<td>U+1370
<tr>
<td>90
<td>፺
<td>U+137A
<td>9
<td>፱
<td>U+1371
</table>
</li>
<li>For each group with an odd index (as given in the second step),
append ፻ U+137B.</li>
<li>For each group with an even index (as given in the second step),
except the group with number 0, append ፼ U+137C.</li>
<li>Concatenate the groups into one string.</li>
</ol>
<p>This system is defined for all numbers greater than zero. For zero and
negative numbers, the decimal system is used instead.</p>
<p>The suffix for the ethiopic-numeric numbering systems is a dot
(. U+002E FULL STOP). <span class="issue">Is there a better suffix
to use? <strong>The alphabetic ethiopic systems use a different
suffix.</strong></span></p>
<div class="example">
<p>The decimal number 100, in ethiopic, is ፻ U+137B <!-- odd --></p>
<p> The decimal number 78010092, in ethiopic, is
፸፰፻፩፼፻፺፪ U+1378
U+1370 U+137B <!-- 70 8 odd --> U+1369 U+137C <!-- 1 even --> U+137B
<!-- odd --> U+137A U+136A. <!-- 90 2 --></p>
<p> The decimal number 780000001092, in ethiopic, is
፸፰፻፩፼፻፼፻፺፪
U+1378 U+1370 U+137B <!-- 70 8 odd --> U+1369 U+137C <!-- 1 even -->
U+137B <!-- odd --> U+137C <!-- even --> U+137B <!-- odd --> U+137A
U+136A. <!-- 90 2 --></p>
</div>
</dd>
</dl>
<!-- ====================================================================== -->
<h2 id=list-style-image-property>
List Content: The 'list-style-image' property</h2>
<table class="propdef">
<tr>
<th>Name:
<td><dfn>list-style-image</dfn>
<tr>
<th>Value:
<td><image> | none
<tr>
<th>Initial
<td>none
<tr>
<th>Applies To:
<td>all elements with ''display: list-item''
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed Value:
<td>specified value
</table>
<p>This property sets the image that will be used as the list item marker. When
the <b><image></b> resolves to a valid image, it is used as the default contents
of ''::marker'' instead of the value specified by 'list-style-type'.</p>
<p>If the value ''none'' is provided, or the <b><image></b> doesn't resolve
to a valid image, then the default contents are given by 'list-style-type' instead.</p>
<div class="example">
<p>The following example sets the marker at the beginning of each list item to
be the image "ellipse.png".</p>
<pre>LI { list-style-image: url("http://www.example.com/ellipse.png") }</pre>
</div>
<!-- ====================================================================== -->
<h2 id=content-property>
List Content: Generating the computed value of the 'content' property</h2>
<p>If a ''::marker'' pseudo-element has its 'content' property set to ''normal'', the
following algorithm should be used to generate the computed value of the property.</p>
<ol>
<li>If the computed value of 'list-style-image' is not ''none'', and if the
image is valid, then the computed value of the 'content' property is the value
of the 'list-style-image' property.</li>
<li>Otherwise, if the computed value of 'list-style-type' is a string, then
the computed value of the 'content' property is that string.</li>
<li>Otherwise, if the computed value of 'list-style-type' is not ''none'', then
the computed value of the 'content' property is ''counter(list-item, <b><counter-style></b>)'',
where <b><counter-style></b> is the computed value of the 'list-style-type'
property, followed by a string that is the suffix for the counter style in question
(which may be empty).</li>
<li>Otherwise the computed value is ''none''.</li>
</ol>
<div class="example">
<p>Given the following style sheet:</p>
<pre>li { display: list-item; list-style-type: decimal /* initial value */; }
li::marker { content: normal /* initial value */; }</pre>
<p>And the following document fragment:</p>
<pre><li> List Item </li></pre>
<p>The computed value of the 'content' property on the ''::marker''
pseudo-element of the list item element is:</p>
<pre>counter(list-item, decimal) "."</pre>
</div>
<!-- ====================================================================== -->
<h2 id=list-style-position-property>
Marker Position: The 'list-style-position' property</h2>
<table class="propdef">
<tr>
<th>Name:
<td><dfn>list-style-position</dfn>
<tr>
<th>Value:
<td>inside | hanging | outside
<tr>
<th>Initial:
<td>outside
<tr>
<th>Applies To:
<td>all elements with ''display: list-item''
<tr>
<th>Inherited:
<td>yes
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed Value:
<td>specified value
</table>
<p>This property specifies the position of the ''::marker'' pseudo-element's box
in the list item. Values have the following meanings:</p>
<dl>
<dt><dfn>inside</dfn></dt>
<dd>The ''::marker'' pseudo-element is an inline-block element placed immediately
before the ''::before'' pseudo-element in the list item's principle box, after
which the element's content flows. Note that if there is no inline content,
this will create a line box, just as content in an inline ''::before'' pseudo-element
would. Also note that all the properties that apply to inline elements apply
to the ''::marker'' pseudo-element in this state, and this ''::marker'' box
participates in the inline box model in the normal manner.</dd>
<dt><dfn>hanging</dfn></dt>
<dd>As ''inside'', except the marker is absolutely positioned (see the section
on ''::marker'' for more details.) The marker's auto position is such that
its "before" edge is aligned with the "before" edge of the first line box
in the list item, and its "end" edge is flush with the "start" edge of the
first line box in the list item.
<span class=note>Note that this causes the marker to still respond to the
'text-align' property, as the boundaries of line boxes depend on 'text-align'.</span></dd>
<dt><dfn>outside</dfn></dt>
<dd>As ''inside'', except the marker is absolutely positioned (see the section
on ''::marker'' for more details.) The marker's auto position is such that
its "before" edge is aligned with the "before" edge of the list item. If
the list item's parent box is ltr, the marker's "end" edge must be flush
with the list item's "start" edge; if the list item's parent box is rtl,
the marker's "start" edge must be flush with the list item's "end" edge.</dd>
</dl>
<div class=issue>
<p>''hanging'' is meant to emulate what some browsers (IE8, Firefox, Opera)
did for the CSS2.1 "outside" value, with somewhat more detail.</p>
<p>''outside'' is meant to emulate what other browsers (Webkit, IE9) did for
the CSS2.1 "outside" value, again with more detail. There is a notable behavior
change, in that the markers pay attention to the container's direction, not
the list item. This arose from the "Requirements for bidi in HTML" group's
conclusions - in a mixed-direction list, right now it's impossible to determine
ahead of time which side of the container the gutter should go (to contain the
bullet). You have to put a gutter on both sides, even if all the items are
one direction, just in case.</p>
<p>I'm not sure exactly how to express what I want with the "out-of-flow" comment
in ''hanging'' and ''outside''. I want to change how it's positioned, but
without invoking the "positioned element" machinery. Is that good/possible?
I also don't want to interfere with the author actually setting 'position' on
''::marker''. All this, and the ''::marker'' should still be a child of the
list item in the box tree (otherwise the behavior is surprising).</p>
<p>How should I define "first line box" for ''hanging''? The marker is intended
to be "magically positioned" - does this invoke the same logic that Positioned
Layout defines, where it leaves behind an inline placeholder that will generate
a line box? If not, do I descend into children to find the first linebox?
If I do that, there's the possibility of conflict, if a list item contains a
list item, and both of their markers position off of the same linebox. The
consequences of this are well-defined, but is that okay? I get 3 different
behaviors out of the 3 hanging-like browsers.</p>
</div>
<p>Note that a marker is only generated if the computed value of the 'content'
property for the element's ''::marker'' pseudo-element is not ''inhibit''.</p>
<div class="html-example">
<p>For example:
<pre>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<HTML>
<HEAD>
<TITLE>Comparison of inside/outside position</TITLE>
<STYLE type="text/css">
UL { list-style: outside }
UL.compact { list-style: inside }
</STYLE>
</HEAD>
<BODY>
<UL>
<LI>first list item comes first</LI>
<LI>second list item comes second</LI>
</UL>
<HT>
<UL class="compact">
<LI>first list item comes first</LI>
<LI>second list item comes second</LI>
</UL>
</BODY>
</HTML>
</pre>
<p> The above example may be formatted as:</p>
<div class="figure">
<p><img id="img-list-inout" src="list-inout.gif" alt="list with bullets to the left of it and list with bullets inside"></p>
</div>
</div>
<p>In right-to-left text, the markers would have been on the right side of the box.</p>
<!-- ====================================================================== -->
<h2 id=list-style-property>
The 'list-style' shorthand property</h2>
<table class="propdef">
<tr>
<th>Name:
<td><dfn>list-style</dfn>
<tr>
<th>Value:
<td><'list-style-type'> || <'list-style-position'> || <'list-style-image'>
<tr>
<th>Initial:
<td>N/A (shorthand property)
<tr>
<th>Applies To:
<td>all elements with ''display: list-item''
<tr>
<th>Media:
<td>visual
<tr>
<th>Computed Value;
<td>N/A (shorthand property)
</table>
<p>The 'list-style' property is a shorthand notation for setting the
three properties 'list-style-type', 'list-style-image', and 'list-style-position'
at the same place in the style sheet.</p>
<div class="example">
<p>For example:</p>
<pre>
UL { list-style: upper-roman inside } /* Any UL */
UL > UL { list-style: circle outside } /* Any UL child of a UL */
</pre>
</div>
<p>Although authors may specify 'list-style' information directly on
list item elements (e.g., LI in HTML), they should do so with care. The following rules look
similar, but the first declares a descendant selector and the second a (more specific) child selector.</p>
<pre class="example">
OL.alpha LI { list-style: lower-alpha } /* Any LI descendant of an OL */
OL.alpha > LI { list-style: lower-alpha } /* Any LI child of an OL */
</pre>
<p>Authors who use only the descendant selector may not
achieve the results they expect. Consider the following rules:</p>
<pre class="html-example">
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
<HTML>
<HEAD>
<TITLE>WARNING: Unexpected results due to cascade</TITLE>
<STYLE type="text/css">
OL.alpha LI { list-style: lower-alpha }
UL LI { list-style: disc }
</STYLE>
</HEAD>
<BODY>
<OL class="alpha">
<LI>level 1
<UL>
<LI>level 2</LI>
</UL>
</LI>
</OL>
</BODY>
</HTML>
</pre>
<p>The desired rendering would have level 1 list items with 'lower-alpha' labels and level 2 items
with 'disc' labels. However, the cascading order will cause the first style rule (which includes
specific class information) to mask the second. The following rules solve the problem by employing a
child selector instead:</p>
<pre class="example">
OL.alpha > LI { list-style: lower-alpha }
UL LI { list-style: disc }
</pre>
<p>Another solution would be to specify 'list-style' information only
on the list type elements:
<pre class="example">
OL.alpha { list-style: lower-alpha }
UL { list-style: disc }
</pre>
<p>Inheritance will transfer the 'list-style' values from OL and UL
elements to LI elements. This is the recommended way to specify list style information.</p>
<div class="example">
<p> A URI value may be combined with any other value, as in:</p>
<pre>
UL { list-style: url("http://png.com/ellipse.png") disc }
</pre>
<p> In the example above, the 'disc' will be used when the image is unavailable.</p>
</div>
<p>A value of ''none'' for the 'list-style' property sets both 'list-style-type'
and 'list-style-image' to ''none'', because it sets the 'list-style-type' to ''none''
(that is the first value in the list), and the initial value of the 'list-style-image'
property, which isn't listed in that declaration, is ''none''. For this reason,</p>
<pre>LI { list-style: none; }</pre>
<p>will ensure that no list-item marker is displayed on LI elements, except if a value is explicitly
given to the 'content' property of the ''::marker'' pseudo-element. In general, the best way to ensure that no marker
is rendered is to not set the 'display' property to list-item.</p>
<!-- ====================================================================== -->
<h2 id=marker-pseudoelement>
Markers: The ''::marker'' pseudo-element</h2>
<p>Markers are created by setting an element's 'display' property to
''list-item''. The ''list-item'' display type is, in every
other respect, identical to the ''block'' display type. The marker box is only
created if the computed value of the 'content' property for the pseudo-element
is not ''none''.</p>