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<!DOCTYPE html>
<html lang=en>
<head>
<meta content="text/html; charset=utf-8" http-equiv=Content-Type>
<title>CSS Scroll Snap Points Module 1</title>
<link href="#contents" rel=contents>
<link href="#index" rel=index>
<link href="../default.css" rel=stylesheet type="text/css">
<link href="../csslogo.ico" rel="shortcut icon" type="image/x-icon">
<link href="http://www.w3.org/StyleSheets/TR/W3C-ED.css" rel=stylesheet
type="text/css">
<body class=h-entry>
<div class=head> <!--begin-logo-->
<p id=x><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 class=p-name>CSS Scroll Snap Points Module Level 1</h1>
<h2 class="no-num no-toc">Editor's Draft <time class=dt-updated
datetime=20131028>28 October 2013</time>
<!-- for HTML4.x doctypes: <span class="dt-updated"><span class="value-title" title="20131028">28 October 2013</span></span> -->
</h2>
<dl>
<dt>This version:
<dd><a class=u-url
href="http://dev.w3.org/csswg/css-snappoints/">http://dev.w3.org/csswg/css-snappoints/</a>
<dt>Latest version:
<dd><a
href="http://www.w3.org/TR/css-snappoints/">http://www.w3.org/TR/css-snappoints/</a>
<!-- <dt>Editor's draft:
<dd><a href="http://dev.w3.org/csswg/css-snappoints/">http://dev.w3.org/csswg/css-snappoints/</a>
(<a href="https://dvcs.w3.org/hg/csswg/log/tip/css-snappoints/Overview.src.html">change log</a>)
<dt>Previous version:
<dd><a href="http://www.w3.org/PreviousVersionURI">http://www.w3.org/PreviousVersionURI</a>
-->
<dt>Issue Tracking:
<dd><a href="http://wiki.csswg.org/spec/css-snappoints"
rel=issues>http://wiki.csswg.org/spec/css-snappoints</a>
<dt>Feedback:
<dd><a
href="mailto:www-style@w3.org?subject=%5BSHORTNAME%5D%20feedback">www-style@w3.org</a>
with subject line “<kbd>[css-snappoints] <var>… message topic
…</var></kbd>” (<a
href="http://lists.w3.org/Archives/Public/www-style/"
rel=discussion>archives</a>)
<dt>Editors:
<dd class="p-author h-card vcard"><span class="p-name fn">Matt
Rakow</span>, <a class="p-org org h-org"
href="http://www.microsoft.com/">Microsoft Corporation</a>
<dd class="p-author h-card vcard"><span class="p-name fn">Jacob
Rossi</span>, <a class="p-org org h-org"
href="http://www.microsoft.com/">Microsoft Corporation</a>
</dl>
<!--begin-copyright-->
<p class=copyright id=copyright-copy-year-2000-w3creg-mit-erci><a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"
rel=license>Copyright</a> © 2013 <a href="http://www.w3.org/"><abbr
title="World Wide Web Consortium">W3C</abbr></a><sup>®</sup> (<a
href="http://www.csail.mit.edu/"><abbr
title="Massachusetts Institute of Technology">MIT</abbr></a>, <a
href="http://www.ercim.eu/"><abbr
title="European Research Consortium for Informatics and Mathematics">ERCIM</abbr></a>,
<a href="http://www.keio.ac.jp/">Keio</a>, <a
href="http://ev.buaa.edu.cn/">Beihang</a>), All Rights Reserved. W3C <a
href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>,
<a
href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>
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 id=css-is-a-language-for-describing-the-ren> <span class=p-summary> <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. This module contains the features of CSS to control
panning and scrolling behavior with "snap points." </span>
<h2 class="no-num no-toc" id=status>Status of this document</h2>
<!--begin-status-->
<p id=this-is-a-public-copy-of-the-editors-dra>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 id=the-archived-public-mailing-list-www-sty>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-snappoints%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-snappoints” in the subject, preferably like this:
“[<!---->css-snappoints<!---->] <em>…summary of comment…</em>”
<p id=this-document-was-produced-by-the-css-wo>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 id=this-document-was-produced-by-a-group-op>This document was produced
by a group operating under the <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February
2004 W3C Patent Policy</a>. W3C maintains a <a
href="http://www.w3.org/2004/01/pp-impl/32061/status"
rel=disclosure>public list of any patent disclosures</a> made in
connection with the deliverables of the group; that page also includes
instructions for disclosing a patent. An individual who has actual
knowledge of a patent which the individual believes contains <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential
Claim(s)</a> must disclose the information in accordance with <a
href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section
6 of the W3C Patent Policy</a>.</p>
<!--end-status-->
<h2 class="no-num no-toc" id=contents> Table of Contents</h2>
<!--begin-toc-->
<ul class=toc>
<li id=introduction-1.1.-module-interactions-1.><a href="#intro"><span
class=secno>1. </span> Introduction</a>
<ul class=toc>
<li id=module-interactions-><a href="#placement"><span class=secno>1.1.
</span> Module interactions</a>
<li id=values-><a href="#values"><span class=secno>1.2. </span>
Values</a>
</ul>
<li id=examples-><a href="#examples"><span class=secno>2. </span>Examples
</a>
<li id=definitions-><a href="#definitions"><span class=secno>3. </span>
Definitions</a>
<li id=scroll-snap-types-the-scroll-snap-type-p><a
href="#scroll-snap-type"><span class=secno>4. </span> Scroll Snap Types:
the ‘<code class=property>scroll-snap-type</code>’ property</a>
<li id=scroll-snap-points-the-scroll-snap-point><a
href="#scroll-snap-points"><span class=secno>5. </span> Scroll Snap
Points: the ‘<code class=property>scroll-snap-points-x</code>’ and
‘<code class=css>scroll-snap-points-y properties</code></a>
<li id=conformance-6.1.-document-conventions-6.><a
href="#conformance"><span class=secno>6. </span> Conformance</a>
<ul class=toc>
<li id=document-conventions-><a href="#conventions"><span
class=secno>6.1. </span> Document conventions</a>
<li id=conformance-classes-><a href="#conformance-classes"><span
class=secno>6.2. </span> Conformance classes</a>
<li id=partial-implementations-><a href="#partial"><span
class=secno>6.3. </span> Partial implementations</a>
<li id=experimental-implementations-><a href="#experimental"><span
class=secno>6.4. </span> Experimental implementations</a>
<li id=non-experimental-implementations-><a href="#testing"><span
class=secno>6.5. </span> Non-experimental implementations</a>
</ul>
<li class=no-num id=acknowledgments-><a href="#acknowledgments">
Acknowledgments</a>
<li class=no-num id=references-normative-references-other-re><a
href="#references"> References</a>
<ul class=toc>
<li class=no-num id=normative-references-><a
href="#normative-references"> Normative references</a>
<li class=no-num id=other-references-><a href="#other-references"> Other
references</a>
</ul>
<li class=no-num id=index-><a href="#index"> Index</a>
<li class=no-num id=property-index0><a href="#property-index"> Property
index</a>
</ul>
<!--end-toc-->
<h2 id=intro><span class=secno>1. </span> Introduction</h2>
<p id=this-section-is-not-normative.><em>This section is not
normative.</em>
<p id=popular-ux-paradigms-for-scrollable-cont>Popular UX paradigms for
scrollable content frequently employ pagination of content, or sectioning
into logical divisions. This is especially true for touch interactions
where it is quicker and easier for users to quickly pan through a
flatly-arranged breadth of content rather than delving into a heirarchical
structure through tap navigation. For example, it is easier for a user
view many photos in a photo album by panning through a photo slideshow
view rather than tapping on individual photos in an album.
<p id=however-given-the-imprecise-nature-of-sc>However, given the imprecise
nature of scrolling inputs like touch panning and mousewheel scrolling, it
is difficult for web developers to guarantee a well-controlled scrolling
experience, in particular creating the effect of pagination. For instance,
it is easy for a user to land at an awkward scroll offset which leaves a
page partially on-screen when panning.
<p id=to-this-end-we-introduce-scroll-snap-poi>To this end, we introduce
scroll snap points which enforce the scroll offsets that a scroller may
end at after a scrolling operation has completed.
<h3 id=placement><span class=secno>1.1. </span> Module interactions</h3>
<p id=this-module-extends-the-scrolling-user-i>This module extends the
scrolling user interface features defined in <a
href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a> section 11.1.
<p id=none-of-the-properties-in-this-module-ap>None of the properties in
this module apply to the <code>::first-line</code> and
<code>::first-letter</code> pseudo-elements.
<h3 id=values><span class=secno>1.2. </span> Values</h3>
<p id=this-specification-follows-the-css-prope>This specification follows
the <a href="http://www.w3.org/TR/CSS21/about.html#property-defs">CSS
property definition conventions</a> from <a
href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a>. Value types not defined in
this specification are defined in CSS Level 2 Revision 1 <a
href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a>. Other CSS modules may
expand the definitions of these value types: for example <a
href="#ref-CSS3VAL">[CSS3VAL]<!--{{CSS3VAL}}--></a>, when combined with
this module, expands the definition of the <var><length></var> value
type as used in this specification.
<p id=in-addition-to-the-property-specific-val>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=examples><span class=secno>2. </span>Examples</h2>
<div class=example>
<p id=in-this-example-a-series-of-images-arran>In this example, a series
of images arranged in a <a href="#scroller">scroller</a> are used to
build a photo gallery. The <a href="#scroller">scroller</a> is sized to
the same size of the images contained therein. Using mandatory snap
points, scrolling will always complete with a snap point aligned to the
edge of the <a href="#scroller">scroller</a>. By aligning a snap point at
the edge of each image, this creates a photo viewer were users can scroll
through the images one at a time.
<pre>img {
width:500px;
}
.photoGallery {
width: 500px;
overflow-x: auto;
overflow-y: hidden;
white-space: nowrap;
scroll-snap-points-x: snapInterval(0px,100%); /*Sets up points to which scrolling will snap along x-axis */
scroll-snap-type: mandatory; /* requires that scrolling always end at a snap point when the operation completes (hard snap) */
}</pre>
<code class=html><div class="photoGallery"> <img
src="img1.jpg"><img src="img2.jpg"><img
src="img3.jpg"><img src="img4.jpg"><img
src="img5.jpg"> </div></code>
<div class=figure>
<p id=x0><img
alt="The layout of the scroller</code>’s contents in the example. Snap points are set along the x-axis, starting at 0px and repeating at intervals of 100% of the containing block's width."
src=example1.png>
<p class=caption id=the-layout-of-the-scrollers-contents-in->The layout
of the scroller's contents in the example. Snap points are set along the
x-axis, starting at 0px and repeating at intervals of 100% of the
containing block's width.
</div>
</div>
<h2 id=definitions><span class=secno>3. </span> Definitions</h2>
<dl>
<dt><dfn id=scroller>scroller</dfn>
<dd>An element which provides a scrolling user interface as described in
<a href="#ref-CSS21">[CSS21]<!--{{!CSS21}}--></a>, particularly in the
section on overflow.
</dl>
<h2 id=scroll-snap-type><span class=secno>4. </span> Scroll Snap Types: the
‘<a href="#scroll-snap-type0"><code
class=property>scroll-snap-type</code></a>’ property</h2>
<p id=the-scroll-snap-type-property-is-used-to>The ‘<a
href="#scroll-snap-type0"><code class=css>scroll-snap-type</code></a>’
property is used to define the physics characteristics of panning and
scrolling, if any. It defines how and when snap points are enforced on the
scroller it is applied to.
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=scroll-snap-type0>scroll-snap-type</dfn>
<tr>
<th><a href="#values">Value</a>:
<td>none | mandatory | proximity
<tr>
<th>Initial:
<td>none
<tr>
<th>Applies to:
<td>block-level <a class=index-def href="#scroller"
id=scrollers>scrollers</a>
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>N/A
<tr>
<th>Media:
<td>interactive
<tr>
<th>Computed value:
<td>specified value
<tr>
<th>Animatable:
<td>no
<tr>
<th>Canonical order:
<td><abbr title="follows order of property value definition">per
grammar</abbr>
</table>
<dl>
<dt><dfn id=none>‘<code class=css>none</code>’</dfn>
<dd>This <a href="#scroller">scroller</a> <strong>must</strong> ignore
snap points, if any, when scrolled.
<dt><dfn id=mandatory>‘<code class=css>mandatory</code>’</dfn>
<dd>This <a href="#scroller">scroller</a> <strong>must</strong> come to
rest on a snap point at the termination of a scroll, if possible.
<dt><dfn id=proximity>‘<code class=css>proximity</code>’</dfn>
<dd>This <a href="#scroller">scroller</a> <strong>may</strong> come to
rest on a snap point at the termination of a scroll at the discretion of
the UA given the parameters of the scroll.
</dl>
<h2 id=scroll-snap-points><span class=secno>5. </span> Scroll Snap Points:
the ‘<a href="#scroll-snap-points-x"><code
class=property>scroll-snap-points-x</code></a>’ and ‘<code
class=css>scroll-snap-points-y properties</code></h2>
<p id=the-scroll-snap-points-x-and-scroll-snap>The ’‘<a
href="#scroll-snap-points-x"><code
class=property>scroll-snap-points-x</code></a>’‘<code class=css> and
</code>’‘<a href="#scroll-snap-points-y"><code
class=property>scroll-snap-points-y</code></a>’‘<code class=css>
properties are used to define the positioning of snap points within the
content of the <a href="#scroller">scroller</a> they are applied to.
</code>
<table class=propdef>
<tbody>
<tr>
<th>Name:
<td><dfn id=scroll-snap-points-x>scroll-snap-points-x</dfn>, <dfn
id=scroll-snap-points-y>scroll-snap-points-y</dfn>
<tr>
<th><a href="#values">Value</a>:
<td>snapInterval(<length>,<length>) | snapList(<length>[,<length>]*)
<tr>
<th>Initial:
<td>snapInterval(0px, 100%)
<tr>
<th>Applies to:
<td>block-level <a class=index-def href="#scroller"
id=scrollers0>scrollers</a>
<tr>
<th>Inherited:
<td>no
<tr>
<th>Percentages:
<td>Refer to the padding-box of the <a href="#scroller">scroller</a>
<tr>
<th>Media:
<td>interactive
<tr>
<th>Computed value:
<td>specified value
<tr>
<th>Animatable:
<td>no
<tr>
<th>Canonical order:
<td><abbr title="follows order of property value definition">per
grammar</abbr>
</length></length></length></length>
</table>
<dl>
<dt><dfn id=snaplistpoint1point2>’‘<code
class=css>snapList(point1,point2,…)</code>’‘<code
class=css></code></dfn>
<dd>Defines one or more discrete snap points for the <a
href="#scroller">scroller</a>.
<dt><dfn id=snapintervalstart-interval->’‘<code
class=css>snapInterval(start, interval) </code>’‘<code
class=css></code></dfn>
<dd>Defines a starting snap point and an interval at which additional snap
points are defined. The first argument is the starting snap point and the
second argument is the interval to repeat thereafter.
</dl>
<h2 id=conformance><span class=secno>6. </span> Conformance</h2>
<h3 id=conventions><span class=secno>6.1. </span> Document conventions</h3>
<p id=conformance-requirements-are-expressed-w>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 id=all-of-the-text-of-this-specification-is>All of the text of this
specification is normative except sections explicitly marked as
non-normative, examples, and notes. <a
href="#ref-RFC2119">[RFC2119]<!--{{!RFC2119}}--></a>
<p id=examples-in-this-specification-are-intro>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 id=this-is-an-example-of-an-informative-exa>This is an example of an
informative example.
</div>
<p id=informative-notes-begin-with-the-word-no>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 id=note-this-is-an-informative-note.>Note, this is an
informative note.
<h3 id=conformance-classes><span class=secno>6.2. </span> Conformance
classes</h3>
<p id=conformance-to-css-scroll-snap-points-mo>Conformance to CSS Scroll
Snap Points Module 1 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 id=a-style-sheet-is-conformant-to-css-scrol>A style sheet is conformant
to CSS Scroll Snap Points Module 1 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 id=a-renderer-is-conformant-to-css-scroll-s>A renderer is conformant to
CSS Scroll Snap Points Module 1 if, in addition to interpreting the style
sheet as defined by the appropriate specifications, it supports all the
features defined by CSS Scroll Snap Points Module 1 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 id=an-authoring-tool-is-conformant-to-css-s>An authoring tool is
conformant to CSS Scroll Snap Points Module 1 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>6.3. </span> Partial implementations</h3>
<p id=so-that-authors-can-exploit-the-forward->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>6.4. </span> Experimental
implementations</h3>
<p id=to-avoid-clashes-with-future-css-feature>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 id=prior-to-a-specification-reaching-the-ca>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>6.5. </span> Non-experimental
implementations</h3>
<p id=once-a-specification-reaches-the-candida>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 id=to-establish-and-maintain-the-interopera>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 id=further-information-on-submitting-testca>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.
<h2 class=no-num id=acknowledgments> Acknowledgments</h2>
<p id=many-thanks-to-lots-of-people-for-their->Many thanks to lots of
people for their proposals and recommendations, some of which are
incorporated into this document.
<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 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=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 id=CSS3VAL>[CSS3VAL]
<dd>Håkon Wium Lie; Tab Atkins; Elika J. Etemad. <a
href="http://www.w3.org/TR/2013/CR-css3-values-20130730/"><cite>CSS
Values and Units Module Level 3.</cite></a> 30 July 2013. W3C Candidate
Recommendation. (Work in progress.) URL: <a
href="http://www.w3.org/TR/2013/CR-css3-values-20130730/">http://www.w3.org/TR/2013/CR-css3-values-20130730/</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="section 6.2."><strong>6.2.</strong></a>
<li>‘<code class=css>mandatory</code>’, <a href="#mandatory"
title="section 4."><strong>4.</strong></a>
<li>‘<code class=css>none</code>’, <a href="#none"
title="section 4."><strong>4.</strong></a>
<li>‘<code class=css>proximity</code>’, <a href="#proximity"
title="section 4."><strong>4.</strong></a>
<li>renderer, <a href="#renderer"
title="section 6.2."><strong>6.2.</strong></a>
<li>scroller, <a href="#scroller"
title="section 3."><strong>3.</strong></a>
<li>scrollers, <a href="#scrollers"
title="section 4."><strong>4.</strong></a>, <a href="#scrollers0"
title="section 5."><strong>5.</strong></a>
<li>scroll-snap-points-x, <a href="#scroll-snap-points-x"
title="section 5."><strong>5.</strong></a>
<li>scroll-snap-points-y, <a href="#scroll-snap-points-y"
title="section 5."><strong>5.</strong></a>
<li>scroll-snap-type, <a href="#scroll-snap-type0"
title="section 4."><strong>4.</strong></a>
<li>’‘<code class=css>snapInterval(start, interval) </code>’‘<code
class=css></code>, <a href="#snapintervalstart-interval-"
title="section 5."><strong>5.</strong></a>
<li>’‘<code class=css>snapList(point1,point2,…)</code>’‘<code
class=css></code>, <a href="#snaplistpoint1point2"
title="section 5."><strong>5.</strong></a>
<li>style sheet
<ul>
<li>as conformance class, <a href="#style-sheet"
title="section 6.2."><strong>6.2.</strong></a>
</ul>
</ul>
<!--end-index-->
<h2 class=no-num id=property-index> Property index</h2>
<!--begin-properties-->
<table class=proptable>
<thead>
<tr>
<th>Property
<th>Values
<th>Initial
<th>Applies to
<th>Inh.
<th>Percentages
<th>Media
<tbody>
<tr>
<th><a class=property
href="#scroll-snap-points-x">scroll-snap-points-x</a>
<td>snapInterval(,) | snapList([,]*)
<td>snapInterval(0px, 100%)
<td>block-level scrollers
<td>no
<td>Refer to the padding-box of the scroller
<td>interactive
<tr>
<th><a class=property
href="#scroll-snap-points-y">scroll-snap-points-y</a>
<td>snapInterval(,) | snapList([,]*)
<td>snapInterval(0px, 100%)
<td>block-level scrollers
<td>no
<td>Refer to the padding-box of the scroller
<td>interactive
<tr>
<th><a class=property href="#scroll-snap-type0">scroll-snap-type</a>
<td>none | mandatory | proximity
<td>none
<td>block-level scrollers
<td>no
<td>N/A
<td>interactive
</table>
<!--end-properties-->
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