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<!DOCTYPE html><html lang=en><head>
<meta content="text/html; charset=utf-8" http-equiv=Content-Type>
<title>CSS Grid Layout Module Level 1</title>
<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>
<style type=text/css>
.example {
clear:both
}
.pseudo-code {
font-family:monospace
}
.pseudo-code > ol {
list-style-type:decimal
}
.pseudo-code > ol > li > ol {
list-style-type:lower-latin
}
.pseudo-code > ol > li > ol > li > ol {
list-style-type:lower-roman
}
.pseudo-code ul {
list-style-type:disc
}
dd > p:nth-child(1) {
margin-top:0
}
dd:last-child {
margin-bottom: 0;
}
dl.phase {
padding-left: .5em;
border-left: .5em #e0e0e0 solid;
}
</style>
<script>self = (typeof window !== 'undefined')
? window // if in browser
: (
(typeof WorkerGlobalScope !== 'undefined' && self instanceof WorkerGlobalScope)
? self // if in worker
: {} // if in node js
);
/**
* Prism: Lightweight, robust, elegant syntax highlighting
* MIT license http://www.opensource.org/licenses/mit-license.php/
* @author Lea Verou http://lea.verou.me
*/
var Prism = (function(){
// Private helper vars
var lang = /\blang(?:uage)?-(?!\*)(\w+)\b/i;
var _ = self.Prism = {
util: {
encode: function (tokens) {
if (tokens instanceof Token) {
return new Token(tokens.type, _.util.encode(tokens.content), tokens.alias);
} else if (_.util.type(tokens) === 'Array') {
return tokens.map(_.util.encode);
} else {
return tokens.replace(/&/g, '&').replace(/</g, '<').replace(/\u00a0/g, ' ');
}
},
type: function (o) {
return Object.prototype.toString.call(o).match(/\[object (\w+)\]/)[1];
},
// Deep clone a language definition (e.g. to extend it)
clone: function (o) {
var type = _.util.type(o);
switch (type) {
case 'Object':
var clone = {};
for (var key in o) {
if (o.hasOwnProperty(key)) {
clone[key] = _.util.clone(o[key]);
}
}
return clone;
case 'Array':
return o.slice();
}
return o;
}
},
languages: {
extend: function (id, redef) {
var lang = _.util.clone(_.languages[id]);
for (var key in redef) {
lang[key] = redef[key];
}
return lang;
},
// Insert a token before another token in a language literal
insertBefore: function (inside, before, insert, root) {
root = root || _.languages;
var grammar = root[inside];
var ret = {};
for (var token in grammar) {
if (grammar.hasOwnProperty(token)) {
if (token == before) {
for (var newToken in insert) {
if (insert.hasOwnProperty(newToken)) {
ret[newToken] = insert[newToken];
}
}
}
ret[token] = grammar[token];
}
}
return root[inside] = ret;
},
// Traverse a language definition with Depth First Search
DFS: function(o, callback, type) {
for (var i in o) {
if (o.hasOwnProperty(i)) {
callback.call(o, i, o[i], type || i);
if (_.util.type(o[i]) === 'Object') {
_.languages.DFS(o[i], callback);
} else if (_.util.type(o[i]) === 'Array') {
_.languages.DFS(o[i], callback, i);
}
}
}
}
},
highlightAll: function(async, callback) {
var elements = document.querySelectorAll('code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code');
for (var i=0, element; element = elements[i++];) {
if (element.classList.contains("idl")) {
// Bikeshed handles IDL blocks already.
continue;
}
_.highlightElement(element, async === true, callback);
}
var elements = document.querySelectorAll('pre[class*="language-"], [class*="language-"] pre, pre[class*="lang-"], [class*="lang-"] pre');
for (var i=0, element; element = elements[i++];) {
if (element.firstElementChild && element.firstElementChild.tagName.toLowerCase() == "code") {
// Already handled by the previous loop
continue;
}
if (element.classList.contains("idl")) {
// Bikeshed handles IDL blocks already.
continue;
}
_.highlightElement(element, async === true, callback);
}
},
highlightElement: function(element, async, callback) {
// Find language
var language, grammar, parent = element;
while (parent && !lang.test(parent.className)) {
parent = parent.parentNode;
}
if (parent) {
language = (parent.className.match(lang) || [,''])[1];
grammar = _.languages[language];
}
if (!grammar) {
return;
}
// Set language on the element, if not present
element.className = element.className.replace(lang, '').replace(/\s+/g, ' ') + ' language-' + language;
// Set language on the parent, for styling
parent = element.parentNode;
if (/pre/i.test(parent.nodeName)) {
parent.className = parent.className.replace(lang, '').replace(/\s+/g, ' ') + ' language-' + language;
}
var code = element.textContent;
if(!code) {
return;
}
var env = {
element: element,
language: language,
grammar: grammar,
code: code
};
_.hooks.run('before-highlight', env);
if (async && self.Worker) {
var worker = new Worker(_.filename);
worker.onmessage = function(evt) {
env.highlightedCode = Token.stringify(JSON.parse(evt.data), language);
_.hooks.run('before-insert', env);
env.element.innerHTML = env.highlightedCode;
callback && callback.call(env.element);
_.hooks.run('after-highlight', env);
};
worker.postMessage(JSON.stringify({
language: env.language,
code: env.code
}));
}
else {
env.highlightedCode = _.highlight(env.code, env.grammar, env.language)
_.hooks.run('before-insert', env);
env.element.innerHTML = env.highlightedCode;
callback && callback.call(element);
_.hooks.run('after-highlight', env);
}
},
highlight: function (text, grammar, language) {
var tokens = _.tokenize(text, grammar);
return Token.stringify(_.util.encode(tokens), language);
},
tokenize: function(text, grammar, language) {
var Token = _.Token;
var strarr = [text];
var rest = grammar.rest;
if (rest) {
for (var token in rest) {
grammar[token] = rest[token];
}
delete grammar.rest;
}
tokenloop: for (var token in grammar) {
if(!grammar.hasOwnProperty(token) || !grammar[token]) {
continue;
}
var patterns = grammar[token];
patterns = (_.util.type(patterns) === "Array") ? patterns : [patterns];
for (var j = 0; j < patterns.length; ++j) {
var pattern = patterns[j],
inside = pattern.inside,
lookbehind = !!pattern.lookbehind,
lookbehindLength = 0,
alias = pattern.alias;
pattern = pattern.pattern || pattern;
for (var i=0; i<strarr.length; i++) { // Don’t cache length as it changes during the loop
var str = strarr[i];
if (strarr.length > text.length) {
// Something went terribly wrong, ABORT, ABORT!
break tokenloop;
}
if (str instanceof Token) {
continue;
}
pattern.lastIndex = 0;
var match = pattern.exec(str);
if (match) {
if(lookbehind) {
lookbehindLength = match[1].length;
}
var from = match.index - 1 + lookbehindLength,
match = match[0].slice(lookbehindLength),
len = match.length,
to = from + len,
before = str.slice(0, from + 1),
after = str.slice(to + 1);
var args = [i, 1];
if (before) {
args.push(before);
}
var wrapped = new Token(token, inside? _.tokenize(match, inside) : match, alias);
args.push(wrapped);
if (after) {
args.push(after);
}
Array.prototype.splice.apply(strarr, args);
}
}
}
}
return strarr;
},
hooks: {
all: {},
add: function (name, callback) {
var hooks = _.hooks.all;
hooks[name] = hooks[name] || [];
hooks[name].push(callback);
},
run: function (name, env) {
var callbacks = _.hooks.all[name];
if (!callbacks || !callbacks.length) {
return;
}
for (var i=0, callback; callback = callbacks[i++];) {
callback(env);
}
}
}
};
var Token = _.Token = function(type, content, alias) {
this.type = type;
this.content = content;
this.alias = alias;
};
Token.stringify = function(o, language, parent) {
if (typeof o == 'string') {
return o;
}
if (Object.prototype.toString.call(o) == '[object Array]') {
return o.map(function(element) {
return Token.stringify(element, language, o);
}).join('');
}
var env = {
type: o.type,
content: Token.stringify(o.content, language, parent),
tag: 'span',
classes: ['token', o.type],
attributes: {},
language: language,
parent: parent
};
if (env.type == 'comment') {
env.attributes['spellcheck'] = 'true';
}
if (o.alias) {
var aliases = _.util.type(o.alias) === 'Array' ? o.alias : [o.alias];
Array.prototype.push.apply(env.classes, aliases);
}
_.hooks.run('wrap', env);
var attributes = '';
for (var name in env.attributes) {
attributes += name + '="' + (env.attributes[name] || '') + '"';
}
return '<' + env.tag + ' class="' + env.classes.join(' ') + '" ' + attributes + '>' + env.content + '</' + env.tag + '>';
};
if (!self.document) {
if (!self.addEventListener) {
// in Node.js
return self.Prism;
}
// In worker
self.addEventListener('message', function(evt) {
var message = JSON.parse(evt.data),
lang = message.language,
code = message.code;
self.postMessage(JSON.stringify(_.util.encode(_.tokenize(code, _.languages[lang]))));
self.close();
}, false);
return self.Prism;
}
// Get current script and highlight
var script = document.getElementsByTagName('script');
script = script[script.length - 1];
if (script) {
_.filename = script.src;
if (document.addEventListener && !script.hasAttribute('data-manual')) {
document.addEventListener('DOMContentLoaded', _.highlightAll);
}
}
return self.Prism;
})();
if (typeof module !== 'undefined' && module.exports) {
module.exports = Prism;
}
;
Prism.languages.markup = {
'comment': /<!--[\w\W]*?-->/g,
'prolog': /<\?.+?\?>/,
'doctype': /<!DOCTYPE.+?>/,
'cdata': /<!\[CDATA\[[\w\W]*?]]>/i,
'tag': {
pattern: /<\/?[\w:-]+\s*(?:\s+[\w:-]+(?:=(?:("|')(\\?[\w\W])*?\1|[^\s'">=]+))?\s*)*\/?>/gi,
inside: {
'tag': {
pattern: /^<\/?[\w:-]+/i,
inside: {
'punctuation': /^<\/?/,
'namespace': /^[\w-]+?:/
}
},
'attr-value': {
pattern: /=(?:('|")[\w\W]*?(\1)|[^\s>]+)/gi,
inside: {
'punctuation': /=|>|"/g
}
},
'punctuation': /\/?>/g,
'attr-name': {
pattern: /[\w:-]+/g,
inside: {
'namespace': /^[\w-]+?:/
}
}
}
},
'entity': /\&#?[\da-z]{1,8};/gi
};
// Plugin to make entity title show the real entity, idea by Roman Komarov
Prism.hooks.add('wrap', function(env) {
if (env.type === 'entity') {
env.attributes['title'] = env.content.replace(/&/, '&');
}
});
;
Prism.languages.css = {
'comment': /\/\*[\w\W]*?\*\//g,
'atrule': {
pattern: /@[\w-]+?.*?(;|(?=\s*{))/gi,
inside: {
'punctuation': /[;:]/g
}
},
'url': /url\((["']?).*?\1\)/gi,
'selector': /[^\{\}\s][^\{\};]*(?=\s*\{)/g,
'property': /(\b|\B)[\w-]+(?=\s*:)/ig,
'string': /("|')(\\?.)*?\1/g,
'important': /\B!important\b/gi,
'punctuation': /[\{\};:]/g,
'function': /[-a-z0-9]+(?=\()/ig
};
if (Prism.languages.markup) {
Prism.languages.insertBefore('markup', 'tag', {
'style': {
pattern: /<style[\w\W]*?>[\w\W]*?<\/style>/ig,
inside: {
'tag': {
pattern: /<style[\w\W]*?>|<\/style>/ig,
inside: Prism.languages.markup.tag.inside
},
rest: Prism.languages.css
}
}
});
};
Prism.languages.css.selector = {
pattern: /[^\{\}\s][^\{\}]*(?=\s*\{)/g,
inside: {
'pseudo-element': /:(?:after|before|first-letter|first-line|selection)|::[-\w]+/g,
'pseudo-class': /:[-\w]+(?:\(.*\))?/g,
'class': /\.[-:\.\w]+/g,
'id': /#[-:\.\w]+/g
}
};
Prism.languages.insertBefore('css', 'ignore', {
'hexcode': /#[\da-f]{3,6}/gi,
'entity': /\\[\da-f]{1,8}/gi,
'number': /[\d%\.]+/g
});;
</script><style>/* http://prismjs.com/download.html?themes=prism&languages=clike */
/**
* prism.js default theme for JavaScript, CSS and HTML
* Based on dabblet (http://dabblet.com)
* @author Lea Verou
*/
code[class*="language-"],
pre[class*="language-"] {
color: black;
text-shadow: 0 1px white;
font-family: Consolas, Monaco, 'Andale Mono', monospace;
direction: ltr;
text-align: left;
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<p data-fill-with=logo><a class=logo href=http://www.w3.org/>
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<h1 class="p-name no-ref" id=title>CSS Grid Layout Module Level 1</h1>
<h2 class="no-num no-toc no-ref heading settled" id=subtitle><span class=content>Editor’s Draft,
<time class=dt-updated datetime=2014-12-18>18 December 2014</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-grid/>http://dev.w3.org/csswg/css-grid/</a><dt>Latest version:<dd><a href=http://www.w3.org/TR/css-grid-1/>http://www.w3.org/TR/css-grid-1/</a><dt>Previous Versions:<dd><a href=http://www.w3.org/TR/2014/WD-css-grid-1-20140513/ rel=previous>http://www.w3.org/TR/2014/WD-css-grid-1-20140513/</a><dd><a href=http://www.w3.org/TR/2014/WD-css-grid-1-20140123/ rel=previous>http://www.w3.org/TR/2014/WD-css-grid-1-20140123/</a><dd><a href=http://www.w3.org/TR/2013/WD-css3-grid-layout-20130402/ rel=previous>http://www.w3.org/TR/2013/WD-css3-grid-layout-20130402/</a><dd><a href=http://www.w3.org/TR/2012/WD-css3-grid-layout-20121106/ rel=previous>http://www.w3.org/TR/2012/WD-css3-grid-layout-20121106/</a><dt>Feedback:<dd><span><a href="mailto:www-style@w3.org?subject=%5Bcss-grid%5D%20feedback">www-style@w3.org</a> with subject line “<kbd>[css-grid] <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=#issues-index>Inline In Spec</a><dt class=editor>Editors:<dd class=editor><div class="p-author h-card vcard"><a class="p-name fn u-url url" href=http://www.xanthir.com/contact/>Tab Atkins Jr.</a> (<span class="p-org org">Google</span>)</div><dd class=editor><div class="p-author h-card vcard"><a class="p-name fn u-url url" href=http://fantasai.inkedblade.net/contact>fantasai</a> (<span class="p-org org">Mozilla</span>)</div><dd class=editor><div class="p-author h-card vcard"><a class="p-name fn u-email email" href=mailto:ratan@microsoft.com>Rossen Atanassov</a> (<span class="p-org org">Microsoft</span>)</div><dt>Former Editors:<dd><div class="p-author h-card vcard"><a class="p-name fn u-email email" href=mailto:alexmog@microsoft.com>Alex Mogilevsky</a> (<span class="p-org org">Microsoft Corporation</span>)</div><dd><div class="p-author h-card vcard"><a class="p-name fn u-email email" href=mailto:pcupp@microsoft.com>Phil Cupp</a> (<span class="p-org org">Microsoft Corporation</span>)</div><dt>Issues list:<dd><span><a href="https://www.w3.org/Bugs/Public/buglist.cgi?product=CSS&component=Grid+Layout&bug_status=NEW&bug_status=ASSIGNED&bug_status=REOPENED">In Bugzilla</a></span></dl></div>
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<p class=copyright data-fill-with=copyright><a href=http://www.w3.org/Consortium/Legal/ipr-notice#Copyright>Copyright</a> © 2014 <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.
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<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>This CSS module defines a two-dimensional grid-based layout system, optimized for user interface design. In the grid layout model, the children of a grid container can be positioned into arbitrary slots in a flexible or fixed predefined layout grid.</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>
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-grid%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-grid” in the subject,
preferably like this:
“[css-grid] <em>…summary of comment…</em>”
<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>
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>
This document is governed by the <a href=http://www.w3.org/2014/Process-20140801/>1 August 2014 W3C Process Document</a>.
</div>
<div data-fill-with=at-risk><p>The following features are at-risk, and may be dropped during the CR period:
<ul><li>the <a class=css data-link-for=grid-template-rows data-link-type=maybe href=#valdef-grid-template-rows-grid-template-columns-subgrid>subgrid</a> value of <a class=property data-link-type=propdesc href=#propdef-grid-template-columns>grid-template-columns</a> and <a class=property data-link-type=propdesc href=#propdef-grid-template-rows>grid-template-rows</a>, and its component parts individually</ul></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=#intro><span class=secno>1</span> <span class=content>
Introduction and Overview</span></a><ul class=toc><li><a href=#background><span class=secno>1.1</span> <span class=content>
Background and Motivation</span></a><li><a href=#adapting-to-available-space><span class=secno>1.2</span> <span class=content>
Adapting Layouts to Available Space</span></a><li><a href=#source-independence><span class=secno>1.3</span> <span class=content>
Source-Order Independence</span></a><li><a href=#grid-layering><span class=secno>1.4</span> <span class=content>
Grid Layering of Elements</span></a></ul><li><a href=#grid-concepts><span class=secno>2</span> <span class=content>
Grid Layout Concepts and Terminology</span></a><ul class=toc><li><a href=#grid-track-concept><span class=secno>2.1</span> <span class=content>
Grid Tracks and Cells</span></a><li><a href=#grid-line-concept><span class=secno>2.2</span> <span class=content>
Grid Lines</span></a><li><a href=#grid-area-concept><span class=secno>2.3</span> <span class=content>
Grid Areas</span></a></ul><li><a href=#grid-model><span class=secno>3</span> <span class=content>
Grid Containers</span></a><ul class=toc><li><a href=#grid-containers><span class=secno>3.1</span> <span class=content>
Establishing Grid Containers: the <span class=css data-link-for=display data-link-type=maybe title=grid>grid</span> and <span class=css data-link-type=maybe title=inline-grid>inline-grid</span> <span class=property data-link-type=propdesc title=display>display</span> values</span></a><li><a href=#intrinsic-sizes><span class=secno>3.2</span> <span class=content>
Sizing Grid Containers</span></a></ul><li><a href=#grid-items><span class=secno>4</span> <span class=content>
Grid Items</span></a><ul class=toc><li><a href=#visibility-collapse><span class=secno>4.1</span> <span class=content>
Collapsed Grid Items: the <span class=property data-link-type=propdesc title=visibility>visibility</span> property</span></a><li><a href=#order-property><span class=secno>4.2</span> <span class=content>
Reordered Grid Items: the <span class=property data-link-type=propdesc title=order>order</span> property</span></a><li><a href=#static-position><span class=secno>4.3</span> <span class=content>
Static Position of Grid Container Children</span></a></ul><li><a href=#grid-definition><span class=secno>5</span> <span class=content>
The Explicit Grid</span></a><ul class=toc><li><a href=#track-sizing><span class=secno>5.1</span> <span class=content>
Track Sizing: the <span class=property data-link-type=propdesc title=grid-template-rows>grid-template-rows</span> and <span class=property data-link-type=propdesc title=grid-template-columns>grid-template-columns</span> properties</span></a><ul class=toc><li><a href=#named-lines><span class=secno>5.1.1</span> <span class=content>
Named Grid Lines: the ''(<span class=production data-link-type=type title="<custom-ident>"><custom-ident></span>*)'' syntax</span></a><li><a href=#repeat-notation><span class=secno>5.1.2</span> <span class=content>
Repeating Rows and Columns: the <span class=css data-link-type=maybe title=repeat()>repeat()</span> notation</span></a><li><a href=#fr-unit><span class=secno>5.1.3</span> <span class=content>
Flexible Lengths: the <span class=css>fr</span> unit</span></a><li><a href=#subgrids><span class=secno>5.1.4</span> <span class=content>
Subgrids: the <span class=css data-link-for=grid-template-rows data-link-type=maybe title=subgrid>subgrid</span> keyword</span></a><li><a href=#resolved-track-list><span class=secno>5.1.5</span> <span class=content>
Resolved Values</span></a></ul><li><a href=#grid-template-areas-property><span class=secno>5.2</span> <span class=content>
Named Areas: the <span class=property data-link-type=propdesc title=grid-template-areas>grid-template-areas</span> property</span></a><ul class=toc><li><a href=#implicit-named-lines><span class=secno>5.2.1</span> <span class=content>
Implicit Named Lines</span></a><li><a href=#implicit-named-areas><span class=secno>5.2.2</span> <span class=content>
Implicit Named Areas</span></a></ul><li><a href=#explicit-grid-shorthand><span class=secno>5.3</span> <span class=content>
Explicit Grid Shorthand: the <span class=property data-link-type=propdesc title=grid-template>grid-template</span> property</span></a></ul><li><a href=#implicit-grids><span class=secno>6</span> <span class=content>
The Implicit Grid</span></a><ul class=toc><li><a href=#auto-tracks><span class=secno>6.1</span> <span class=content>
Sizing Auto-generated Rows and Columns: the <span class=property data-link-type=propdesc title=grid-auto-rows>grid-auto-rows</span> and <span class=property data-link-type=propdesc title=grid-auto-columns>grid-auto-columns</span> properties</span></a><li><a href=#grid-auto-flow-property><span class=secno>6.2</span> <span class=content>
<span data-dfn-type=dfn data-noexport="" title="auto-placement|automatic placement">Automatic Placement</span>: the <span class=property data-link-type=propdesc title=grid-auto-flow>grid-auto-flow</span> property</span></a></ul><li><a href=#grid-shorthand><span class=secno>7</span> <span class=content>
Grid Definition Shorthand: the <span class=property data-link-type=propdesc title=grid>grid</span> property</span></a><li><a href=#placement><span class=secno>8</span> <span class=content>
Placing Grid Items</span></a><ul class=toc><li><a href=#common-uses><span class=secno>8.1</span> <span class=content>
Common Patterns for Grid Placement</span></a><ul class=toc><li><a href=#common-uses-named-areas><span class=secno>8.1.1</span> <span class=content>
Named Areas</span></a><li><a href=#common-uses-numeric><span class=secno>8.1.2</span> <span class=content>
Numeric Indexes and Spans</span></a><li><a href=#common-uses-named-lines><span class=secno>8.1.3</span> <span class=content>
Named Lines and Spans</span></a><li><a href=#common-uses-auto-placement><span class=secno>8.1.4</span> <span class=content>
Auto Placement</span></a><li><a href=#common-uses-auto-sizing><span class=secno>8.1.5</span> <span class=content>
Auto Sizing Subgrids</span></a></ul><li><a href=#line-placement><span class=secno>8.2</span> <span class=content>
Line-based Placement: the <span class=property data-link-type=propdesc title=grid-row-start>grid-row-start</span>, <span class=property data-link-type=propdesc title=grid-column-start>grid-column-start</span>, <span class=property data-link-type=propdesc title=grid-row-end>grid-row-end</span>, and <span class=property data-link-type=propdesc title=grid-column-end>grid-column-end</span> properties</span></a><ul class=toc><li><a href=#grid-placement-errors><span class=secno>8.2.1</span> <span class=content>
Grid Placement Conflict Handling</span></a></ul><li><a href=#placement-shorthands><span class=secno>8.3</span> <span class=content>
Placement Shorthands: the <span class=property data-link-type=propdesc title=grid-column>grid-column</span>, <span class=property data-link-type=propdesc title=grid-row>grid-row</span>, and <span class=property data-link-type=propdesc title=grid-area>grid-area</span> properties</span></a><li><a href=#abspos-items><span class=secno>8.4</span> <span class=content>
Absolutely-positioned Grid Items</span></a><li><a href=#auto-placement-algo><span class=secno>8.5</span> <span class=content>
Grid Item Placement Algorithm</span></a></ul><li><a href=#alignment><span class=secno>9</span> <span class=content>
Alignment</span></a><ul class=toc><li><a href=#auto-margins><span class=secno>9.1</span> <span class=content>
Aligning with <span data-link-for=margin data-link-type=value title=auto>auto</span> margins</span></a><li><a href=#row-align><span class=secno>9.2</span> <span class=content>
Row-axis Alignment: the <span class=property data-link-type=propdesc title=justify-self>justify-self</span> and <span class=property data-link-type=propdesc title=justify-items>justify-items</span> properties</span></a><li><a href=#column-align><span class=secno>9.3</span> <span class=content>
Column-axis Alignment: the <span class=property data-link-type=propdesc title=align-self>align-self</span> and <span class=property data-link-type=propdesc title=align-items>align-items</span> properties</span></a><li><a href=#grid-align><span class=secno>9.4</span> <span class=content>
Aligning the Grid: the <span class=property data-link-type=propdesc title=justify-content>justify-content</span> and <span class=property data-link-type=propdesc title=align-content>align-content</span> properties</span></a><li><a href=#z-order><span class=secno>9.5</span> <span class=content>
Z-axis Ordering: the <span class=property data-link-type=propdesc title=z-index>z-index</span> property</span></a><li><a href=#grid-baselines><span class=secno>9.6</span> <span class=content>
Grid Baselines</span></a></ul><li><a href=#layout-algorithm><span class=secno>10</span> <span class=content>
Track Sizing Algorithm</span></a><ul class=toc><li><a href=#algo-terms><span class=secno>10.1</span> <span class=content>
Definition of Terms for use in Calculating Grid Track Sizes</span></a><li><a href=#algo-overview><span class=secno>10.2</span> <span class=content>
Overall Sizing Algorithm</span></a><li><a href=#algo-init><span class=secno>10.3</span> <span class=content>
Initialize Track Sizes</span></a><li><a href=#algo-content><span class=secno>10.4</span> <span class=content>
Resolve Content-Based Track Sizing Functions</span></a><li><a href=#algo-grow-tracks><span class=secno>10.5</span> <span class=content>
Grow All Tracks To Their Max</span></a><li><a href=#algo-flex-tracks><span class=secno>10.6</span> <span class=content>
Process Flexible Tracks</span></a><ul class=toc><li><a href=#algo-find-fr-size><span class=secno>10.6.1</span> <span class=content>
Find the Size of an <span class=css>fr</span></span></a></ul></ul><li><a href=#pagination><span class=secno>11</span> <span class=content>
Fragmenting Grid Layout</span></a><ul class=toc><li><a href=#fragmentation-alg><span class=secno>11.1</span> <span class=content>
Sample Fragmentation Algorithm</span></a></ul><li><a href=#acks><span class=secno></span> <span class=content>
Acknowledgements</span></a><li><a href=#changes><span class=secno></span> <span class=content>
Changes</span></a><li><a href=#translated-algo><span class=secno></span> <span class=content>
Appendix A: Translated Layout Algorithm</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=#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=#index><span class=secno></span> <span class=content>Index</span></a><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=intro><span class=secno>1. </span><span class=content>
Introduction and Overview</span><a class=self-link href=#intro></a></h2>
<p>Grid layout contains features targeted at web application authors.
The grid can be used to achieve many different layouts.
It excels at dividing up space for major regions of an application,
or defining the relationship in terms of size, position, and layer
between parts of a control built from HTML primitives.</p>
<p>Like tables,
grid layout enables an author to align elements into columns and rows,
but unlike tables,
grid layout doesn’t have content structure,
and thus enables a wide variety of layouts not possible with tables.
For example, the children of a grid container can position themselves
such that they overlap and layer similar to positioned elements.</p>
<p>In addition, the absence of content structure in grid layout helps to manage changes to layout
by using fluid and source order independent layout techniques.
By combining media queries with the CSS properties that control layout of the grid container and its children,
authors can adapt their layout to changes in device form factors, orientation, and available space,
without needing to alter the semantic nature of their content.</p>
<h3 class="heading settled" data-level=1.1 id=background><span class=secno>1.1. </span><span class=content>
Background and Motivation</span><a class=self-link href=#background></a></h3>
<figure class=sidefigure>
<img alt="Image: Application layout example requiring horizontal and vertical alignment." class=figure src=images/basic-form.png>
<figcaption>Application layout example requiring horizontal and vertical alignment.</figcaption>
</figure>
<p>As websites evolved from simple documents into complex, interactive applications,
tools for document layout, e.g. floats,
were not necessarily well suited for application l
DB4
ayout.
By using a combination of tables, JavaScript, or careful measurements on floated elements,
authors discovered workarounds to achieve desired layouts.
Layouts that adapted to the available space were often brittle
and resulted in counter-intuitive behavior as space became constrained.
As an alternative, authors of many web applications opted for a fixed layout
that cannot take advantage of changes in the available rendering space on a screen.</p>
<p>The capabilities of grid layout address these problems.
It provides a mechanism for authors to divide available space for layout into columns and rows
using a set of predictable sizing behaviors.
Authors can then precisely position and size the building block elements of their application
by into <a data-link-type=dfn href=#grid-area>grid areas</a&g
9F46
t; defined by these columns and rows.
Figure 1 illustrates a basic layout which can be achieved with grid layout.</p>
<h3 class="heading settled" data-level=1.2 id=adapting-to-available-space><span class=secno>1.2. </span><span class=content>
Adapting Layouts to Available Space</span><a class=self-link href=#adapting-to-available-space></a></h3>
<figure class=sidefigure>
<img alt="Image: Five grid items arranged according to content size and available space." src=images/game-smaller.png>
<figcaption>Five grid items arranged according to content size and available space.</figcaption>
</figure>
<figure class=sidefigure>
<img alt="Image: Growth in the grid due to an increase in available space." src=images/game-larger.png>
<figcaption>Growth in the grid due to an increase in available space.</figcaption>
</figure>
<p>Grid layout can be used to intelligently reflow elements within a webpage.
Figure 2 represents a game with five major areas in the layout:
the game title, stats area, game board, score area, and control area.
The author’s intent is to divide the space for the game such that:</p>
<ul>
<li>
The stats area always appears immediately under the game title.
<li>
The game board appears to the right of the stats and title.
<li>
The top of the game title and the game board should always align.
<li>
The bottom of the game board and the stats area align when the game has reached its minimum height,
but otherwise the game board will stretch to take advantage of all the screen real-estate available to it.
<li>
The score area should align into the column created by the game and stats area,
while the controls are centered under the board.
</ul>
<p>As an alternative to using script to control the absolute position, width, and height of all elements,
the author can use grid layout,
as shown in Figure 3.
The following example shows how an author might achieve all the sizing, placement, and alignment rules declaratively.</p>
<p>Note that there are multiple ways to specify the structure of the grid
and to position and size <a data-link-type=dfn href=#grid-item>grid items</a>,
each optimized for different scenarios.
This example illustrates one that an author may use to define the position and space for each <a data-link-type=dfn href=#grid-item>grid item</a>
using the <a class=property data-link-type=propdesc href=#propdef-grid-template-rows>grid-template-rows</a> and <a class=property data-link-type=propdesc href=#propdef-grid-template-columns>grid-template-columns</a> properties on the <a data-link-type=dfn href=#grid-container>grid container</a>,
and the <a class=property data-link-type=propdesc href=#propdef-grid-row>grid-row</a> and <a class=property data-link-type=propdesc href=#propdef-grid-column>grid-column</a> properties on each <a data-link-type=dfn href=#grid-item>grid item</a>.</p>
<div class=example>
<pre class=lang-css>#grid {
display: grid;
/* Two columns: the first sized to content, the second receives
* the remaining space, but is never smaller than the minimum
* size of the board or the game controls, which occupy this
* column. */
grid-template-columns: auto minmax(min-content, 1fr);
/* Three rows: the first and last sized to content, the middle
* row receives the remaining space, but is never smaller than
* the minimum height of the board or stats areas. */
grid-template-rows: auto minmax(min-content, 1fr) auto
}
/* Each part of the game is positioned between grid lines by
* referencing the starting grid line and then specifying, if more
* than one, the number of rows or columns spanned to determine
* the ending grid line, which establishes bounds for the part. */
#title { grid-column: 1; grid-row: 1 }
#score { grid-column: 1; grid-row: 3 }
#stats { grid-column: 1; grid-row: 2; justify-self: start }
#board { grid-column: 2; grid-row: 1 / span 2; }
#controls { grid-column: 2; grid-row: 3; align-self: center }
</pre>
<pre class=lang-markup><div id="grid">
<div id="title">Game Title</div>
<div id="score">Score</div>
<div id="stats">Stats</div>
<div id="board">Board</div>
<div id="controls">Controls</div>
</div>
</pre>
</div>
<h3 class="heading settled" data-level=1.3 id=source-independence><span class=secno>1.3. </span><span class=content>
Source-Order Independence</span><a class=self-link href=#source-independence></a></h3>
<figure class=sidefigure>
<img alt="Image: An arrangement suitable for portrait orientation." src=images/game-portrait.png>
<figcaption>An arrangement suitable for <span class=css>portrait</span> orientation.</figcaption>
</figure>
<figure class=sidefigure>
<img alt="Image: An arrangement suitable for landscape orientation." src=images/game-landscape.png>
<figcaption>An arrangement suitable for <span class=css>landscape</span> orientation.</figcaption>
</figure>
<p>Continuing the prior example,
the author also wants the game to adapt to the space available on traditional computer monitors, handheld devices, or tablet computers.