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diff --git a/files/fr/web/accessibility/understanding_wcag/index.html b/files/fr/web/accessibility/understanding_wcag/index.html new file mode 100644 index 0000000000..5e99ef795d --- /dev/null +++ b/files/fr/web/accessibility/understanding_wcag/index.html @@ -0,0 +1,58 @@ +--- +title: Understanding the Web Content Accessibility Guidelines +slug: Web/Accessibility/Understanding_WCAG +tags: + - TopicStub + - WCAG + - Web Content Accessibility Guidelines +translation_of: Web/Accessibility/Understanding_WCAG +--- +<p class="summary">Cet ensemble d'articles fournit des explications rapides pour vous aider à comprendre les étapes à suivre pour vous conformer aux recommandations décrites dans les Directives d'accessibilité du contenu Web 2.0 ou 2.1 du W3C (ou simplement WCAG, aux fins de cet article).</p> + +<p>Les WCAG 2.0 et 2.1 fournissent un ensemble détaillé de lignes directrices pour rendre le contenu Web plus accessible aux personnes ayant une grande variété de handicaps. Il est complet mais incroyablement détaillé et assez difficile à comprendre rapidement. Pour cette raison, nous avons résumé les étapes pratiques que vous devez suivre pour satisfaire les différentes recommandations, avec d'autres liens vers plus de détails si nécessaire.</p> + +<h2 id="Les_quatre_principes">Les quatre principes</h2> + +<p>Les WCAG sont globalement divisés en quatre principes — éléments majeurs que le contenu Web <strong>doit être</strong> pour être considéré comme accessible (voir <a href="https://www.w3.org/TR/UNDERSTANDING-WCAG20/intro.html#introduction-fourprincs-head">Comprendre les Quatre Principes d'Accessibilité </a>pour les définitons des WCAG).</p> + +<p>Chacun des liens ci-dessous vous mènera à des pages qui développent davantage ces domaines, vous donnant des conseils pratiques sur la façon de rédiger votre contenu Web afin qu'il soit conforme aux critères de succès décrits dans chacune des directives WCAG 2.0 et 2.1 qui se subdivisent davantage en chaque principe.</p> + +<ul> + <li><a href="https://developer.mozilla.org/en-US/docs/user:chrisdavidmills/Understanding_WCAG/Perceivable">Perceptile:</a> Les utilisateurs doivent pouvoir le percevoir d'une manière ou d'une autre, en utilisant un ou plusieurs de leurs sens.</li> + <li><a href="/en-US/docs/user:chrisdavidmills/Understanding_WCAG/Operable">Opérable</a>: Les utilisateurs doivent pouvoir contrôler les éléments de l'interface utilisateur (par exemple, les boutons doivent être cliquables d'une manière ou d'une autre - souris, clavier, commande vocale, etc.).</li> + <li><a href="/en-US/docs/user:chrisdavidmills/Understanding_WCAG/Understandable">Compréhensible</a>: Le contenu doit être compréhensible pour ses utilisateurs.</li> + <li><a href="/en-US/docs/user:chrisdavidmills/Understanding_WCAG/Robust">Robuste</a>: Le contenu doit être développé à l'aide de normes Web bien adoptées qui fonctionneront sur différents navigateurs, maintenant et à l'avenir.</li> +</ul> + +<h2 id="Dois-je_utiliser_WCAG_2.0_ou_2.1">Dois-je utiliser WCAG 2.0 ou 2.1?</h2> + +<p>WCAG 2.1 est la norme d'accessibilité la plus récente et la plus pertinente. Utilisez WCAG 2.1 pour aider plus de personnes handicapées et réduire le risque juridique futur pour les propriétaires de sites Web. Ciblez d'abord WCAG 2.0 lors de l'allocation des ressources. Passez ensuite à WCAG 2.1. </p> + +<h3 id="Quest-ce_que_WCAG_2.1">Qu'est-ce que WCAG 2.1?</h3> + +<p>WCAG 2.1 a été publié en tant que recommandation officielle le 5 juin 2018. L'Union européenne (UE) a adopté WCAG 2.1 comme norme d'accessibilité numérique en septembre 2018. Le W3C a publié un communiqué de presse <a href="https://www.w3.org/blog/2018/09/wcag-2-1-adoption-in-europe/">WCAG 2.1 Adoption en Europe</a>. </p> + +<p>WCAG 2.1 comprend:</p> + +<ul> + <li>tous les WCAG 2.0 (textuellement, mot-à-mot)</li> + <li>17 nouveaux critères de succès aux niveaux A / AA / AAA répondant principalement aux besoins des utilisateurs dans ces domaines: + <ul> + <li>Accessibilité mobile</li> + <li>Vision faible</li> + <li>Cognitive</li> + </ul> + </li> + <li>En savoir plus sur WCAG 2.1: + <ul> + <li>Deque: <a href="https://www.deque.com/blog/wcag-2-1-what-is-next-for-accessibility-guidelines/">WCAG 2.1: Quelle est la suite des directives d'accessibilité</a></li> + <li>TPG: <a href="https://developer.paciellogroup.com/blog/2018/06/web-content-accessibility-guidelines-wcag-2-1/">Directives pour l'Accessibilité des Contenus Web (WCAG) 2.1</a></li> + </ul> + </li> +</ul> + +<h2 id="Statut_juridique">Statut juridique</h2> + +<p>Ce guide est destiné à fournir des informations pratiques pour vous aider à créer de meilleurs sites Web plus accessibles. Cependant, nous ne sommes pas des avocats et rien de tout cela ne constitue un avis juridique. Si vous êtes préoccupé par les implications juridiques de l'accessibilité du Web, nous vous recommandons de vérifier la législation spécifique régissant l'accessibilité du Web / des ressources publiques dans votre pays ou région, et de demander l'avis d'un avocat qualifié.</p> + +<p><a href="/en-US/docs/Learn/Accessibility/What_is_accessibility">Qu'est ce que l'accessibilité?</a> et particularité, <a href="/en-US/docs/Learn/Accessibility/What_is_accessibility#Accessibility_guidelines_and_the_law">les directives d'Accessibility et la section sur la loi</a> fournissent des informations complémentaires.</p> diff --git a/files/fr/web/accessibility/understanding_wcag/perceivable/contraste_de_la_couleur/index.html b/files/fr/web/accessibility/understanding_wcag/perceivable/contraste_de_la_couleur/index.html new file mode 100644 index 0000000000..497a2675f7 --- /dev/null +++ b/files/fr/web/accessibility/understanding_wcag/perceivable/contraste_de_la_couleur/index.html @@ -0,0 +1,162 @@ +--- +title: Contraste de la couleur +slug: Web/Accessibility/Understanding_WCAG/Perceivable/Contraste_de_la_couleur +tags: + - Accessibilité + - WCAG + - contraste +translation_of: Web/Accessibility/Understanding_WCAG/Perceivable/Color_contrast +--- +<p>Le <a href="https://www.w3.org/TR/WCAG21/#dfn-contrast-ratio">contraste de la couleur</a> entre l'arrière-plan et le contenu de premier-plan (qui est en général du texte) doit être assez prononcé pour assurer la lisibilité.</p> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Lors de la conception d'interfaces lisibles pour différentes capacités de vision, les directives WCAG recommandent les rapports de contraste suivants:</span></span></p> + +<table class="standard-table"> + <thead> + <tr> + <th scope="col">Type de contenu</th> + <th scope="col">Ratio minimum (Note AA)</th> + <th scope="col">Ratio amélioré (Note AAA)</th> + </tr> + </thead> + <tbody> + <tr> + <td>Corps</td> + <td>4.5 : 1</td> + <td>7 : 1</td> + </tr> + <tr> + <td>Texte grande échelle (120-150% plus large que le corps)</td> + <td>3 : 1</td> + <td>4.5 : 1</td> + </tr> + <tr> + <td><span class="tlid-translation translation" lang="fr"><span title="">Composants d'interface utilisateur actifs et objets graphiques tels que des icônes et des graphiques</span></span></td> + <td>3 : 1</td> + <td>Non défini</td> + </tr> + </tbody> +</table> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Ces ratios ne s'appliquent pas au texte "accessoire", comme les contrôles inactifs, les logotypes ou le texte purement décoratif.</span></span></p> + +<p>Voir la section {{anch("Solution")}} ci-dessous pour plus d'informations.</p> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Un bon contraste des couleurs sur votre site profite à tous vos utilisateurs, mais celà est particulièrement intéressant pour les utilisateurs souffrant de certains types de daltonisme et d'autres particularités similaires, qui rencontrent un faible contraste et ont du mal à faire la différence entre des couleurs proches.</span> <span title="">En effet, ces utilisateurs ne voient pas les zones claires et sombres aussi facilement que ceux sans ces particularités et ont donc du mal à voir les bords, les bordures et d'autres détails.</span></span></p> + +<p><span class="tlid-translation translation" lang="fr"><span title="">C'est bien d'avoir un design cool sur votre site, mais le design ne vaut rien si vos utilisateurs ne peuvent pas lire votre contenu.</span></span></p> + +<h2 id="Exemples">Exemples</h2> + +<p>Jetons un coup d<span class="tlid-translation translation" lang="fr"><span title="">'œil à du</span></span> code HTML et CSS assez simple:</p> + +<pre class="brush: html"><div class="bon">Bon contraste</div> +<div class="mauvais">Mauvais contraste</div></pre> + +<pre class="brush: css">div { + /* Styles généraux de div ici */ +} + +.bon { + background-color: #fae6fa; +} + +.mauvais { + background-color: #400064; +}</pre> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Les deux textes ont leur couleur noire par défaut.</span></span> La "bonne" <code><div></code> a un fond violet clair, ce qui rend le texte facile à lire:</p> + +<div class="hidden"> +<h4 id="exemple1">exemple1</h4> + +<pre class="brush: html"> <div class="bon"> + Bon contraste + </div></pre> + +<pre class="brush: css">div { + font-family: sans-serif; + text-align: center; + font-size: 2rem; + font-weight: bold; + width: 250px; + padding: 30px; + border-radius: 20px; + box-shadow: 1px 1px 1px black; +} + +.bon { + background-color: #fae6fa; +}</pre> +</div> + +<p>{{EmbedLiveSample('exemple1', '100%', '100')}}</p> + +<p>La "mauvaise" <code><div></code>, en revanche, a un fond violet très foncé, ce qui rend le texte beaucoup plus difficile à lire:</p> + +<div class="hidden"> +<h4 id="exemple2">exemple2</h4> + +<pre class="brush: html"> <div class="mauvais"> + Mauvais contraste + </div></pre> + +<pre class="brush: css">div { + font-family: sans-serif; + text-align: center; + font-size: 2rem; + font-weight: bold; + width: 250px; + padding: 30px; + border-radius: 20px; + box-shadow: 1px 1px 1px black; +} + +.mauvais { + background-color: #400064; +}</pre> +</div> + +<p>{{EmbedLiveSample('exemple2', '100%', '100')}}</p> + +<dl> +</dl> + +<h2 id="Solution">Solution</h2> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Lorsque vous choisissez un jeu de couleurs pour votre site Web, choisissez des couleurs de premier plan et d'arrière-plan qui offrent un bon contraste.</span> <span title="">Faites en sorte que le contraste des couleurs soit aussi bon que possible dans vos contraintes de conception - optez idéalement pour la note AAA (voir paragraphe 1.4.6 ci-dessous), mais répondez au moins à la note AA (voir paragraphe 1.4.3 ci-dessous).</span></span></p> + +<p><span class="tlid-translation translation" lang="fr"><span title="">Si vous incluez du contenu non textuel tel qu'une vidéo ou une animation, vous devrez suivre le paragraphe 1.4.11 (encore une fois, voir ci-dessous).</span></span></p> + +<p>Pour vérifier votre contraste lorsque vous effectuez un choix de couleurs, vous pouvez utiliser le <a class="external external-icon" href="http://webaim.org/resources/contrastchecker/" rel="noopener">Vérificateur de Contraste des Couleurs</a> de WebAIM.</p> + +<p>Vous pouvez également vérifier le contraste des couleurs directement via les outils de développement de Firefox — consultez notre guide de l'<a href="https://developer.mozilla.org/fr/docs/Outils/Inspecteur_accessibilite">Inspecteur de l'accessibilité</a>, et en particulier la section <a href="https://developer.mozilla.org/fr/docs/Outils/Inspecteur_accessibilite#S%C3%A9lecteur_d'accessibilit%C3%A9">Vérifier les problèmes d'accessibilité</a>. Essayez de les utiliser sur les exemples dans la section de description.</p> + +<h2 id="Critères_de_réussite_associés_aux_WCAG"><span class="tlid-translation translation" lang="fr"><span title="">Critères de réussite associés aux WCAG</span></span></h2> + +<dl> + <dt><a href="https://www.w3.org/TR/WCAG21/#contrast-minimum">1.4.3 Contraste minimum (AA)</a></dt> + <dd><span class="tlid-translation translation" lang="fr"><span title="">Le contraste des couleurs entre le contenu d'arrière-plan et de premier plan doit être au minimum pour garantir la lisibilité:</span></span> + <ul> + <li>Le texte et son arrière-plan doivent avoir un ratio de contraste d'au moins 4.5:1.</li> + <li>Le texte d'en-tête (ou juste "plus grand") doit avoir un ratio d'au moins 3:1. Le texte "plus grand" est défini comme au moins 18pt, ou 14pt en gras.</li> + </ul> + </dd> + <dt><a href="https://www.w3.org/TR/WCAG21/#contrast-enhanced">1.4.6 Contraste amélioré (AAA)</a></dt> + <dd><span class="tlid-translation translation" lang="fr"><span title="">Cela suit et s'appuie sur le critère 1.4.3.</span></span> + <ul> + <li>Le texte et son arrière-plan doivent avoir un ratio de contraste d'au moins 7:1.</li> + <li>Le texte d'en-tête (ou juste "plus grand") doit avoir un ratio d'au moins 4.5:1.</li> + </ul> + </dd> + <dt><a href="https://www.w3.org/TR/WCAG21/#non-text-contrast">1.4.11 Contraste non textuel (AA)</a> (ajouté en 2.1)</dt> + <dd><span class="tlid-translation translation" lang="fr"><span title="">Il doit y avoir un ratio de contraste de couleur minimum de 3 à 1 pour les composants de l'interface utilisateur et les objets graphiques.</span></span></dd> +</dl> + +<h2 id="Voir_aussi">Voir aussi</h2> + +<ul> + <li><a href="https://developer.mozilla.org/fr/docs/Apprendre/a11y/CSS_and_JavaScript#Couleur_et_contraste_de_couleur">Couleur et contraste de couleur</a></li> + <li><a href="https://wiki.developer.mozilla.org/fr/docs/Web/Guide/HTML/Formulaires/Comment_structurer_un_formulaire_HTML#%C3%89tiquettes_multiples">Étiquettes multiples</a></li> + <li><a href="https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast.html">Comprendre le contraste non textuel</a></li> +</ul> diff --git a/files/fr/web/accessibility/understanding_wcag/perceivable/index.html b/files/fr/web/accessibility/understanding_wcag/perceivable/index.html new file mode 100644 index 0000000000..e8059d8fca --- /dev/null +++ b/files/fr/web/accessibility/understanding_wcag/perceivable/index.html @@ -0,0 +1,359 @@ +--- +title: Perceivable +slug: Web/Accessibility/Understanding_WCAG/Perceivable +tags: + - Accessibility + - NeedsTranslation + - Principle 1 + - TopicStub + - WCAG + - Web Content Accessibility Guidelines + - contrast + - different presentation + - text alternatives + - time-based media +translation_of: Web/Accessibility/Understanding_WCAG/Perceivable +--- +<p class="summary">This article provides practical advice on how to write your web content so that it conforms to the success criteria outlined in the <strong>Perceivable</strong> principle of the Web Content Accessibility Guidelines (WCAG) 2.0 and 2.1. Perceivable states that users must be able to perceive it in some way, using one or more of their senses.</p> + +<div class="note"> +<p><strong>Note</strong>: To read the W3C definitions for Perceivable and its guidelines and success criteria, see <a href="https://www.w3.org/TR/WCAG21/#perceivable">Principle 1: Perceivable - Information and user interface components must be presentable to users in ways they can perceive.</a></p> +</div> + +<h2 id="Guideline_1.1_—_Providing_text_alternatives_for_non-text_content">Guideline 1.1 — Providing text alternatives for non-text content</h2> + +<p>The key here is that text can be converted to other forms people with disabilities can use, so for example spoken by a screenreader, zoomed in, or represented on a braille display. Non-text content refers to multimedia such as images, audio, and video.</p> + +<table class="standard-table"> + <thead> + <tr> + <th scope="col">Success criteria</th> + <th scope="col">How to conform to the criteria</th> + <th scope="col">Practical resource</th> + </tr> + </thead> + <tbody> + <tr> + <td colspan="1" rowspan="5">1.1.1 Provide text equivalents (A)</td> + <td>All images that convey meaningful content should be given suitable alternative text.</td> + <td><a href="/en-US/docs/Learn/Accessibility/HTML#Text_alternatives">Text alternatives.</a></td> + </tr> + <tr> + <td>Complex images or charts should have an accessible alternative provided, either on the same page or linked to. Use a regular link rather than the <code>longdesc</code> attribute.</td> + <td> + <p>A text description may work, or an accessible data table (see <a href="/en-US/docs/Learn/HTML/Tables/Advanced">HTML table advanced features and accessibility</a>). Also see <a href="/en-US/docs/Learn/Accessibility/HTML#Other_text_alternative_mechanisms">Other text alternative mechanisms</a> for the argument against <code>longdesc</code>.</p> + </td> + </tr> + <tr> + <td>Multimedia content (e.g. audio or video) should at least have a descriptive identification available (e.g. a caption or similar).</td> + <td> + <p>See <a href="/en-US/docs/Learn/Accessibility/HTML#Text_alternatives">Text alternatives</a> for static caption options, and <a href="/en-US/docs/Learn/Accessibility/Multimedia#Audio_transcripts">Audio transcripts</a>, <a href="/en-US/docs/Learn/Accessibility/Multimedia#Video_text_tracks">Video text tracks</a>, and <a href="/en-US/docs/Learn/Accessibility/Multimedia#Other_multimedia_content">Other multimedia content</a> for other alternatives.</p> + </td> + </tr> + <tr> + <td>UI Controls such as form elements and buttons should have text labels that describe their purpose.</td> + <td>Buttons are simple — you should make sure the button text describes the function of the button (e.g. <code><button>Upload image</button></code>). For further information on other UI controls, see <a href="/en-US/docs/Learn/Accessibility/HTML#UI_controls">UI controls</a>.</td> + </tr> + <tr> + <td>Implement decorative (non-content) images, video, etc., in a way that is invisible to assistive technology, so it doesn't confuse users.</td> + <td> + <p>Decorative images should be implemented using CSS background images (see <a href="/en-US/docs/Learn/CSS/Styling_boxes/Backgrounds">Backgrounds</a>). If you have to include an image via an {{htmlelement("img")}} element, give it a blank alt (<code>alt=""</code>), otherwise screenreaders may try to read out the filepath, etc.</p> + + <p>If you are including background video or audio that autoplays, make it as unobtrusive as possible. Don't make it look/sound like content, and provide a control to turn it off. Ideally, don't include it at all.</p> + </td> + </tr> + </tbody> +</table> + +<div class="note"> +<p><strong>Note</strong>: Also see the <a href="https://www.w3.org/TR/WCAG21/#text-alternatives">WCAG description for Guideline 1.1: Text alternatives</a>.</p> +</div> + +<h2 id="Guideline_1.2_—_Providing_text_alternatives_for_time-based_media">Guideline 1.2 — Providing text alternatives for time-based media</h2> + +<p>Time-based media refers to multimedia with a duration, i.e. audio and video. Also note that if the audio/video serves as an alternative to existing text content, you don't need to provide another text alternative.</p> + +<table class="standard-table"> + <thead> + <tr> + <th scope="col">Success criteria</th> + <th scope="col">How to conform to the criteria</th> + <th scope="col">Practical resource</th> + </tr> + <tr> + <td colspan="1" rowspan="1">1.2.1 Provide alternatives for pre-recorded audio-only and video-only content (A)</td> + <td>A transcript should be provided for prerecorded audio-only media, and a transcript or audio description should be provided for prerecorded video-only media (i.e. silent video).</td> + <td>See <a href="/en-US/docs/Learn/Accessibility/Multimedia#Audio_transcripts">Audio transcripts</a> for transcript information. No audio description tutorial available as yet.</td> + </tr> + <tr> + <td colspan="1">1.2.2 Provide captions for web-based video (A)</td> + <td>You should provide captions for video presented on the web, e.g. HTML5 video. This is for the benefit of people who can't hear the audio part of the video.</td> + <td>See <a href="/en-US/docs/Learn/Accessibility/Multimedia#Video_text_tracks">Video text tracks</a> for HTML5 video captions, and <a href="/en-US/docs/Learn/Accessibility/Multimedia#Other_multimedia_content">Other multimedia content</a> for other technologies. See also <a href="https://support.google.com/youtube/answer/2734796?hl=en">Add your own subtitles & closed captions</a> (YouTube).</td> + </tr> + <tr> + <td colspan="1">1.2.3 Provide text transcript or audio description for web-based video (A)</td> + <td>You should provide text transcripts or audio descriptions for video presented on the web, e.g. HTML5 video. This is for the benefit of people who can't see the visual part of the video, and don't get the full content from the audio alone.</td> + <td>See <a href="/en-US/docs/Learn/Accessibility/Multimedia#Audio_transcripts">Audio transcripts</a> for transcript information. No audio description tutorial available as yet.</td> + </tr> + <tr> + <td colspan="1">1.2.4 Provide captions for live audio (AA)</td> + <td>You should provide synchronized captions for all live multimedia that contains audio (e.g. video conferences, live audio broadcasts.)</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.2.5 Provide audio descriptions for prerecorded video (AA)</td> + <td>Audio descriptions should be provided for prerecorded video, but only where the existing audio does not convey the full meaning expressed by the video.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.2.6 Provide sign language equivalent to prerecorded audio (AAA)</td> + <td>An equivalent sign language video should be provided for any prerecorded content containing audio.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.2.7 Provide extended video with audio descriptions (AAA)</td> + <td>Where audio descriptions cannot be provided (see 1.2.5) due to video timing issues (e.g. there are no suitable pauses in the content in which to insert the audio descriptions), an alternative version of the video should be provided that includes inserted pauses (and audio descriptions).</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.2.8 Provide an alternative for prerecorded media (AAA)</td> + <td>For all content that features video, a descriptive text transcript should be provided, for example a script of the movie you are watching. This is for the benefit of hearing impaired viewers who cannot hear the content.</td> + <td>See <a href="/en-US/docs/Learn/Accessibility/Multimedia#Audio_transcripts">Audio transcripts</a> for transcript information.</td> + </tr> + <tr> + <td colspan="1">1.2.9 Provide a transcript for live audio (AAA)</td> + <td>For any live audio content being broadcast, a descriptive text should be provided, for example a script of the play or musical you are listening to. This is for the benefit of hearing impaired viewers who cannot hear the content.</td> + <td>See <a href="/en-US/docs/Learn/Accessibility/Multimedia#Audio_transcripts">Audio transcripts</a> for transcript information.</td> + </tr> + </thead> +</table> + +<div class="note"> +<p><strong>Note</strong>: Also see the <a href="https://www.w3.org/TR/WCAG21/#time-based-media">WCAG description for Guideline 1.2: Time-based Media: Provide alternatives for time-based media</a>.</p> +</div> + +<h2 id="Guideline_1.3_—_Create_content_that_can_be_presented_in_different_ways">Guideline 1.3 — Create content that can be presented in different ways</h2> + +<p>This guideline refers to the ability of content to be consumed by users in multiple ways, accomodating their differing needs.</p> + +<table class="standard-table"> + <tbody> + <tr> + <th scope="col">Success criteria</th> + <th scope="col">How to conform to the criteria</th> + <th scope="col">Practical resource</th> + </tr> + <tr> + <td colspan="1" rowspan="1">1.3.1 Info and relationships (A)</td> + <td> + <p>Any content structure — or visual relationship made between content — can also be determined programmatically, or be inferred from text description. The main situations in which this is relevant are:</p> + + <ul> + <li>Text labels and the form elements they describe are associated unambiguously using the {{htmlelement("label")}} element, which can be picked up by screenreaders, etc.</li> + <li>Image alt text — content images should have text available that clearly describes the image's contents, which can be programmatically associated with it (e.g. <code>alt</code> text), or otherwise is easy to associate (e.g. describes it and is sat right next to it). This should means that the full meaning can still be inferred even if you can't see the image.</li> + <li>Lists — if the order of list items is important, and ordered list should be used ({{htmlelement("ol")}}).</li> + </ul> + </td> + <td>The whole of + <p><a href="/en-US/docs/Learn/Accessibility/HTML">HTML: A good basis for accessibility</a> is packed with information about this, but you should particularly refer to <a href="/en-US/docs/Learn/Accessibility/HTML#Good_semantics">Good semantics</a>, <a href="/en-US/docs/Learn/Accessibility/HTML#UI_controls">UI controls</a>, and <a href="/en-US/docs/Learn/Accessibility/HTML#Text_alternatives">Text alternatives</a>.</p> + </td> + </tr> + <tr> + <td colspan="1">1.3.2 Meaningful content sequence (A)</td> + <td>A sensible, logical reading order should be easy to determine for any content, even if it is visually presented in an unusual way. The order should be made obvious by use of correct semantic elements (e.g. headings, paragraphs), with CSS being used to create any unusual layout styles, irrespective of the markup.</td> + <td>Again, refer to <a href="/en-US/docs/Learn/Accessibility/HTML">HTML: A good basis for accessibility</a>.</td> + </tr> + <tr> + <td colspan="1">1.3.3 Sensory characteristics (A)</td> + <td> + <p>Instructions for operating controls or understanding content do not rely on a single sense — this may prove inaccessible to people with a disability related to that sense, or a device that does not support that sense. So for example:</p> + + <ul> + <li>"Click the round button to continue" — The button should be clearly labelled so that it is obvious that it is the button you need to press. If there are multiple buttons, make sure there are all clearly labelled to distinguish their function.</li> + <li>"Listen to the audio instructions for guidance" — This is obviously problematic — audio will be inaccessible to those with heading impairments, whereas text can be read, but also spoken by a screenreader if required.</li> + <li>"Swipe from the right hand side of the screen to reveal the menu" — some users might not be able to swipe the screen, either due to disability or because their device does not support touch. An alternative should be provided, such as a keyboard shortcut or button that can be activated by keyboard or other means.</li> + </ul> + + <div class="note"> + <p><strong>Note</strong>: Conveying instructions solely by color is related, but covered in a different guideline — 1.4.1.</p> + </div> + </td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.3.4 Orientation (AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td>Content does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.</td> + <td> + <p><a href="https://www.w3.org/WAI/WCAG21/Understanding/orientation.html">Understanding Orientation</a> </p> + </td> + </tr> + <tr> + <td colspan="1">1.3.5 Identify Input Purpose (AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td> + <p> </p> + + <p>Follow the list of <a href="https://www.w3.org/TR/WCAG21/#input-purposes">53 input fields</a> to programmatically identify the purpose of a field. </p> + </td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/identify-input-purpose.html">Understanding Identify Input Purpose</a></td> + </tr> + <tr> + <td colspan="1">1.3.6 Identify Purpose (AAA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td>In content implemented using markup languages, the purpose of User Interface Components, icons, and regions can be programmatically determined.</td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/identify-purpose.html">Understanding Identify Purpose</a></td> + </tr> + </tbody> +</table> + +<div class="note"> +<p><strong>Note</strong>: Also see the WCAG description for <a href="https://www.w3.org/TR/WCAG21/#adaptable">Guideline 1.3: Adaptable: Create content that can be presented in different ways without losing information or structure.</a></p> +</div> + +<h2 id="Guideline_1.4_Make_it_easier_for_users_to_see_and_hear_content_including_separating_foreground_from_background">Guideline 1.4: Make it easier for users to see and hear content including separating foreground from background</h2> + +<p>This guideline relates to making sure core content is easy to discernable from backgrounds and other decoration. The classic example is color (both color contrast and use of color to convey instructions), but it applies in other situations too.</p> + +<table class="standard-table"> + <thead> + <tr> + <th scope="col">Success criteria</th> + <th scope="col">How to conform to the criteria</th> + <th scope="col">Practical resource</th> + </tr> + <tr> + <td colspan="1" rowspan="1">1.4.1 Use of color (A)</td> + <td> + <p>Color should not be solely relied upon to convey information — for example, in forms you should never mark required fields purely with a color (like red). Instead (or as well as), something like an asterisk with a label of "required" would be more appropriate.</p> + </td> + <td>See <a href="/en-US/docs/Learn/Accessibility/CSS_and_JavaScript#Color_and_color_contrast">Color and color contrast</a> and <a href="/en-US/docs/Learn/HTML/Forms/How_to_structure_an_HTML_form#Multiple_labels">Multiple labels</a>.</td> + </tr> + <tr> + <td colspan="1">1.4.2 Audio controls (A)</td> + <td>For any audio that plays for longer than three seconds, accessible controls should be provided to play and pause the audio/video, and mute/adjust volume.</td> + <td>Use native <code><button></code>s to provide accessible keyboard controls, as shown in <a href="/en-US/docs/Web/Apps/Fundamentals/Audio_and_video_delivery/Video_player_styling_basics">Video player syling basics</a>.</td> + </tr> + <tr> + <td colspan="1">1.4.3 Minimum contrast (AA)</td> + <td> + <p>The color contrast between background and foreground content should be at a minimum level to ensure legibility:</p> + + <ul> + <li>Text and its background should have a contrast ratio of at least 4.5.1.</li> + <li>Heading (or just larger) text should have a ratio of at least 3.1. Larger text is defined as at least 18pt, or 14pt bold.</li> + </ul> + </td> + <td>See <a href="/en-US/docs/Learn/Accessibility/CSS_and_JavaScript#Color_and_color_contrast">Color and color contrast</a>.</td> + </tr> + <tr> + <td colspan="1">1.4.4 Resize text (AA)</td> + <td>The page should be readable and usable when the text size is doubled. This means that designs should be responsive, so that when the text size is increased, the content is still accessible.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.4.5 Images of text (AA)</td> + <td>Images should NOT be used to present content where text would do the job. For example, if an image is mostly textual, it could be represented using text as well as images.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.4.6 Enhanced contrast (AAA)</td> + <td> + <p>This follows, and builds on, criterion 1.4.3.</p> + + <ul> + <li>Text and its background should have a contrast ratio of at least 7.1.</li> + <li>Heading (or just larger) text should have a ratio of at least 4.5.1. Larger text is defined as at least 18pt, or 14pt bold.</li> + </ul> + </td> + <td>See <a href="/en-US/docs/Learn/Accessibility/CSS_and_JavaScript#Color_and_color_contrast">Color and color contrast</a>.</td> + </tr> + <tr> + <td colspan="1">1.4.7 Low or no background audio (AAA)</td> + <td>Prerecorded audio recordings that primarily feature speech should have minimal background noise, so the content can be easily understood.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.4.8 Visual presentation (AAA)</td> + <td> + <p>For text content presentation, the following should be true:</p> + + <ul> + <li>Foreground and background colors should be user-selectable.</li> + <li>Text blocks should be no wider than 80 characters (or glyphs), for maximum readability.</li> + <li>Text should not be fully justified (e.g. <code>text-align: justify;</code>)</li> + <li>line height should be at least 1.5 times the text size within paragraphs (e.g. <code>line-height: 1.5;</code>), and at least 2.25 times the text size between paragraphs (e.g. <code>padding: 2.25rem;</code>)</li> + <li>When the text size is doubled, the content should not need to be scrolled.</li> + </ul> + </td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.4.9 Images of text (No Exception) (AAA)</td> + <td>Text should not be presented as part of an image unless it is purely decoration (i.e. it does not convey any content), or cannot be presented in any other way.</td> + <td> </td> + </tr> + <tr> + <td colspan="1">1.4.10 Reflow (AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td> + <ul> + <li>No horizontal scrolling for right-to-left languages (like English) or left-to-right languages (like Arabic) </li> + <li>No vertical scrolling for top-to-bottom languages (like Japanese)</li> + <li>Except for parts of the content which require two-dimensional layout for usage or meaning (like a large data table).</li> + </ul> + </td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/reflow.html">Understanding Reflow</a></td> + </tr> + <tr> + <td colspan="1">1.4.11 Non-Text Contrast(AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td>Minimum color contrast ratio of 3 to 1 for user interface components and graphical objects. </td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast.html">Understanding Non-Text Contrast</a></td> + </tr> + <tr> + <td colspan="1">1.4.12 Text Spacing (AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td> + <p>No loss of content or functionality occurs when the following styles are applied: </p> + + <ul> + <li>Line height (line spacing) to at least 1.5 times the font size;</li> + <li>Spacing following paragraphs to at least 2 times the font size;</li> + <li>Letter spacing (tracking) to at least 0.12 times the font size;</li> + <li>Word spacing to at least 0.16 times the font size.</li> + </ul> + </td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/text-spacing.html">Understanding Text Spacing</a></td> + </tr> + <tr> + <td colspan="1">1.4.13 Content on Hover or Focus (AA) <em><a href="https://www.w3.org/TR/WCAG21/#new-features-in-wcag-2-1">added in 2.1</a></em></td> + <td> + <p>Additional content appear and disappear in coordination with hover and keyboard focus, this success criterion specifies three conditions that must be met:</p> + + <ul> + <li>dismissable (can be closed/removed)</li> + <li>hoverable (the additional content does not disappear when the pointer is over it) </li> + <li>persistent (the additional content does not disappear without user action)</li> + </ul> + </td> + <td><a href="https://www.w3.org/WAI/WCAG21/Understanding/content-on-hover-or-focus.html">Understanding Content on Hover or Focus</a></td> + </tr> + </thead> +</table> + +<div class="note"> +<p><strong>Note</strong>: Also see the WCAG description for <a href="https://www.w3.org/TR/WCAG21/#distinguishable">Guideline 1.4: Distinguishable: Make it easier for users to see and hear content including separating foreground from background.</a><a href="https://www.w3.org/TR/WCAG21/#distinguishable">.</a></p> +</div> + +<p> </p> + +<h2 id="See_Also">See Also</h2> + +<ul> + <li><a href="en-US/docs/Web/Accessibility/Understanding_WCAG">WCAG</a> + + <ol> + <li>Perceivable</li> + <li><a href="/en-US/docs/Web/Accessibility/Understanding_WCAG/Operable">Operable</a></li> + <li><a href="/en-US/docs/Web/Accessibility/Understanding_WCAG/Understandable">Understandable</a></li> + <li><a href="/en-US/docs/Web/Accessibility/Understanding_WCAG/Robust">Robust</a></li> + </ol> + </li> +</ul> + +<p> </p> |