{"id":7418,"date":"2025-10-14T10:51:12","date_gmt":"2025-10-14T15:51:12","guid":{"rendered":"https:\/\/frontendmasters.com\/blog\/?p=7418"},"modified":"2025-10-14T10:51:14","modified_gmt":"2025-10-14T15:51:14","slug":"a11y-linting-html-with-css","status":"publish","type":"post","link":"https:\/\/frontendmasters.com\/blog\/a11y-linting-html-with-css\/","title":{"rendered":"A11Y Linting HTML with CSS"},"content":{"rendered":"\n<p>Will Mendes has <a href=\"https:\/\/gist.github.com\/willmendesneto\/4302de65ed6fa0e3661d3c0c08cf2a28\">a bit of CSS to highlight accessibility issues<\/a> on HTML elements. Things like missing <code>alt<\/code> text and labels that aren&#8217;t linked properly to inputs. If you want to try it out quick on a website, I wrapped it in a little injection JavaScript so you could paste it in the console wherever.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>Console Code<\/summary><pre class=\"wp-block-code\" aria-describedby=\"shcb-language-1\" data-shcb-language-name=\"HTML, XML\" data-shcb-language-slug=\"xml\"><span><code class=\"hljs language-xml\">document.head.insertAdjacentHTML(\"beforeend\", `<span class=\"hljs-tag\">&lt;<span class=\"hljs-name\">style<\/span>&gt;<\/span><span class=\"css\"><span class=\"hljs-selector-tag\">html<\/span><span class=\"hljs-selector-pseudo\">:not(<\/span><span class=\"hljs-selector-attr\">&#91;lang]<\/span>),\n<span class=\"hljs-selector-tag\">html<\/span><span class=\"hljs-selector-attr\">&#91;lang=<span class=\"hljs-string\">\"\"<\/span>]<\/span> {\n  <span class=\"hljs-attribute\">border<\/span>: <span class=\"hljs-number\">2px<\/span> dotted red <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/*  highlight images missing alt text *\/<\/span>\n<span class=\"hljs-selector-tag\">img<\/span><span class=\"hljs-selector-pseudo\">:not(<\/span><span class=\"hljs-selector-attr\">&#91;alt]<\/span>) {\n  <span class=\"hljs-attribute\">filter<\/span>: <span class=\"hljs-built_in\">blur<\/span>(<span class=\"hljs-number\">5px<\/span>) <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/* highlight on all elements that are inside of lists but not a list item &lt;li&gt; and displays them with a red outline.*\/<\/span>\n<span class=\"hljs-selector-pseudo\">:is(ul<\/span>, <span class=\"hljs-selector-tag\">ol<\/span>) &gt; *<span class=\"hljs-selector-pseudo\">:not(li)<\/span> {\n  <span class=\"hljs-attribute\">outline<\/span>: <span class=\"hljs-number\">2px<\/span> dotted red <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/* highlight on links without valid href attribute *\/<\/span>\n<span class=\"hljs-selector-tag\">a<\/span><span class=\"hljs-selector-pseudo\">:not(<\/span><span class=\"hljs-selector-attr\">&#91;href]<\/span>),\n<span class=\"hljs-selector-tag\">a<\/span><span class=\"hljs-selector-attr\">&#91;href=<span class=\"hljs-string\">\"#\"<\/span>]<\/span>,\n<span class=\"hljs-selector-tag\">a<\/span><span class=\"hljs-selector-attr\">&#91;href=<span class=\"hljs-string\">\"\"<\/span>]<\/span>,\n<span class=\"hljs-selector-tag\">a<\/span><span class=\"hljs-selector-attr\">&#91;href*=<span class=\"hljs-string\">\"javascript:void(0)\"<\/span>]<\/span> {\n  <span class=\"hljs-attribute\">outline<\/span>: <span class=\"hljs-number\">2px<\/span> dotted red <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/* highlights label with invalid for attribute *\/<\/span>\n<span class=\"hljs-selector-tag\">label<\/span><span class=\"hljs-selector-pseudo\">:not(<\/span><span class=\"hljs-selector-attr\">&#91;for]<\/span>),\n<span class=\"hljs-selector-tag\">label<\/span><span class=\"hljs-selector-attr\">&#91;for=<span class=\"hljs-string\">\"#\"<\/span>]<\/span>,\n<span class=\"hljs-selector-tag\">label<\/span><span class=\"hljs-selector-attr\">&#91;for=<span class=\"hljs-string\">\"\"<\/span>]<\/span> {\n  <span class=\"hljs-attribute\">border<\/span>: <span class=\"hljs-number\">2px<\/span> dotted red <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/* Avoids div buttons from hell. More details in https:\/\/www.htmhell.dev\/2-div-with-button-role\/ *\/<\/span>\n<span class=\"hljs-selector-tag\">div<\/span><span class=\"hljs-selector-attr\">&#91;role=<span class=\"hljs-string\">\"button\"<\/span>]<\/span> {\n  <span class=\"hljs-attribute\">color<\/span>: red;\n  <span class=\"hljs-attribute\">text-decoration<\/span>: blink <span class=\"hljs-meta\">!important<\/span>;\n}\n\n<span class=\"hljs-comment\">\/* highlight on empty anchors\/buttons *\/<\/span>\n<span class=\"hljs-selector-tag\">button<\/span><span class=\"hljs-selector-pseudo\">:empty<\/span>,\n<span class=\"hljs-selector-tag\">a<\/span><span class=\"hljs-selector-pseudo\">:empty<\/span> {\n  <span class=\"hljs-attribute\">border<\/span>: <span class=\"hljs-number\">2px<\/span> dotted red <span class=\"hljs-meta\">!important<\/span>;\n}<\/span><span class=\"hljs-tag\">&lt;\/<span class=\"hljs-name\">style<\/span>&gt;<\/span>`);<\/code><\/span><small class=\"shcb-language\" id=\"shcb-language-1\"><span class=\"shcb-language__label\">Code language:<\/span> <span class=\"shcb-language__name\">HTML, XML<\/span> <span class=\"shcb-language__paren\">(<\/span><span class=\"shcb-language__slug\">xml<\/span><span class=\"shcb-language__paren\">)<\/span><\/small><\/pre>\n\n\n<p><\/p>\n<\/details>\n\n\n\n<p>Not that you should be pasting code that strangers give you into the console. But ya know, we&#8217;re cool. <\/p>\n","protected":false},"excerpt":{"rendered":"<p>Will Mendes has a bit of CSS to highlight accessibility issues on HTML elements. Things like missing alt text and labels that aren&#8217;t linked properly to inputs. If you want to try it out quick on a website, I wrapped it in a little injection JavaScript so you could paste it in the console wherever. [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":7421,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"sig_custom_text":"","sig_image_type":"featured-image","sig_custom_image":0,"sig_is_disabled":false,"inline_featured_image":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[29],"tags":[49,7,3],"class_list":["post-7418","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-the-beat","tag-accessibility","tag-css","tag-javascript"],"acf":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/frontendmasters.com\/blog\/wp-content\/uploads\/2025\/10\/czNmcy1wcml2YXRlL3Jhd3BpeGVsX2ltYWdlcy93ZWJzaXRlX2NvbnRlbnQvbHIvcHg2NjgwNjMtaW1hZ2Uta3d2eGxmYXEuanBn.webp?fit=1024%2C683&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/posts\/7418","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/comments?post=7418"}],"version-history":[{"count":2,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/posts\/7418\/revisions"}],"predecessor-version":[{"id":7420,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/posts\/7418\/revisions\/7420"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/media\/7421"}],"wp:attachment":[{"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/media?parent=7418"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/categories?post=7418"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/frontendmasters.com\/blog\/wp-json\/wp\/v2\/tags?post=7418"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}