--- title: Issue #760: Why GitHub now ships more CSS, not less —... description: A curated roundup of frontend links covering GitHub's three-year migration from CSS-in-JS (styled-components) to CSS Modules on github.com, which cut... canonical: https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Issue #760: Why GitHub now ships more CSS, not less — Frontend Focus | daily.dev og:description: A curated roundup of frontend links covering GitHub's three-year migration from CSS-in-JS (styled-components) to CSS Modules on github.com, which cut... og:url: https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye og:image: https://api.daily.dev/og/posts/Oi6kowdye.png og:image:alt: Issue #760: Why GitHub now ships more CSS, not less — Frontend Focus og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Issue #760: Why GitHub now ships more CSS, not less — Frontend Focus **[Frontend Focus](https://daily.dev/sources/ffocus)** · 3 min read · 2 upvotes · 0 comments ## Summary A curated roundup of frontend links covering GitHub's three-year migration from CSS-in-JS (styled-components) to CSS Modules on github.com, which cut server-side render time by 55% despite shipping more CSS. Also included: Anthropic's deep dive into speeding up Claude's web app (3.1s to 0.55s time-to-typeable), pure-CSS techniques for detecting element overlap and extracting grid info, an interface design cheat sheet, a Custom Attributes polyfill, a case against container-query-based fluid typography, and assorted tools including an HDR logo brightener and a glyph-mixing font tool. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why did GitHub move away from CSS-in-JS and styled-components to CSS Modules? GitHub spent three years purging styled-components and CSS-in-JS from github.com in favor of CSS Modules to improve site performance. Despite shipping more CSS overall as a result, the change cut server-side rendering time by 55%, because CSS Modules avoid the runtime cost of generating styles in JavaScript at render time. _Weighing CSS-in-JS against CSS Modules for a large codebase is easier with real migration writeups surfaced on daily.dev._ ### What is CSS Modules and how does it scope styles without a runtime cost? CSS Modules is a bundler convention, not a browser feature or web standard, where class names written in a .module.css file get rewritten to unique names at build time. This scopes styles per file automatically, avoiding class name collisions, with no JavaScript runtime overhead since the transformation happens during bundling rather than at render time. _Developers comparing styling approaches can track practical trade-offs like this on daily.dev._ ### How did Anthropic reduce the time-to-typeable for Claude's web app from 3.1s to 0.55s? Anthropic cut the 75th percentile time-to-typeable for Claude's web app from 3.1 seconds to 0.55 seconds during a focused performance sprint. Fixes included catching layout shifts too small for Cumulative Layout Shift to flag, removing a :root:has() selector that cost 24ms per DOM change, and correcting a jump caused by Chrome pre-rendering the page at the wrong height. _Engineers chasing frontend performance regressions can find similar debugging deep dives on daily.dev._ ## Similar posts on daily.dev - [Improving site performance by shipping more CSS](https://daily.dev/posts/improving-site-performance-by-shipping-more-css-gh8jxvxku) · GitHub Blog · 47 upvotes · 8 comments - [Frontend Focus Issue 738: April 22, 2026](https://daily.dev/posts/frontend-focus-issue-738-april-22-2026-cpcsl8dke) · Frontend Focus · 7 upvotes · 0 comments - [CSS-in-JS: The Great Betrayal of Frontend Sanity](https://daily.dev/posts/css-in-js-the-great-betrayal-of-frontend-sanity-yltrsmn2c) · The New Stack · 0 upvotes · 0 comments --- Tags: [#webdev](https://daily.dev/tags/webdev), [#github](https://daily.dev/tags/github), [#css](https://daily.dev/tags/css) [View this post on daily.dev](https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Issue #760: Why GitHub now ships more CSS, not less — Frontend Focus","url":"https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye"},"datePublished":"2026-09-30T15:21:17.450Z","dateModified":"2026-09-30T15:21:37.829Z","description":"A curated roundup of frontend links covering GitHub's three-year migration from CSS-in-JS (styled-components) to CSS Modules on github.com, which cut...","image":"https://media.daily.dev/image/upload/s--ZrL_HSsR--/f_auto/v1722860399/public/Placeholder%2006","thumbnailUrl":"https://media.daily.dev/image/upload/s--ZrL_HSsR--/f_auto/v1722860399/public/Placeholder%2006","isAccessibleForFree":true,"articleSection":"Frontend Focus","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Frontend Focus","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/ffocus","url":"https://daily.dev/sources/ffocus"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":2},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"webdev,github,css","timeRequired":"PT3M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Frontend Focus","item":"https://daily.dev/sources/ffocus"},{"@type":"ListItem","position":3,"name":"Issue #760: Why GitHub now ships more CSS, not less — Frontend Focus"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/issue-760-why-github-now-ships-more-css-not-less-frontend-focus-oi6kowdye#faq","mainEntity":[{"@type":"Question","name":"Why did GitHub move away from CSS-in-JS and styled-components to CSS Modules?","acceptedAnswer":{"@type":"Answer","text":"GitHub spent three years purging styled-components and CSS-in-JS from github.com in favor of CSS Modules to improve site performance. 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