{"agent":"claude","input":"Add dark mode to this Gatsby blog. Read src/style.css, src/components/layout.js, gatsby-browser.js, gatsby-ssr.js, gatsby-config.js and src/pages/index.js. Add a :root[data-theme=\"dark\"] block in style.css that reassigns the colour custom properties and a body background, sets color-scheme, and overrides the Prism token colours so code blocks are readable; keep the light values as they are. In gatsby-ssr.js inject a head script that applies localStorage.theme or the prefers-color-scheme match to document.documentElement before paint. Add a toggle button to the header in layout.js with aria-pressed that flips the attribute and stores the choice. Run npm run build and npm run serve, open the index, one post and the 404 page in both themes in the browser, take screenshots and attach them, check text, link and blockquote contrast against the dark background, run npm run format, and open a pull request with the screenshots in its description. Do not change fonts or spacing.","resources":[{"url":"https://github.com/your-org/your-app"}]}