/* Keeps iframe canvases transparent in dark mode. NOT a bwin theme — bwin now ships its own dark theme, applied via the theme="dark" attribute on bw-window (see react-bwin's react-bwin.css / the CDN bwin.css). All that remains here is the color-scheme concern below. Used in two contexts: - The docs site: linked from src/app/layout.js. - The standalone iframe examples (public/*.html): linked there directly. Scope note: loaded by BOTH the docs site and the iframes, so it must only set color-scheme on :root. Do NOT add a `body` rule here — the iframe canvas is transparent (see below) so it already shows the parent's dark background, and a `body` rule would leak into the docs site and override globals.css's themed body. */ :root[data-theme='dark'] { /* Keeps the iframe canvas transparent so the parent docs page's dark background shows through (the iframe sets no background of its own). A browser only renders an iframe's canvas transparent when its used color-scheme MATCHES the embedder's; mismatched schemes force an opaque canvas of the iframe's own default — i.e. WHITE here, the bug you see if this line is removed. Setting `dark` matches the dark parent, restoring transparency. (Opened standalone with no parent, this instead yields the UA's own dark canvas — also correct.) */ color-scheme: dark; }