{#- The one theme line the server cannot render: resolving `auto`. Every other theme is written onto server-side (ADR-0029), but `auto` means *what the OS is asking for*, and only the browser knows that. The stylesheet follows it through a prefers-color-scheme query; Bootstrap's own chrome needs a concrete `data-bs-theme`, so these three lines set it. Two properties are load-bearing, and both are why this is inline rather than a file under static/: * **First thing inside .** It has to land before anything paints, or a page flashes light chrome on a dark canvas. A `defer`red external script runs after the document is parsed — far too late — and a blocking `