asset/css-in-script
A Script imports a stylesheet. yuanme bundles the stylesheets that Pages link with <link rel="stylesheet">, not those a Script imports, so the CSS would never reach a Page. This includes a package whose own JS imports CSS, which can’t be used yet.
Example
import "./photo.css";
Fix
Delete the import, and import the stylesheet from one that a Page links instead, as the help shows: @import "/scripts/photo.css";, or for a package, its CSS file, such as @import "nprogress/nprogress.css";. The suggested edit deletes the import.