When vite bundles css, image url() paths, they are relative to the dist directory in the theme.
However, when the css is loaded on the page by drupal, the path is relative to the web root.
The base can be set to the theme directory, but this breaks dev mode.
The workaround is to define images in css as relative to the web root. Vite build will throw an error, but it will work when loaded on the page.
This may be fixable with environment variables, a dynamic base path, or a postcss plugin.
Active
2.0
Configuration
This plugin may be helpful: https://www.npmjs.com/package/postcss-url/v/7.3.2
Some experimental config:
https://git.drupalcode.org/project/unocss_starter/-/blob/0.2.x/demo/unoc...