How to handle css urls when paths.base is set

[raythurnvoid]

I've a custom paths.base value in my svelte.config.js:

{
	kit: {
		...
		paths: {
			base: '/custom'
		},
		...
	}
};

and I load an image from the static folder in style tag:

<style>
	.body {
		background: url(/bg.jpg);
	}
</style>

I expect the URL to be transformed in /custom/bg.jpg.

I know in the script tag I have access to import { base } from '$app/paths'; but how do you handle it in the style tags ?