:global { } don't works as expected

[Inqnuam]

Describe the bug
The entier :global {} (not :global()) is dropped.

:global() works as expected.

Logs
no log.

To Reproduce

Used config:

 sveltePreprocess({
      sourceMap: true,
 });

code:

<style>
 :global {
  .someGlobalClass {
    background-color: red;
   }
 }
</style>

Expected behavior
output something like this:

.someGlobalClass {
  background-color: red;
}

Information about your project:

• svelte-preprocess version: 6.0.3

• Whether your project uses Webpack or Rollup: none

[Conduitry]

Is your concern that the preprocessor isn't transforming that? I wouldn't expect it to. That's valid input to the compiler as of Svelte 5 - and then the compiler handles it from there.

If that's not what you're referring to, please provide a complete reproduction, not just code snippets.

[AlexRMU]

You need to turn on postcss and add the postcss-preset-env plugin.

sveltePreprocess({
  postcss: {
    plugins: [
      postcssPresetEnv(),
    ],
  },
}),