svelte fails to parse valid CSS

Describe the bug svelte css parser fails to consider valid css which include backslash

Logs

from https://github.com/wighawag/a17t-svelte-test :

$ rollup -c

src/main.js → public/build/bundle.js...
[!] (plugin svelte) ParseError: RightParenthesis is expected
src\Tailwindcss.svelte
70535:     transition-delay:1000ms
70536:   }
70537: }</style>
        ^
ParseError: RightParenthesis is expected
    at error (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\utils\error.ts:25:16)
    at Parser$1.error (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\parse\index.ts:93:3)
    at Object.read_style [as read] (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\parse\read\style.ts:21:11)
    at tag (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\parse\state\tag.ts:190:27)
    at new Parser$1 (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\parse\index.ts:45:12)
    at parse (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\parse\index.ts:208:17)
    at compile (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\svelte\src\compiler\compile\index.ts:79:14)
    at C:\dev\projects\wighawag\a17t-svelte-test\node_modules\rollup-plugin-svelte\index.js:252:22
    at ModuleLoader.addModuleSource (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\rollup\dist\shared\rollup.js:17742:30)
    at ModuleLoader.fetchModule (C:\dev\projects\wighawag\a17t-svelte-test\node_modules\rollup\dist\shared\rollup.js:17796:9)

To Reproduce

git clone  https://github.com/wighawag/a17t-svelte-test
cd  a17t-svelte-test
yarn && yarn build

Expected behavior should build succesfully with css from a17t (https://github.com/milesmcc/a17t)

Stacktraces

see log above

Information about your Svelte project:

• Your operating system: Windows 10

• Svelte version : 3.23.2

• Whether your project uses Webpack or Rollup : Rollup

Severity It block me from using css library like a17t so pretty severe in my opinion

[JohnnyFun]

svelte@3.41.0 compiler gave me “RightParenthesis is expected” on this css for me just now: filter: alpha(opacity=65);.

https://svelte.dev/repl/5e7e42fe56af440f8dceaef7160f0c46?version=3.41.0

[Conduitry]

<style global> isn’t a native Svelte thing. This probably is a bug in svelte-preprocess.