Repository: create-react-app
Issue: postcss-modules-values variables isn't working in a non-module css/scss files
Labels: issue: bug

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### Desribe the bug

postcss-modules-values variables aren't working on non-module CSS/SCSS files

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Yes, I already tried using css/scss files to know which one works but no luck, variables isn't working on non-module css/scss files


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Can't find any solutions, "postcss-modules-values variables isn't working on non-module/ regular css/scss files"


### Environment

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  System:
    OS: Windows 10
    CPU: (6) x64 Intel(R) Core(TM) i5-8600K CPU @ 3.60GHz
  Binaries:
    Node: 10.16.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.15.2 - C:\Program Files (x86)\Yarn\bin\yarn.CMD
    npm: 6.9.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: 44.17763.1.0
    Internet Explorer: 11.0.17763.1
  npmPackages:
    react: ^16.8.6 => 16.8.6
    react-dom: ^16.8.6 => 16.8.6
    react-scripts: 3.0.1 => 3.0.1
  npmGlobalPackages:
    create-react-app: Not Found

### Steps to reproduce

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1. I'm using postcss-modules-values library for creating variables for my css-modules
2. variables isn't working on a regular / non-modules css/scss files, I could use css variables but I don't want to refactor my codes because I'm already using postcss-modules-values, in my previous project i'm using gatsby and it works fine even with non-module css/scss files
3. it works without an error but the variable values aren't there, 
4. as much as possible I don't like to eject my project, It'll be my last resort if ever.


### Expected behavior

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I expect that the variables created from postcss-modules-values are available with module and non-module css/scss files. Because it behave exactly like this in my gatsby-project.


### Actual behavior

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Nothing went wrong it works without an error, but If I import my variables to a non-module css/scss files the variable value isn't read or simply the variables isn't working.

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the bug is understandable even without a bug demo, maybe it's a web pack config issue, I just want you to know that it behaves differently in create-react-app. it works perfectly in other setups like gatsby.


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