Configure postcss-import to allow "@import" anywhere on a file?

Question

While using the latest version of postcss-import, I've noticed that it only allows @import statements at the top of the files similar to this:

@import "button.css;

.some-class {
  color: red;
}

My question here is, is there some way to configure postcss-import to allow @import statements anywhere in the file? Similar to this:

.some-class {
  color: red;
}

@import "button.css;

I'm aware this goes against the upcoming CSS standard. However, I believe I've seen this live in a project and I'm curious how to configure this. This is my postcss.config.js file:

module.exports = {
  plugins: [
    require('postcss-import'),
  ]
}

Thanks