process.env.NODE_ENV variables into scss via rollup - sass

Question

Is there a way to reference a process.env.NODE_ENV in a scss file by passing it to the sass-loader in postcss for rollup. If so anyone know how to go about this?
UPDATE1
Ok, so this is my rollup.config.js. I'm getting a weird issue where sometimes the $env is undefined and sometimes it is set to the right process.env.NODE_ENV
import serve from "rollup-plugin-serve";
import livereload from "rollup-plugin-livereload";
import babel from '#rollup/plugin-babel';
import { nodeResolve } from '#rollup/plugin-node-resolve';
import commonjs from '#rollup/plugin-commonjs';
import replace from '#rollup/plugin-replace';
import postcss from 'rollup-plugin-postcss';
import { uglify } from 'rollup-plugin-uglify';
const build = process.env.BUILD ? process.env.BUILD : 'development';
export default {
input: "src/index.js",
output: {
file: "dist/bundle.js",
sourcemap: true,
compact: true
},
plugins: [
postcss({
use: {
sass: {
data: "$env: " + process.env.NODE_ENV + ";"
}
},
}),
nodeResolve({
extensions: [".js"],
}),
replace({
'process.env.NODE_ENV': JSON.stringify(build)
}),
babel({
presets: ["#babel/preset-react"],
}),
commonjs(),
build === 'production' && uglify(),
serve({
verbose: true,
contentBase: ["", "public"],
host: "localhost",
port: 3000,
}),
build === 'development' &&
livereload({ watch: "dist" }),
]
};