Use custom Environment Variables F7

Hi! I am new with F7 and I decided to use the CLI to generate a framework7 React app. I succeed setting up the a minimal firabase config but now I want to save the API key and that sensitive stuff in environment variables for a future production model. I have attempted with webpack DefinePlugin, defining the variables with Cross-Env, writing them in a .env file and nothing works for me. I assume that the project is not the guilty since the project is just right from scratch and node base code is changed yet. Moreover, I haven’t find anyone who has used environment variables either in Vue.js F7 app what is starting to worry me. Any help is welcome, thanks!!