Update environment-variables.md

docs/docs/environment-variables.md

@@ -6,7 +6,11 @@ You can easily provide environment variables to your site.
 
 For JavaScript loaded into the browser, just add a `.env.development` and/or `.env.production` file in your root folder for development or production builds respectively. The environment variables are embedded during build time using Webpack's [DefinePlugin](https://webpack.js.org/plugins/define-plugin/). Because these variables are provided at build time, you will need restart your dev server or rebuild your site after changing them.
 
-To add environment variables for the JavaScript run in node.js, e.g. in `gatsby-config.js` or `gatsby-node.js`, you can use the NPM package [dotenv](https://www.npmjs.com/package/dotenv). Once you've installed dotenv and followed their setup instructions, you can use your environment variables in the same way as shown in the example below.
+In addition to `.env.*` files, any variable in the environment prefixed with `GATSBY_` will be made available in browser JavaScript.
+
+To add environment variables for the JavaScript run in node.js, e.g. in `gatsby-config.js` or `gatsby-node.js`, you can add environment variables the normal ways e.g. when calling gatsby on the command line or by adding environment variables through your hosting/build tool.
+
+If you want to access variables in `.env.*` files in your node.js code, use the NPM package [dotenv](https://www.npmjs.com/package/dotenv). Once you've installed dotenv and followed their setup instructions, you can use your environment variables in the same way as shown in the example below.
 
 ## Example
 
@@ -25,8 +29,6 @@ API_URL=https://example.com/api
 
 These variables will be available to your site as `process.env.API_URL`.
 
-In addition any variable in the environment prefixed with `GATSBY_` will be available.
-
 ## Example
 
 ```