docs: clean up env vars

Author: balazsorban44

docs/pages/getting-started/deployment.mdx

@@ -11,18 +11,12 @@ import { Accordion, Accordions } from "@/components/Accordion"
   distinguished from other environment variables more easily.
 </Callout>
 
-Auth.js libraries require you to set an `AUTH_SECRET` environment variable. This is used to encrypt cookies and tokens. It should be a random string of at least 32 characters. On UNIX based systems you can use this command:
+Auth.js libraries require you to set an `AUTH_SECRET` environment variable. This is used to encrypt cookies and tokens. It should be a cryptographically secure random string of at least 32 characters:
 
 ```bash npm2yarn
 npm exec auth secret
 ```
 
-Alternatively, you can use the following `openssl` command, which should be available on all Linux / Mac OS X systems.
-
-```bash
-openssl rand -base64 33
-```
-
 If you are using an [OAuth Provider](/concepts/oauth), your provider will provide you with a **Client ID** and **Client Secret** that you will need to set as environment variables as well (in the case of an OIDC provider, like Auth0, a third `issuer` value might be also required, refer to the provider's specific documentation).
 
 <Callout type="info">

docs/pages/guides/environment-variables.mdx

@@ -36,18 +36,12 @@ AUTH_SECRET="This is an example"
 </Code.Express>
 </Code>
 
-`AUTH_SECRET` is a random token used by the library to encrypt tokens and email verification hashes, and it's mandatory to keep things secure (See [Deployment](/getting-started/deployment) to learn more). You can use the CLI to generate an auth secret.
+`AUTH_SECRET` is a random token used by the library to encrypt tokens and email verification hashes, and it's mandatory to keep things secure (See [Deployment](/getting-started/deployment) to learn more). You can use the CLI to generate an auth secret:
 
 ```bash npm2yarn
 npm exec auth secret
 ```
 
-Alternatively, on Linux and Mac OS X based systems you can use the `openssl` CLI.
-
-```bash
-openssl rand -base64 33
-```
-
 ## Environment Variable Inference
 
 Auth.js is automatically configured to pick the right environment variables for `clientId` and `clientSecret` when using an [official OAuth provider](/getting-started/authentication/oauth).