Add sign up and create application flow to Next.js Quickstart (#1499)

docs/quickstarts/nextjs.mdx

@@ -48,18 +48,24 @@ description: Add authentication and user management to your Next.js app with Cle
 
   ### Set your environment variables
 
-  <SignedIn>
-    Add the following keys to your `.env.local` file. These keys can always be retrieved from the [API Keys](https://dashboard.clerk.com/last-active?path=api-keys) page of your Clerk Dashboard.
-  </SignedIn>
-
-  <SignedOut>
-    1. Navigate to the [Clerk Dashboard](https://dashboard.clerk.com/last-active?path=api-keys){{ track: 'exp_create_account_nextjs_quickstart' }}.
-    1. In the top navigation, select **Configure**. Then in the sidebar, select **API Keys**.
-    1. In the **Quick Copy** section, copy your Clerk publishable and secret key.
-    1. Paste your keys into your `.env.local` file.
-
-    The final result should resemble the following:
-  </SignedOut>
+  <If condition={experiment.enabled}>
+    <ExperimentCreateAccountFromDocsQuickstart params={experiment} />
+  </If>
+
+  <If condition={!experiment.enabled}>
+    <SignedIn>
+      Add the following keys to your `.env.local` file. These keys can always be retrieved from the [API Keys](https://dashboard.clerk.com/last-active?path=api-keys) page of your Clerk Dashboard.
+    </SignedIn>
+
+    <SignedOut>
+      1. Navigate to the [Clerk Dashboard](https://dashboard.clerk.com/last-active?path=api-keys){{ track: 'exp_create_account_nextjs_quickstart' }}.
+      1. In the top navigation, select **Configure**. Then in the sidebar, select **API Keys**.
+      1. In the **Quick Copy** section, copy your Clerk publishable and secret key.
+      1. Paste your keys into your `.env.local` file.
+
+      The final result should resemble the following:
+    </SignedOut>
+  </If>
 
   ```env {{ filename: '.env.local' }}
   NEXT_PUBLIC_CLERK_PUBLISHABLE_KEY={{pub_key}}