feat: Add a landing page for NGINX Gateway Fabric (#911)

This commit adds a landing page for NGINX Gateway Fabric. Custom
landing pages allow us to draw a reader's attention towards the
documentation they would find most useful as both a prospective
or returning user, such as evergreen reference material.

Author: ADubhlaoich

content/ngf/_index.md

@@ -1,11 +1,79 @@
 ---
+# The title is the product name
 title: NGINX Gateway Fabric
+# The URL is the base of the deployed path, becoming "docs.nginx.com/<url>/<other-pages>"
 url: /nginx-gateway-fabric/
-cascade:
+# The cascade directive applies its nested parameters down the page tree until overwritten
+cascade: 
+  # The logo file is resolved from the theme, in the folder /static/images/icons/
   logo: NGINX-Gateway-Fabric-product-icon.png
   nd-banner:
     enabled: true
     type: deprecation
     start-date: 2025-05-30
     md: /_banners/ngf-2.0-release.md
----
+# The subtitle displays directly underneath the heading of a given page
+nd-subtitle: Implement the Gateway API across hybrid and multi-cloud Kubernetes environments with a secure, fast, and reliable NGINX data plane.
+# Indicates that this is a custom landing page
+nd-landing-page: true
+# Types have a 1:1 relationship with Hugo archetypes, so you shouldn't need to change this
+nd-content-type: landing-page
+# Intended for internal catalogue and search, case sensitive:
+# Agent, N4Azure, NIC, NIM, NGF, NAP-DOS, NAP-WAF, NGINX One, NGINX+, Solutions, Unit
+nd-product: NGF
+---
+
+## About
+
+NGINX Gateway Fabric provides an implementation of the [Gateway API](https://gateway-api.sigs.k8s.io/) using [NGINX](https://nginx.org/) as the data plane. The goal of the project is to implement the core Gateway APIs needed to configure an HTTP or TCP/UDP load balancer, reverse proxy, or API gateway for Kubernetes applications.
+
+For a list of supported Gateway API resources and features, see the [Gateway API Compatibility]({{< ref "/ngf/overview/gateway-api-compatibility.md" >}}) documentation.
+
+## Featured content
+
+{{<card-layout>}}
+  {{<card-section showAsCards="true" isFeaturedSection="true">}}
+    {{<card title="Get started" titleUrl="/nginx-gateway-fabric/get-started">}}
+      Use kind to quickly deploy and test a NGINX Gateway Fabric cluster.
+    {{</card>}}
+    {{<card title="Deploy NGINX Gateway Fabric" titleUrl="/nginx-gateway-fabric/install">}}
+      Choose how to deploy NGINX Gateway Fabric in production.
+    {{</card>}}
+    {{<card title="Changelog" titleUrl="/nginx-gateway-fabric/changelog">}}
+      Review the changes from the latest releases.
+    {{</card>}}
+  {{</card-section>}}
+{{</card-layout>}}
+
+## Design
+
+NGINX Gateway Fabric separates the control plane and data plane into distinct deployments. The control plane interacts with the Kubernetes API, watching for Gateway API resources. 
+
+When a new Gateway resource is provisioned, it dynamically creates and manages a corresponding NGINX data plane Deployment and Service.
+
+Each NGINX data plane pod consists of an NGINX container integrated with [NGINX Agent](https://github.com/nginx/agent). The control plane translates Gateway API resources into NGINX configurations and sends these configurations to the agent to ensure consistent traffic management.
+
+This design enables centralized management of multiple Gateways while ensuring that each NGINX instance stays aligned with the cluster’s current configuration.
+
+For more information, see the [Gateway architecture]({{< ref "/ngf/overview/gateway-architecture.md" >}}) topic.
+
+## More information
+
+{{<card-layout>}}
+
+{{<card-section showAsCards="true">}}
+    {{<card title="Gateway API compatibility" titleUrl="/nginx-gateway-fabric/overview/gateway-api-compatibility/">}}
+      View how much of the Gateway API NGINX Gateway Fabric supports.
+    {{</card>}}
+    {{<card title="Technical specifications" titleUrl="/nginx-gateway-fabric/reference/technical-specifications/">}}
+      Check which versions of NGINX Gateway Fabric match the API.
+    {{</card>}}
+    {{<card title="Routing traffic to applications" titleUrl="/nginx-gateway-fabric/traffic-management/basic-routing/">}}
+      Create simple rules for directing network traffic with HTTPRoute resources.
+    {{</card>}}
+    {{<card title="Secure traffic using Let's Encrypt and cert-manager" titleUrl="/nginx-gateway-fabric/traffic-security/integrate-cert-manager/">}}
+      Implement HTTPS with Let's Encrypt to secure client-server communication.
+    {{</card>}}
+{{</card-section>}}
+
+{{</card-layout>}}