docs: new intro page

backend/docs/pages/intro/intro.md

@@ -0,0 +1,113 @@
+<!---
+  Copyright 2026 SECO Mind Srl
+
+  SPDX-License-Identifier: Apache-2.0
+-->
+
+# Edgehog
+
+![Backend CI](https://github.com/edgehog-device-manager/edgehog/actions/workflows/backend-ci.yaml/badge.svg)
+![Frontend CI](https://github.com/edgehog-device-manager/edgehog/actions/workflows/frontend-ci.yaml/badge.svg)
+![Coverage](https://img.shields.io/coverallsCoverage/github/edgehog-device-manager/edgehog)
+
+**License:** Apache 2.0 — [apache.org/licenses/LICENSE-2.0](http://www.apache.org/licenses/LICENSE-2.0.html)
+
+An open-source IoT device fleet management platform built on [Astarte](https://github.com/astarte-platform/astarte). Manage hardware, push firmware updates, track device health, and automate deployments — all through a single GraphQL API.
+
+## What Edgehog does
+
+<div class="feature-cards">
+<div class="feature-card">
+<div class="card-icon" style="background: #e0f5f0;">📡</div>
+<h3>Device management</h3>
+<p>Register and monitor your entire device fleet. Query real-time status: online/offline state, last-seen IP, cellular connectivity, battery, OS info, and hardware details.</p>
+</div>
+
+<div class="feature-card">
+<div class="card-icon" style="background: #fff4e0;">🔄</div>
+<h3>OTA update campaigns</h3>
+<p>Create base image collections and roll out firmware upgrades across device groups using campaigns.</p>
+</div>
+
+<div class="feature-card">
+<div class="card-icon" style="background: #e8f0ff;">📦</div>
+<h3>Container deployments</h3>
+<p>Define applications as versioned releases of containers. Deploy, upgrade, start, stop, and delete containerized workloads via deployment campaigns.</p>
+</div>
+
+<div class="feature-card">
+<div class="card-icon" style="background: #fce8f0;">📊</div>
+<h3>Fleet grouping</h3>
+<p>Tag devices freely and write selector expressions to form dynamic groups that update automatically.</p>
+</div>
+
+<div class="feature-card">
+<div class="card-icon" style="background: #eaf3de;">📍</div>
+<h3>Geolocation</h3>
+<p>Track device position and location data reported from the field. Query per-device position and last-seen coordinates through the API.</p>
+</div>
+
+<div class="feature-card">
+<div class="card-icon" style="background: #eeedfe;">🔗</div>
+<h3>Remote Forwarding</h3>
+<p>Request and manage forwarder sessions to tunnel traffic to specific devices for diagnostics and remote access — configurable per tenant.</p>
+</div>
+</div>
+
+## API reference
+
+### Admin REST APIs
+
+Edgehog admin tasks (i.e., managing tenants) are available through a REST API. It supports creating, updating and deleting tenants
+
+**Endpoint**
+
+```
+http://<your-host>/admin-api/v1/
+```
+
+Replace `<your-host>` with your Edgehog instance hostname.
+
+**Full API docs** available here: [admin-rest-api](admin-rest-api/)
+
+### Tenant GraphQL APIs
+
+All Edgehog operations are exposed through a **GraphQL API**. It supports queries, mutations, and real-time subscriptions.
+
+**Endpoint**
+
+```
+http://<your-host>/tenants/<your-tenant>/api
+```
+
+Replace `<your-host>` with your Edgehog instance hostname and `<your-tenant>` with the slug of your tenant.
+
+**Full API docs** available here: [tenant-graphql-api](tenant-graphql-api/)
+
+#### Key resources
+
+| [**Queries**](https://docs.edgehog.io/0.12/tenant-graphql-api/#group-Operations-Queries) | Query your device data. |
+| [**Mutations**](https://docs.edgehog.io/0.12/tenant-graphql-api/#group-Operations-Mutations) | Make changes and interact with Edgehog. |
+| [**Subscriptions**](https://docs.edgehog.io/0.12/tenant-graphql-api/#group-Operations-Subscriptions) | Subscribe to events as they happen. |
+
+## How to read this documentation
+
+**1. Core concepts**
+
+Before exploring features or the API, read the [Core concepts](core_concepts-1.html) page. It defines the building blocks (**Hardware Types**, **Devices**, **System Models**, **Groups**, and **Selectors**) that all other sections depend on.
+
+**2. Follow the feature guides**
+
+The sidebar organizes topics from setup (hardware types, system models) to operations (OTA updates, campaigns, container deployments). Work through them sequentially: each guide builds on the vocabulary established by the previous one.
+
+**3. Use the API reference for integration work**
+
+The [GraphQL API reference](https://docs.edgehog.io/0.12/tenant-graphql-api/) lists every query, mutation, and subscription with argument types and example payloads. Use it alongside the feature guides when building integrations or automating fleet operations.
+
+**4. Note features marked as planned**
+
+Sections marked with an asterisk (\*) (such as Attributes and Attribute filters) describe functionality planned for a future release. The selector syntax for attributes is already in place, but attribute population is not yet active. Treat these sections as forward reference only.
+
+**5. Download or explore offline**
+
+An ePub version of the full documentation is available at the bottom of any page. A [llms.txt](llms.txt) is also provided for machine-readable consumption.

backend/docs/style/cards.css

@@ -0,0 +1,59 @@
+/*
+ * This file is part of Edgehog.
+ *
+ * Copyright 2026 SECO Mind Srl
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+.feature-cards {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
+    gap: 1.25rem;
+    margin: 2rem 0;
+}
+
+.feature-card {
+    background: #ffffff;
+    border: 1px solid #e8e8e8;
+    border-radius: 12px;
+    padding: 1.5rem;
+    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
+}
+
+.feature-card .card-icon {
+    width: 48px;
+    height: 48px;
+    border-radius: 10px;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    font-size: 1.5rem;
+    margin-bottom: 1rem;
+}
+
+.feature-card h3 {
+    font-size: 1rem;
+    font-weight: 700;
+    margin: 0 0 0.5rem 0;
+    color: #1a1a1a;
+}
+
+.feature-card p {
+    font-size: 0.9rem;
+    color: #555;
+    line-height: 1.6;
+    margin: 0;
+}

backend/mix.exs

@@ -142,14 +142,19 @@ defmodule Edgehog.MixProject do
   # Add here additional documentation files
   defp docs do
     [
-      main: "intro_user",
+      main: "intro",
       logo: "docs/images/logo-favicon.png",
       javascript_config_path: "../versions.js",
       extras: Path.wildcard("docs/pages/*/*.md"),
       filter_modules: ~r/Edgehog/,
-      assets: %{"docs/images/" => "assets"},
+      assets: %{"docs/images/" => "assets", "docs/style/" => "style"},
+      before_closing_head_tag: fn
+        :html -> ~s(<link rel="stylesheet" href="style/cards.css">)
+        _ -> ""
+      end,
       api_reference: false,
       groups_for_extras: [
+        Introduction: ~r/intro/,
         "User Guide": ~r"/user/",
         "OTA Updates": ~r"/ota_updates/",
         "Containers management": ~r"/containers/",