List Nextcloud's enterprise offering and the NC app "Roundcube Mail"

This adds three new boxes to the 'About' and 'Download' pages in the known layout and style.

Author: pabzm

about/index.html

@@ -119,7 +119,7 @@ <h2 id="license">License <a class="anchor" href="#license" aria-label="Link to t
 
 <div class="row">
     <div class="col">
-        <h2 id="services">Services Using and Supporting Roundcube <a class="anchor" href="#services" aria-label="Link to this section: Services Using and Supporting Roundcube"></a></h2>
+        <h2 id="services">Services using and supporting Roundcube <a class="anchor" href="#services" aria-label="Link to this section: Services Using and Supporting Roundcube"></a></h2>
         <p>
             There are thousands of services that make use of Roundcube to provide
             webmail to millions of users. We love to see our application in so many hands
@@ -137,6 +137,23 @@ <h2 id="services">Services Using and Supporting Roundcube <a class="anchor" href
 </div>
 
 <div class="row row-cols-1 row-cols-md-2 row-cols-lg-3">
+    <div class="col my-3">
+        <div class="card h-100">
+            <div class="card-header bg-header">
+                <a href="https://nextcloud.com" class="text-white" target="_blank">Nextcloud</a>
+            </div>
+            <div class="card-body">
+                <p>
+                    <a href="https://nextcloud.com" class="rc-icon external-link" target="_blank">Nextcloud</a>
+                    develops software for decentralized and federated clouds as alternative to centralized cloud services.
+                </p>
+                <p>
+                    Since 2023 it is the new home of Roundcube and fosters the growth and improvement of the project.
+                </p>
+            </div>
+        </div>
+    </div>
+
     <div class="col my-3">
         <div class="card h-100">
             <div class="card-header bg-header">

download/index.html

@@ -134,9 +134,41 @@ <h2 id="plugins">Plugins and skins <a class="anchor" href="#plugins" aria-label=
 <p>Roundcube uses <a href="https://getcomposer.org" class="rc-icon external-link" target="_blank">Composer</a> to manage add-ons and dependencies. Our <a href="https://plugins.roundcube.net/" class="rc-icon external-link" target="_blank">Plugins Repository</a>
     contains a list of plugins and instructions on how to install them and keep them up-to-date. As well as plugins you'll also find <a href="https://packagist.org/?type=roundcube-skin" class="rc-icon external-link" target="_blank">additional skins</a> available on Packagist.</p>
 
+<h2 id="integrations">Integrations <a class="anchor" href="#integrations" aria-label="Link to this section: Integrations"></a></h2>
+
+<div class="row row-cols-1 row-cols-md-2 row-cols-lg-3">
+    <div class="col my-3">
+        <div class="card h-100">
+            <div class="card-header bg-header">
+                <span class="text-white">Nextcloud integration: Roundcube Mail</span>
+            </div>
+            <div class="card-body">
+                <p>
+                    <a href="https://apps.nextcloud.com/apps/mail_roundcube" target="_blank"><img src="/images/nextcloud-roundcube-main-window.png" style="max-width: 100%;" /></a>
+                    The Nextcloud app <a href="https://apps.nextcloud.com/apps/mail_roundcube" target="_blank">"Roundcube Mail"</a> integrates an existing Roundcube standalone email-webapp into Nextcloud, with optional SSO.
+                </p>
+            </div>
+        </div>
+    </div>
+
+</div>
+
+
 <h2 id="packages">Complete email server packages with Roundcube <a class="anchor" href="#packages" aria-label="Link to this section: Complete email server packages with Roundcube"></a></h2>
 
 <div class="row row-cols-1 row-cols-md-2 row-cols-lg-3">
+    <div class="col my-3">
+        <div class="card h-100">
+            <div class="card-header bg-header">
+                <span class="text-white">Roundcube for Enterprises</span>
+            </div>
+            <div class="card-body">
+                <p><a href="https://nextcloud.com/roundcube/" class="fw-bold" target="_blank">Roundcube for Enterprises</a>
+                    is a stand-alone, all-in-one email solution for service providers by Nextcloud. Your customers need a reliable, dependable and performant email service. The Nextcloud Roundcube Enterprise subscription helps you deliver exactly that.
+            </div>
+        </div>
+    </div>
+
     <div class="col my-3">
         <div class="card h-100">
             <div class="card-header bg-header">