Add online services URL

config.php.example

@@ -2,3 +2,5 @@
 
 $contact_name = "Example Contact";
 $contact_link = "https://example.com";
+
+$online_services_source_url = "https://example.com";

index.php

@@ -64,7 +64,11 @@
       <?php endif; ?>
     </main>
     <footer>
-      <p>In case of any questions, message <a href="<?= $contact_link ?>"><?= $contact_name ?></a>.</p>
+      <p>
+        Online services are <a class="blend" href="<?= $online_services_source_url ?>">open source</a>.
+        <br>
+        In case of any questions, message <a href="<?= $contact_link ?>"><?= $contact_name ?></a>.
+      </p>
 
       <?php if (!empty($version)): ?>
       <p>

styles.css

@@ -221,3 +221,7 @@ footer {
   background-position: center;
   background-size: contain;
 }
+
+.blend {
+  color: inherit !important;
+}