Add some instructions

hbbs/static/css/styles.css

@@ -112,3 +112,7 @@ ul {
 #programmes-explanation {
   margin-bottom: 20px !important;
 }
+
+#participate-text p:nth-child(n + 2) {
+  margin-top: 20px !important;
+}

hbbs/templates/participate.html

@@ -1,9 +1,25 @@
 {% extends "layout.html" %}
 
 {% block content %}
+  <div id="participate-text">
   <p>
     We're exploring peer-to-peer technologies for file sharing through our own
     networks. Due to the copyright regime, we're still in friend-to-friend
     networking mode. We're lurking in <a href="https://cell.hbbs.decentral1.se">cell.hbbs.decentral1.se</a>.
   </p>
+  <p>
+    Practically speaking, we're using the latest version of the <a
+    href="https://github.com/datproject/dat/releases/tag/v14.0.2">Dat
+    command-line interface</a> for sharing. In order to join in, you'll need
+    to download the Dat client for your operating system
+    (<a href="https://github.com/datproject/dat/releases/download/v14.0.2/dat-14.0.2-linux-x64.zip">Linux</a>,
+    <a href="https://github.com/datproject/dat/releases/download/v14.0.2/dat-14.0.2-macos-x64.zip">MacOS</a>,
+    <a href="https://github.com/datproject/dat/releases/download/v14.0.2/dat-14.0.2-win-x64.zip">Windows</a>)
+    unzip it and test that it works (on GNU/Linux that is usually tested with the
+    following commands: sudo apt install -y unzip; unzip
+    dat-14.0.2-linux-x64.zip; cd dat-14.0.2-linux-x64; ./dat --version) and
+    then speak further with others on our
+    <a href="https://cell.hbbs.decentral1.se/brewers/channels/file-sharing">file sharing</a> channel.
+  </p>
+  </div>
 {% endblock %}