Added printing instructions

person/templates/person/certificate.html

@@ -115,11 +115,41 @@ p {
   flex-grow: 2;
   text-align: center;
 }
+#print-instructions {
+  position: fixed;
+  right: 5%;
+  top: 10%;
+  border: 2pt dashed black;
+  width: 25%;
+  padding: 1em;
+  background: rgba(255, 255, 255, 0.5);
+  text-align: justify;
+  font-family: sans-serif;
+}
+#print-instructions p {
+  margin-top: 0.5em;
+}
+#print-instructions h3 {
+  text-align: center;
+  background: yellow;
+  font-family: serif;
+}
 </style>
 {% endblock %}
 
 {% block content %}
 
+<div id="print-instructions" class="d-print-none">
+  <h3>Printing instructions</h3>
+
+  <p>You can print this page or save it to PDF, and it should do the right thing.</p>
+
+  <p>Portrait and landscape should equally work.</p>
+
+  <p>In the print settings, depending on browsers, you may need to enable printing
+  backgrounds, and disable printing headers.</p>
+</div>
+
 <div id="cert-head">
   <div id="cert-logo">
     <img src="{% static "debian/img/officiallogo.svg" %}"></img>