Add theme info to footer

_config.yml

@@ -77,3 +77,4 @@ sphinx:
       footer_start:
         - footer-logos
         - footer-info
+        - footer-extra

_templates/footer-extra.html

@@ -0,0 +1,27 @@
+<div class="container-fluid footer-extra">
+    <div class="container">
+      <center>
+        Theme by <a href="https://projectpythia.org">Project Pythia</a>. All code
+        in Pythia Cookbooks is licensed under
+        <a href="https://opensource.org/license/apache-2-0">Apache 2.0</a>. All
+        other non-code content is licensed under
+        <a href="https://creativecommons.org/licenses/by/4.0/">
+          Creative Commons BY 4.0 (CC BY 4.0)</a
+        >.
+      </center>
+      <br /><br />
+      <div class="row">
+        <p class="m-0">
+          <img
+            src="{{ pathto('_static/footer-logo-nsf.png', 1) }}"
+            style="float: left; width: 60px; height: 60px; margin-right: 1rem"
+          />
+          This material is based upon work supported by the National Science
+          Foundation under Grant Nos. 2026863 and 2026899. Any opinions, findings,
+          and conclusions or recommendations expressed in this material are those
+          of the author(s) and do not necessarily reflect the views of the
+          National Science Foundation.
+        </p>
+      </div>
+    </div>
+  </div>