fix: add NSF footer

Signed-off-by: Henry Schreiner <henryfs@princeton.edu>

Author: henryiii

assets/css/extended/homepage.css

@@ -151,3 +151,18 @@
 .dark .project-card:hover {
   box-shadow: 0 2px 12px rgba(255, 255, 255, 0.05);
 }
+
+/* ── NSF footer ──────────────────────────────────────────────────────────── */
+.nsf-footer {
+  border-top: 1px solid var(--border);
+  padding: 1.25rem var(--gap);
+  max-width: calc(var(--main-width) + var(--gap) * 2);
+  margin: 0 auto;
+}
+
+.nsf-footer p {
+  font-size: 0.8rem;
+  color: var(--secondary);
+  line-height: 1.6;
+  margin: 0;
+}

layouts/partials/extend_footer.html

@@ -0,0 +1,5 @@
+<div class="nsf-footer">
+  <p>Support for this work was provided by NSF grant <a href="https://www.nsf.gov/awardsearch/showAward?AWD_ID=2209877&amp;HistoricalAwards=false">OAC-2209877</a>.
+  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>