diff --git a/web/modules/custom/figli_compta_ledger/css/home.css b/web/modules/custom/figli_compta_ledger/css/home.css
index fa9c73c..5de3b30 100644
--- a/web/modules/custom/figli_compta_ledger/css/home.css
+++ b/web/modules/custom/figli_compta_ledger/css/home.css
@@ -132,6 +132,10 @@ html.gin--dark-mode #figli-home-app {
 #figli-home-app tfoot {
   position: sticky;
   bottom: 0;
+  /* Higher than thead (2) and the sticky group-row headers (1) -- without
+     this, tfoot had no explicit z-index (auto), so a group-row header
+     scrolling underneath it painted on top instead of behind. */
+  z-index: 3;
 }
 
 #figli-home-app tr.figli-totals-row td {