diff --git a/c3l_membership/static/style.css b/c3l_membership/static/style.css
--- a/c3l_membership/static/style.css
+++ b/c3l_membership/static/style.css
@@ -19,3 +19,18 @@ p {
   text-align: right;
   padding-bottom: 1rem;
 }
+
+.form-error {
+  background: #f98691;
+  border: 1px solid #dc3545;
+  border-radius: 4px;
+  padding: 0.5em 0.6em;
+  font-weight: 550;
+  color: #3d0309;
+}
+
+.field-error {
+  background: #f98691;
+  border: 1px solid #dc3545;
+  color: #3d0309;
+}