diff --git a/agaric/css/agaric.css b/agaric/css/agaric.css
index 480454e..5287ed8 100644
--- a/agaric/css/agaric.css
+++ b/agaric/css/agaric.css
@@ -10483,6 +10483,15 @@ a.navbar-link:hover,
 .titlebar + .byline {
   margin-top: 1.5rem; }
 
+.header-search .form-submit.button {
+  font-size: 1.25rem; }
+
+.header-search .form-text.input {
+  font-size: 1.25rem; }
+  @media screen and (min-width: 769px), print {
+    .header-search .form-text.input {
+      width: 20em; } }
+
 .hero.is-dark .tabs a,
 .is-dark .tabs a {
   color: #3276CF; }