diff --git a/src/wp-admin/css/customize-controls.css b/src/wp-admin/css/customize-controls.css
index 3738f224b1..ba15d7cd56 100644
--- a/src/wp-admin/css/customize-controls.css
+++ b/src/wp-admin/css/customize-controls.css
@@ -1075,6 +1075,7 @@ p.customize-section-description {
 #available-menu-items .new-content-item .create-item-input,
 .customize-control-dropdown-pages .new-content-item .create-item-input {
 	flex-grow: 10;
+	width: 100%;
 }
 
 #available-menu-items .new-content-item .add-content,
@@ -1083,8 +1084,10 @@ p.customize-section-description {
 	flex-grow: 1;
 }
 
-.customize-control-dropdown-pages .new-content-item .create-item-input.invalid {
+.customize-control-dropdown-pages .new-content-item .create-item-input.invalid,
+.customize-control-dropdown-pages .new-content-item .create-item-input.invalid:focus {
 	border: 1px solid #dc3232;
+	box-shadow: 0 0 2px rgba(204,0,0,.8);
 }
 
 .customize-control-dropdown-pages .add-new-toggle {
diff --git a/src/wp-admin/css/customize-nav-menus.css b/src/wp-admin/css/customize-nav-menus.css
index dc4e518cad..61d8a3f33a 100644
--- a/src/wp-admin/css/customize-nav-menus.css
+++ b/src/wp-admin/css/customize-nav-menus.css
@@ -606,6 +606,7 @@
 #available-menu-items .new-content-item .create-item-input.invalid,
 #available-menu-items .new-content-item .create-item-input.invalid:focus {
 	border: 1px solid #dc3232;
+	box-shadow: 0 0 2px rgba(204,0,0,.8);
 }
 
 #available-menu-items .menu-item-handle .item-type {