diff --git a/src/Gateway.php b/src/Gateway.php
index 34662f4..42b7136 100644
--- a/src/Gateway.php
+++ b/src/Gateway.php
@@ -71,7 +71,7 @@ public function __construct( Config $config ) {
 
 		$ideal_issuer_field->set_options(
 			new CachedCallbackOptions(
-				function() {
+				function () {
 					return $this->get_ideal_issuers();
 				},
 				'pronamic_pay_ideal_issuers_' . \md5( \wp_json_encode( $config ) )
@@ -89,7 +89,7 @@ function() {
 
 		$credit_card_issuer_field->set_options(
 			new CachedCallbackOptions(
-				function() {
+				function () {
 					return $this->get_credit_card_issuers();
 				},
 				'pronamic_pay_credit_card_issuers_' . \md5( \wp_json_encode( $config ) )
@@ -124,7 +124,7 @@ private function get_ideal_issuers() {
 
 		$ideal_methods = array_filter(
 			$methods,
-			function( $method ) {
+			function ( $method ) {
 				return is_array( $method ) && isset( $method['PaymentMethodCode'] ) && 'IDEAL' === $method['PaymentMethodCode'];
 			}
 		);