diff --git a/packages/uebertool-companion/modules/uebertool_twig/src/Twig/Extension/TwigExtrasExtension.php b/packages/uebertool-companion/modules/uebertool_twig/src/Twig/Extension/TwigExtrasExtension.php
index 856c1d1..e312f74 100644
--- a/packages/uebertool-companion/modules/uebertool_twig/src/Twig/Extension/TwigExtrasExtension.php
+++ b/packages/uebertool-companion/modules/uebertool_twig/src/Twig/Extension/TwigExtrasExtension.php
@@ -399,10 +399,10 @@ public function HTML($html) {
   /**
    * Shortcut for create_attribute().addClass().
    *
-   * @param array $classes
+   * @param string|array $classes
    * @return string
    */
-  public function classList(array $classes) {
+  public function classList(string|array $classes) {
     $attribute = new Attribute();
     $attribute->addClass($classes);
     return $attribute;