diff --git a/core/core.libraries.yml b/core/core.libraries.yml
index fb13d9c..e735efa 100644
--- a/core/core.libraries.yml
+++ b/core/core.libraries.yml
@@ -612,6 +612,9 @@ jquery.ui.spinner:
   version: *jquery_ui
   js:
     assets/vendor/jquery.ui/ui/jquery.ui.spinner.js: {}
+  css:
+    component:
+      assets/vendor/jquery.ui/themes/base/jquery.ui.spinner.css: {}
   dependencies:
     - core/jquery.ui
     - core/jquery.ui.widget