diff --git a/packages/theme/base/vite.config.js b/packages/theme/base/vite.config.js
index 5e8379be8e..650ea69426 100644
--- a/packages/theme/base/vite.config.js
+++ b/packages/theme/base/vite.config.js
@@ -22,6 +22,11 @@ export default defineConfig({
       name: 'theme-base',
       fileName: () => 'index.js',
       formats: ['es']
+    },
+    rollupOptions: {
+      output: {
+        banner: 'import "./style.css"'
+      }
     }
   }
 })