Hi @Johann_Lu ,
The styles under the edit bar are associated to cq:styleId which are stored under Template policies. You can create a custom event listener and listen to change for cq:styleId property under the content path, e.g.
/content/<pagePath>/jcr:content/root/main/responsivegrid/cards1
![anupamp17770278_0-1710413574498.png anupamp17770278_0-1710413574498.png](https://experienceleaguecommunities.adobe.com/t5/image/serverpage/image-id/71478i6E575FDB8602E6FA/image-size/medium?v=v2&px=400)