Hi Shivkumar,
Thanks for contacting syncfusion forums.
We suggest you to use CustomCSS or set AutoFormat property and remove the “-moz-border-radius” style for displaying the Accordion without rounded corners. Here we have attached a sample with custom css for achieving your requirement and the sample can be downloaded from the following link,
Accordion_CustomCSS-1202740245.zipYou can alter the attached css file based on your needs. You may also refer the following documentation link to know more details on setting the appearance of the Accordion control,
http://help.syncfusion.com/ug_93/User%20Interface/ASP.NET%20MVC/Tools/Documents/syncfusionthemes.htmKindly refer the attached sample and let us know if it helps.
Regards,
Varalakshmi R.S