Hello, Minimal,
The border was added using custom CSS code for that particular demo. To remove it, please go to Theme Options > Theme Custom CSS > Global > find and delete the code of border – https://prnt.sc/UgAtEF5nzl6r
If you have any additional questions or concerns, please do not hesitate to reach out to us. Our support team is always available to assist you.
Kind Regards,
8theme team