Grey border around every widget

Hi guys,
I tried twice to get help in the other forum on your homepage, but I haven’t got an answer (I know you are busy!)… so I try again here.

Any widget I use is surrounded by a grey thick frame that does not go away. I have tried several different codes to customise it, but nothing has worked so far! I do not want to get rid of the frames completely, but I want to customise them whenever needed.

Hope I can get some help! One example is here: http://friends-4-friends.org/engagement/ (around the images and the title). It is especially not nice around the button-widget.

Thanks in advance,

Barbara

https://ww.wp.xz.cn/plugins/siteorigin-panels/