If you got a transparent header, it does not play well with the cart icon. The cart icon should adapt the colors & transparency of the header.
See the following, wrong example:
https://drive.mandelkind.cloud/index.php/s/N19Eav0hm2yxj8P
Till this is integrated into the official Enfold release, you may use the following CSS snippet as a temporary workaround:
@media all and (min-device-width: 768px){
#top .av_header_transparency ul.cart_dropdown{
border:0;
}
#top .av_header_transparency a.cart_dropdown_link{
background-color:inherit;
color:inherit;
}
}