I have tried these 3 CSS snippets and none have worked...
.collection-type-index #portfolio {
background-color: none, !important;
}
#collection-60285049dea9552bd2a02fd1 {
background-color: none, !important;
}
.collection-60285049dea9552bd2a02fd1 #portfolio{
background-color: none, !important;
}