This is exactly what is working for MY layout
.sf-icon-cont:hover, .sf-hover .sf-icon-cont, .sf-icon-box[class*="icon-box-boxed-"] .sf-icon-cont, .sf-hover {
background-color: #ffffff;
}
.sf-icon-cont.cont-small .sf-icon {
color: #888888;
}
.sf-icon-cont.sf-icon-icon-four:hover, .sf-hover .sf-icon-cont.sf-icon-icon-four, .sf-icon-box[class*="icon-box-boxed-"] .sf-icon-cont.sf-icon-icon-four, .sf-hover .sf-icon-box-hr.sf-icon-icon-four {
background-color: #ffffff;
}
.ss-icon, .ss-icon.ss-gizmo, [class^="ss-"]:before, [class*=" ss-"]:before, .ss-gizmo[class^="ss-"]:before, .ss-gizmo[class*=" ss-"]:before, .right[class^="ss-"]:after, .right[class*=" ss-"]:after, .ss-gizmo.right[class^="ss-"]:after, .ss-gizmo.right[class*=" ss-"]:after {
color: #888888;
}
.sf-icon-cont.sf-icon-icon-four:hover .sf-icon, .sf-hover .sf-icon-cont.sf-icon-icon-four .sf-icon, .sf-icon-box.sf-icon-box-boxed-one.sf-icon-icon-four .sf-icon, .sf-icon-box.sf-icon-box-boxed-three.sf-icon-icon-four .sf-icon {
color: #888888;
}
But, I repeat, I’m not so happy for this solution.