xenforo how to add custom icon in widget?

.p-body-sidebar [data-widget-id="56"] .block-container { background-image:url("path_to_image"); padding-top:50px; background-size:50px 50px; background-position:center top; background-repeat:no-repeat; } OR [data-widget-key="online_now"] { .block-minorHeader:before {...