.toolbar-icon-admin-toolbar-tools-help {
    text-indent: -9999px;

}

.toolbar-icon-admin-toolbar-tools-help:before {
    background-image: url(../misc/icons/ffffff/d8-item.svg);
    padding-bottom: 0;
    padding-left: 4px;
    padding-right: 8px;
    padding-top: 2px;
}
.toolbar-icon-admin-toolbar-tools-help:active:before,
.toolbar-icon-admin-toolbar-tools-help.active:before {
    background-image: url(../misc/icons/ffffff/d8-item.svg);
}