.admin__menu #menu-magento-backend-mbmenu > a::before {
    content: '' !important;
    background: url(../images/module-icon2.png) no-repeat 0px 0px;
    margin: 0 auto .3rem;
    width: 28px;
    height: 25px;
    background-size: 26px auto;
}
#menu-magento-backend-mbmenu > a:hover::before, 
#menu-magento-backend-mbmenu._show > a::before ,
.admin__menu #menu-magento-backend-mbmenu > a:hover:before {
    background: url(../images/module-icon1.png) no-repeat 0px 0px !important;
    background-size: 26px auto !important;
}
.admin__menu [data-ui-id^="menu-mavenbird-"] .submenu-group-title span:before {
    background: url(../images/module-icon2.png) no-repeat;
    width: 24px;
    height: 20px;
    content: '';
    display: inline-block;
    margin-right: 8px;
    vertical-align: top;
    background-size: 100% auto; 
}
.admin__menu #menu-magento-backend-mbmenu .submenu-group-title span:before { display: none;}
.config-nav .tab-mavenbird-extensions .admin__page-nav-title strong { display: flex; align-items: center; } 
.config-nav .tab-mavenbird-extensions .admin__page-nav-title strong:before { 
    background: url(../images/module-icon.png) 0 0 no-repeat;
    width: 26px;
    height: 24px;
    content: '';
    display: inline-block;
    margin-right: 8px;
    vertical-align: top;
    background-size: 100% auto; 
}