#toplevel_page_wp-app-store {
    .wp-menu-image {
        background: url("../img/wpas-icon.png") no-repeat 6px -27px;
    }
    
    &.wp-menu-open, &:hover {
        .wp-menu-image {
            background-position: 6px 3px;
        }
    }
    
    img {
        display: none;
    }
}