.slds-welcome-mat__info.welcome-image {
    background-image : url('PC_Framework_WelcomeMat_BackgroundImage');
}

@media (min-width: 1025px) {
    .slds-welcome-mat__info.tbid-welcome-image {
	    background-image : url('PC_Framework_TBID_Desktop_WelcomeMat_BackgroundImage');
	}
}

@media (max-width: 480px) {
    .slds-welcome-mat__info.tbid-welcome-image {
        background-image: url('PC_Framework_TBID_Mobile_WelcomeMat_BackgroundImage');
    }
}