Center Notifications On Screen?

Can someone tell me how to center notifications on screen? I use version 4.3.7

Play with top and right below and add them to the .css editor in themes,

the below settings would get you roughly centre

.notification-container {
    position: fixed;
    top: 300px;
    right: 350px;
    z-index: 1022;
    min-width: 300px;
    width: 40%;

Does this work on all resolutions?