MediaWiki:Common.css

Note: After publishing, you may have to bypass your browser's cache to see the changes.

Firefox / Safari: Hold Shift while clicking Reload, or press either Ctrl-F5 or Ctrl-R (⌘-R on a Mac)
Google Chrome: Press Ctrl-Shift-R (⌘-Shift-R on a Mac)
Edge: Hold Ctrl while clicking Refresh, or press Ctrl-F5.

/* Center the logo vertically in Vector skins */
.vector-header-logo, .mw-logo-icon {
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    height: 100px !important;     
    width: 100px !important;     
    background-size: contain !important;
    background-repeat: no-repeat !important;
    background-position: center center !important;
    padding: 0 !important;
    margin: 0 !important;
    box-sizing: border-box !important;
}