User blog comment:Ducksoup/The Future of Infoboxes on Wikia/@comment-848088-20150825223207/@comment-388207-20150826011845

You would use  ... And then on your css file you would set something like this .pi-theme-Air { background:#DFF; border:solid 3px #ADD8E6; }  .pi-theme-Dark { background:#ebebef; border:solid 3px #191970; }  .pi-theme-Earth { background:#FEC; border:solid 3px #960; }  .portable-infobox { background:#B0E0E6; border:solid 3px #1390FF; } Its probably not perfect, but hopefully should kickstart your migration.

I noticed that your inforbox use tabber, which I am not sure if it is supported yet other than with a few hacks.