sorry but i was looking at the source of a couple different 90s websites that existed in the pre-CSS era and honestly it's so simple. they display perfectly on mobile devices and desktop screens. and they all use the <center> tag to centre content on the screen and it's just so much more elegant than all the modern CSS equivalents sorry.
seriously. go look at some 90s-era sites right now. go to the old Space Jam site or the Heaven's Gate site. go to CNN'S OJ Trial page. pull them up on your phone. they work. they look good. they're easy to navigate. they're simple under the hood. maybe we shouldn't be so quick to abandon and deprecate simple things that work well?