To do this for Chrome, all you need is the popular Stylus extension [1] and OP can upload it to userstyles.org [2] for even more convenience (don't need to download a CSS file). Also to be even more Windows 95-ey I recommend making the top links (new, past, etc.) look like a tab bar! (I really like the way the footer links look like a status bar.) [1] https://chrome.google.com/webstore/detail/stylus/clngdbkpkpe... [2…
As an alternative you can post (or link) your style at https://greasyfork.org/ which newly supports Stylus user.css style format or even self-host the file somewhere (github perhaps). Seems PR is opened already: https://github.com/chowderman/Hacker95/issues/2)