I generally keep a few things like this on hand as starting points, and then build my own additional CSS rules, and maybe a few purely presentational classes on top in an additional stylesheet. The "Cascading" part of Cascading Style Sheets is a beautiful thing. ;)

@sdan: Thanks much for those links, BTW. Super-helpful stuff right there. https://newcss.net/ is my current favorite, but it's nice to have so many options now to play with. :)