The slide show is a great set of standards and guidelines to follow. I use them all the time, looking for patterns and repetition in my designs, then factoring those out to components.
Navigation, Panel, Grid, Repeater, Card, etc. These are all common components I design for each site.
I also have separate CSS files for Utilities, Page and Content. Utilities stores things like my clearfix or margin normalizer, Page stores overall site layout (header, footer, main), and Content is a universal set of rules for headings, paragraphs, links, lists, etc. site-wide.
