Baseline Styleguide
A styleguide with no style of its own, but nevertheless providing the basic requirements any look-and-feel guidelines must conform to.
See also
For writing (rather than presentation), see Agaric’s Content Style Guide.
Links
Links should look different than regular text, strong text, or emphasized text. They should have a hover state that communicates they are interactive, and should have a distinct active and visited state. When setting the hover state of links, be sure to include focus state as well, to help readers using assistive technologies and touch devices.