Skeleton

 Skeleton  is a lightweight set of CSS for making responsive sites.

Why
Skeleton can be useful if you want to add a responsive grid without using a heavy framework like Bootstrap.

Appears Abandoned
It appears that the project has been abandoned on GitHub. The last commit by the author was on 2014-12-29. As of 2016-02-19 there are 46 issues and 36 pull requests with no apparent response from the author. 

There are at least three forks of Skeleton currently:
 * https://github.com/oltmannsdaniel/skeleton-plus
 * http://legacyframework.xyz/
 * https://github.com/skeleton-framework/skeleton-framework

Issues

 * Includes utility class names prefixed with, which are parsed as microformats.

IndieWeb Examples

 * uses it on gregorlove.com since 2015-07-12.

Articles

 * To migrate to CSS Grid: