Dartik is a dark version and a sub-theme of Bartik - Drupal 7 core's default theme.
It is basically an override of all color styles from Bartik leaving all other styles untouched, to be inherited from the original theme.
The idea for a dark scheme for Bartik came up while we were thinking of improvements to the color schemes available at that time in #762468: Fix up the color schemes for Bartik but as Jen (Bartik's creator and maintainer) mention here and here - "Bartik won't work light text on dark background. Ever. Unless someone makes a contrib theme like that.... :P" - so here it is.
- Fully compatible with color module.
- Contains all RTL overrides and images needed for right-to-left sites.
- Tested as admin theme too.
Create a demo site.