Midnight Lizard will help you to customise an appearance of the entire internet in order to make it easier to use.
You can set up different color schemes for each favorite website and one default theme for all other sites.
Choose from the predefined schemes or create your own. Number of user color schemes is unlimited.
Why not just "Midnight" instead of "Midnight Lizard"?
Really injoyed it the past few days, hope to see it coming on FF soon :)