What about a dark theme from contrast mode?

Everyday I work with GitLab and I wonder, why there isn't a dark mode?

I'm fairly aware that the proposals of a full dark theme might bring developers some work, but my proposal is different.

Proposal:

Make available a "contrast mode" or something that could wipe out this much of white light everywhere.

Possible fix that could solve almost all scenarios:

html,img,svg { filter: invert(90%); }

You set this onto an white navigation bar and a solarized codebox, and you get a very beautiful full dark theme.

ps. Please note the "90%", due to the fact that a 100% would hurt our eyes just as much.

It can be a contrast checkbox, or something. Nothing fancy.. but still, a big deal.

This could really improve my nights of sleep.