Yes;
https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=2964653957

The bright white overlay that shows up when your like, editing the transport lines. Can that be changed to a darker grey?

Now allows changing of the accent colour.
More mods are supported.
Still haven't found what controls the tooltip colour.

@Elje0ett, this mod makes the game world darker AND it has a morning (low-sun) setting: https://www.transportfever.net/filebase/index.php?entry/5942-natural-environment-professional-2

Thanks to Yoshi. DarkUI no longer replaces vanilla files, meaning it wont break as soon as UG updates.

Looks I included an edited cockpit view file without realising.
It's removed now.

you lose some read out in first person, bottom centre screen, and bottom left.

To be honest this mod is not so helpful because the game world is very lit so the dark UI won't help if you don't want to blow out your eyeballs but I still like the mod very much and the idea :)

damn, nice long monitor