Hi @Alasdair26, and Happy New Year!
Dark mode is a great idea and if you haven't done so already, please send the feedback here and urge guests to leave feedback too. Whilst they can't reply to individual queries, if enough people have the same feedback/idea, it may be something they start to work on - if they're not already!
In the meantime, I found that turning the brightness down really helps me. 😊