On my phone, in the Opera browser there is a feature called night mode. This turns white pages dark to reduce eye strain. Usually this works really well. For example on Wikipedia.
However on Mediawiki with Timeless it doesn't work properly. Most icons (edit and history, etc) goes black against dark background. I don't know why. It could be a problem in the browser too. However since the other mobile themes seem to work, I'll start by reporting here.
Interesting is that two icons at the top work right.