This isn't much of a how to as it is a tip.
After logging onto tryhackme for some learning I was blinding with the white and figured there had to be an easier way to view this site.
They don't have a dark mode, so with a little google searching I found an extension called Dark Reader. Add this to your browser and you'll have dark mode pretty much everywhere. You should be able to find it here: dark reader extension
Seems to have a few nice features as well: