So, if you still want to work on xymon’s pages themes, it’s not that difficult. I mean, it is design-wise, but technically it’s not.
There are different kinds of pages (status, log, info, history, …) but they all have a common menu and each page consists of a header, a footer, the common menu and a generated body with the status, data, report, history, etc..
I first started adding the bootstrap 4, jquery and a few other javascript files in the footer, an extra css file and a few modifications on the colors to make it a more flat look ‘n’ feel.
Some things are hardcoded, but this is open source, so you can change the body generation too, if you want.
more on that later …