Here are screen grabs of, first, part of the text on the web page, in a handsome serif font
second, screen grab of the same text in DTPro, converted into an unattractive sans and very large. So is there some standard sans serif font at the heart of most web pages, and our browser transforms it into a different font depending on what a particular computer has in its font library?
This is a relatively new event, maybe starting six months ago, and I end up reducing font size and changing the font on everything, one at a time.