wix.com but got frustrated when he wasn't able to customize the interaction the way he wanted to.
For simple stuff like this, it's generally easier to build up from scratch than to hack a generated page's complex HTML. It was an interesting challenge to make a system that would be easy for my cousin to customize without mucking with code; I use "data-" tags so that the "table of content" type links know what section to open, and it should be pretty easy work to show him the structures to use.
I didn't have a lot of placeholder content to work with, and I was having trouble getting traction without it, so I generated a bunch of images and thumbnails. I parsed out some colors from w3schools' html color page and http://listofrandomwords.com/ for words (got my editor macro mojo working to push it into code) I then made a image generator in processing for the squares, fullsize and thumbnail.
I took a snapshot of its current state and put it in my devblog archive. But one cool thing is we were able to grab the domain WDJ3.com (his initials) -- always fun to find a relevant 4-letter .com domain!