I never care too much about dialogue, since most of my writing is not only non-fiction but is technical explanations. I think this talk will be helpful even if you don’t write dialogue, and will be particularly useful if you write games or UIs.
Adding background to text in D3.js is probably the hardest thing going. It has been the bane of all the graphs I have worked on lately: I know how to do it (just check the sitemap here for instance) but it’s always tricky to remember and finicky to set up and use. Always good to have a nice tutorial for it.