Alternatives to Word/LaTeX

I wrote my undergrad thesis using Word. Overall I managed to get the job done, but as with all WYSIWYG editors, by the end I feel like I had created a bit of a mess. It didn't show, but I know it's there. Soon I'm going to start writing my postgrad thesis, and I'd like to use a tool that gives me more control over the single elements. The obvious choice seems to be LaTeX, but as I'm going to be writing a thesis about humanistic matters, I wouldn't be using all its advanced features. Also, it's something I don't know, and it would take me a while to learn how to use it properly.

But here's what I was thinking. I know HTML. I know CSS. (I used to be a web developer, as a matter of fact.) Is there any tool that relies on these instruments? Of course I could just do it normally and write a HTML file and be done with it, but I don't know if there are tools that help with bibliography, summaries, menu levels etc.

It seems to me that with HTML5 and all the technological advancements, this might be the way to go. I'd like to hear your opinions about this, and also if there are any other tools I'm not aware of, thanks.