I want to be able to display dynamic syntax trees on a webpage, possibly with a jQuery component. To show you what I mean, this

is a syntax tree, and this is the general way I want it to be displayed.
How do I build something like this with HTML and CSS?
edit: Solution
Just in case somebody who finds this question later is trying the same, here's what I did:
I ended up drawing the tree with Graphviz as an SVG, and then, moving the svg tree inside the DOM using some magic. That way I could still interact with the elements, e.g. drag&drop or hover/click events.
The result can be seen here.