Javascript help, is this even possible?

I'd like to know if you guys can help me with some javascript. I've written some code that works in replacement for the 4chan extension. It works, but i'd like to add a gap between each thread, just like the extension. Help a fellow channer out.

Pastebin with code.
http://pastebin.com/m7fac3b33

>>3
"NP complete"?
Don't get it