[Hỏi đáp] How to make my forum header fixed ( no page load)

I want to make my forum header fixed(no page load). Other contents will load, but the header+navlinks+fm toolbar should be fixed.
As example you can see facebook or http://www.computerhope.com/

My forum: http://www.bdtipsntricks.com/
Version: PunBB

Answer: https://devs.forumvi.com/t462-hoi-dap-how-to-make-my-forum-header-fixed-no-page-load?showpost=p2867

Temp: Move #pun-intro and #pun-head out of .pun
CSS: Apply position:fixed and width:100% for those two