I would second Magic Banana and suggest you try emacs. Yes, screen, tmux and
byobu (which is a really front end to either screen or tmux) will achieve
what you want but emacs offers more to you as a programming environment (and
probably anything else you can think of). In particular, I've read many times
the emacs org mode is extremely useful for (literate) programming of html
particularly how it creates and manipulates tables.
A sample of what emacs can do for you ...
Working with HTML -> http://emacsrocks.com/e12.html
Multiple cursors -> http://emacsrocks.com/e13.html