Custom Landing Page Issues (HTML)

Hey all,

I've been trying and trying to get a custom landing page in HTML, but I'm being faced with the error 'Html code is too long.' I have been trying to get this: http://www.blacktie.co/demo/munter/ sort of thing for a landing page.

Any ideas on how to add it or is there a way of linking HTML and CSS on different sheets?

Thanks very much in advance!