Various visual fixes

Here are a few changes I have made, these are:

Now the intro fades out, and when that animation is finished, the what-to-build section fades in, preventing elements "jumping around" the page.

Removed the white background behind the close button, personally I think it looks better without it.

I made all buttons have consistent borders, now they all have borders on the bottom and right to give depth

Fixed the Tevko link, so it always points to http://timevko.com/

Closed a DIV tag that hadn't been closed