Further CSS tuneups

This keeps both page title and tank title left, but one above
the other. This means that it will work better on narrow screens.

Also changed all black to #222222 and all white to #efefef. These
were already the colors of choice, but I hadn't been applying them
properly.

Got rid of bold in the header.

Adjusted footer to be smaller and for peermore icon to blend.

Fixed a problem with header margin-bottom being inconsistent.

At some point will probably want to move all the css into one file
and rationalize it. I can scss or similar calling.