Make layout responsive

[cornelius]

The layout assumes a certain width right now. It should still render nicely without horizontal scrolling for smaller widths, e.g. on a tablet or on a phone.

[nanduni-nin]

In order to make responsive layouts, I have several suggestions.
- Use frameworks like W3.CSS which is free to use and no license necessary.
- Set a meta view port tag, create a flexible layout / fluid grid, use media queries in CSS file
Do you have any better suggestion on this?

[cornelius]

The site is simple enough, so I would prefer to avoid pulling in a framework. By eliminating assumptions about the screen size and possibly introducing media queries it should be possible to make the site responsive.

[cornelius]

Done, released, and published now.