Center All Header Content

Hi! This is my first time using WordPress and the Parabola theme. I have a little bit of HTML and CSS knowledge.

I’m wanting to center all the content in my header bar (excluding social links in top right). That includes the site title, tagline and navigation. You can see my site, and the header I mentioned, here – http://lorimer.id.au

I guess the easiest way to do this is with custom CSS. Can someone give me an example?