Creating mobile theme

Just a quick question to see if people can help me out on a header design question I have.

I have just got a logo designed, which I amwanting to intergrate into my blog, but I want to make it look good on mobile browsers as well as desktop browsers. The best website I have seen that accomplishes this is the Yoast website.

How does the Yoast website accomplish the 3 different states. I have looked at the site on my desktop web browser and resized the browser and it goes from the normal state, to the normal state without the Yoast logo, then it finally goes to the full blown mobile web view (small nav bar at the top).

How can this be achieved, or are there any plugins?

I could integrate the logo into my design as it is, but this would look terrible on mobile browsers (as I currently don’t have a logo, so it’s just text that is scaled).

Thanks for any advice on mobile theme options.