Default twenty eleven search box formatting

The best way I can describe my issue is by:

1. going to this blog link

2. maximize browser(watch search box in the header)

3. resize browser manually drag(watch search box at about 50% of max browser size)

problem: the search box loses its position and pops up and over the main title.

Anyone know how I can fix this and just keep it inline as the first 50% of the browser resize? Maybe somewhere or fix it to where it will not move?

thank you!

Alex