colorin-productions on "Mobile display shows only half the screen"

Hello,
I am using the Twenty-Twelve theme for my site, but when used on mobile phones, only half the screen is shown. I suspect it has to do with the social media icons in the header. Is there any way to fix this without having to remove them?

The site is http://quiltersdemexico.com
Here is a screenshot of how it looks on my iPhone.
I used this tutorial to add the icons.

Thanks!