Support mobile devices on public forms

I finally got my hands on one of those mobile devices, which I noticed people were using when they go outside, or sit on their couch, or when they don't have access to a personal computer, such as those found at the library or in science labs.

When I tried to use a donation form, the default CiviCRM form looked like this:

This seems rather difficult to read.

I know real hackers can write CSS, but maybe we can fix this in the default CiviCRM installation?