I've just released a new version of obsurvey. Now surveys embedded in blogs use precisely the same font as the blog, also the same size (example)
This eliminates the need for any kind of styling of a survey you want to embed on a blog or website. Also I've added page transitions, to make it easier to see what part of the blog has changed when you go to the next page of the survey.
Also the font size of surveys has been reduced. It was kind of big before.