Hi Keir,
We are really sorry but we are unable to view your screenshots, so please check once.
And regarding the media boxes which is kept in the demo is in different styles, so if you go to the theme package you can find the html snippets folder where you can get the code of media boxes in different or you can check it in the tutorial.
“User agent stylesheet” is from the browser itself, if you want to overwrite these stylesheet then you need to take a proper css selector and write the custom css accordingly. For Reference:- http://www.w3schools.com/cssref/css_selectors.asp
Please let us know if we are understanding you fully or if perhaps this is not what you meant.
We look forward to your response
Thanks
