The 108 bytes in question:

    @charset "UTF-8";
    img,canvas,iframe,video,svg{max-width:100%}
    .overflow-container{overflow-y:scroll;
    -webkit-overflow-scrolling:touch}

Analysis (EDIT):

I'm not sure why the CSS needs to be declared as containing UTF-8 since all the characters of the file are part of the US-ASCII range.

Use the .overflow-container on tables and pre/code blocks. "-webkit-overflow-scrolling" seems to be useful to allow horizontal scrolling on overflow elements on iOS [1].

* [1]: http://stackoverflow.com/questions/15605085/webkit-overflow-...