Fix for #356 and some other changes

594141f Usernames are truncated if longer than max-width.
56f1c1e &  a39c7ee Using vw instead of em for caption sizes because they change the font-size based on the size of the window/viewport.
54699c1 Changed height property to min-height so that when the width of the windows becomes too small, the height increases.

Tested in: Firefox 31.0, IE 11.0.9, Chrome 36.0.1985 & Maxthon 4.4.1