Added <a>, <em> to preview.html paragraph
Added open & close iconfont Fallback backgrounds

Research shows that 370Million Devices do not support @font-face as of
2013. so I added fallback backgrounds for the Mobile nav buttons.
src:
https://docs.google.com/presentation/d/1n4NyG4uPRjAA8zn_pSQ_Ket0RhcWC6Ql
Z6LMjKeECo0/edit?pli=1#slide=id.p