Responsive Styles Not Applying at Any Breakpoint

Hello,

I'm having an issue with my responsive styles not displaying at any break point. If I open the page in the upfront editor, I can see my responsive styles, but when I open the page in the browser or on my phone, I do not see the responsive styles.

For instance
In Browser (Notice the navigation styles) https://www.dropbox.com/s/40acr6ces8eo0hg/Screenshot%202016-08-23%2009.37.30.png?dl=0

In Upfront https://www.dropbox.com/s/igxp2j51btpumfh/Screenshot%202016-08-23%2009.40.52.png?dl=0

How might I fix this display issue? Thanks.