When I browse (in IE 11) to a page with Localhost in URL (e.g. http://localhost:8070/MyApp/Login.aspx) everything works. The page is responsive and Bootstrap 3 classes work.
When I browse to the same page, in the same browser, using the server name (e.g. http://ServerName:8070/MyApp/Login.aspx) the Bootstrap classes are not used.
In Developer Tools, Network, I verified that in both cases, all scripts and stylesheets are loaded.
I traced this issue to the following difference in the Developer Tools DOM Explorer. The Style pane in the case of running the page with Localhost has "@media all and (min-width:768px)" in many places. But the Style pane, when executing the page with the ServerName has not references to "@media.."
This is the only difference. Why? and what am I missing?