In the videogular-themes-default plugin, the videogular font is referenced by videogular.css and lives in the same directory on the server (in .woff, .svg, .eot, and .ttf formats). Different browsers produce different results rendering it. For an easy comparison, look at the "STOP" and "LOGO" buttons of Videogular's example page: http://www.videogular.com/examples/adding-your-custom-buttons/
Chrome and Firefox render it as a serif font; Safari and mobile browsers render it as a sans serif font. Which browsers are doing it correctly? What is going on?