add Fallback font

Author: Rokt33r

browser/styles/main/ArticleDetail.styl

@@ -143,7 +143,7 @@ infoButton()
           padding-left 20px
           text-align left
           font-size 13px
-          font-family '.HelveticaNeueDeskInterface-Regular'
+          font-family '.HelveticaNeueDeskInterface-Regular', sans-serif
           &:hover
             background-color #4297FE
             color white