Add new Office UI Fabric Theme
It would be fantastic to have an Office UI Fabric theme to replace the SharePoint 2013 theme. This will produce a consistent experience for users in Office 365/SharePoint Online
Watch for the coming feature to add custom CSS into Style Profiles, releasing later this year for both K2 Five and K2 Cloud. You will be able to link external CSS files into your Style Profile to use in SmartForms, which should unlock this capability. Try it out when it releases and let us know your feedback. Thanks!