What technology stack you recommend for e-learning systems?

Hey guys,

I have a requirement which involves building something to display e-learning content.

I have read through lot of articles and i have decided to build something against using the tools available in the market. (Camptesia,Smartbuilder etc.,)

What technology stack you recommend for it?

We are planning to use a Content Management System ,a DB and some front end.

CMS - Planning to use Symfony3.
DB- PostGreS
Front End- Symfony has something to use, or else can plug through HTML5 and CSS.
Any more suggesting will be helpful , will also change the technology mentioned above as well.

The e-learning should work on laptop, desktop, mobile and also Digital Boards.