While I'm suggesting changes, you should probably make it clear that you have to link in bootstrap and font-awesome explicitly in your template to make all the styling work. I initially assumed that it was somehow included in tetra and it took me a second to work out why all the styling was missing.
Yea, I got that. But if someone is just following along the demo in the docs they won't get the results they'll be expecting unless they add bootstrap and font-awesome. It's probably worth mentioning that they should add the relevant imports to the template index.html for the demo.