Break point for Hamburger menu

[BaguetteAgile]

Hello everyone, I'm using the navbar in Silex V3 and I wanted to know what the break point values are for the hamburger menu.
I've made a site, but live on a smartphone the hamburger menu doesn't appear.

Here's the link:

http://d777153fa9b44c3695dc74f460529794.testurl.ws/

Thanks a lot.

[BaguetteAgile]

The breakpoints are too small, is it possible to change them?

Thank you.