I made a responsive off-canvas navigation that’s easy to implement and doesn’t require much in the way of additional markup. The bulk of the display styles are separated in the SCSS, so you don’t have to worry about stripping out a bunch of display styles that you almost certainly don’t want.
One of these days I might get around to making some fancier options for it, but this gets the job done for now.
You can fork it on GitHub or see it in action on CodePen. Enjoy!