Lead Developer
I just updated the code to be more current: https://gist.github.com/generatepress/c23aef2d05807c39bb32
It should display the mobile search icon in the navigation now 🙂
Documentation: http://docs.generatepress.com/
Adding CSS: http://docs.generatepress.com/article/adding-css/
Ongoing Development: https://generatepress.com/ongoing-development