Just Finished Portfolio Project, question about nav menu

Just finished my portfolio project, any and all feedback would be helpful!!
Id really like to know why my header menu wont open from collapsed

It is looking good but the navigation on mobile is not working.

I cant seem to figure out why, everything looks fine to me.

In codepen, go to Settings > then javascript and add two scripts there. First jquery and second bootstrap 3. It will fix the issue. Basically that toggle button needs JavaScript to work as required.