Bootstrap navbar not working

#1

Hi,
the bootsrap nav is not showing in large window. It is showing as a “-”.

below is my codepen link.

Can anyone see what is the fault.

#2

yes, Codepen uses version 4 of bootstrap. Go to css setting and replace the link to bootstrap 4 with this: https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css it is version three

#3

Thanks for your help

#4