Why is responsive navigation not working?

Question

css

The adaptive menu does not work, the code is here , although the code is written one to one as in the video tutorial.

Answer 1

Your option:

<button type="button" class="navbar-toggle" data toggle="collapse" data target="#responsive-menu">

Correct option:

<button type="button" class="navbar-toggle" data-toggle="collapse" data-target="#responsive-menu">

Dash missed in data-toggleanddata-target

Answer 2

and it does not work either locally or on codepen