Scroll To CK does not work when Using another link

Hello, I try to use Scroll To CK with a link that I've put into custom module like it is indicated in your How to use with Using another link.

Here is my link : <p><a href="#container-header-booking-form" class="scrollTo">Click me to scroll</a></p>

This link gives only simple link without scroll button appearance. 

I don't understand how to point the scroll button to the target link.

Best regards.