Well, my app was working locally but after I deployed it to Heroku and try to run it I got folowing error:
GET https://thawing-ravine-65106.herokuapp.com/assets/js/burger.js net::ERR_ABORTED 404 (Not Found) thawing-ravine-65106.herokuapp.com/:1 Refused to apply style from 'https://thawing-ravine-65106.herokuapp.com/assets/css/burger_style.css' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.
It is dissapointing! It was very chalenging homework and I was happy when I got it working locally. Now I have to work on debuging it.