Hi, just wondering if some others ran into this. I just started the book and cdnjs.cloudflare provided Bootstrap 4, instead of 3. I understand that it is under beta, but I went ahead with using it. My output displayed in the browser didn’t quite match. It looks as if the class (.panel and .panel-body) was removed and is replaced by (.card and card-block).
It will look similar to the book using the new classes.