How to mark up this simple construction according to BEM?

Question

HTML

I'm trying to understand BEM, I'm not sure that I understand the concept correctly.
If you are familiar with BEM, could you mark up this simple construction as an example?
https://codepen.io/anon/pen/ReOqgM

Answer 1

div__title for title
div__button (if needed) btn double class for button (I don't know why p inside button)
div__text for paragraphs