Creating a Jumbotron
Many times, a designer will create a section of content that they want to call the users' attention to. This is sometimes known as a Call to Action or a Hero. Bootstrap calls this visual treatment a Jumbotron and makes up the first part of our homepage mockup that we will be creating.
In order for us to implement the Jumbotron, we need to think about how our current homepage is laid out. We have a custom block called Jumbotron placed within the Content region. This means that potentially every page will have this block. Also, every page contains a page title block as well, and based on the mockup, we don't want that to display on our homepage. So, we need to address these two tasks while modifying our page to accommodate the Jumbotron.
First, we will take advantage of Drupal's new default WYSIWYG to directly edit the source HTML. This will allow us to add HTML markup directly into our custom block without worrying about creating a Twig template for it.
Second...