The jumbotron is a Bootstrap component highlighting the key message of your website. More information about the jumbotron and its HTML markup can be found at the following URL: http://v4-alpha.getbootstrap.com/components/jumbotron/.
In this section, we'll customize the jumbotron to display our client's big welcome message with stylistic touches in line with her mockup. This will include adding a large background image, enlarging the welcome message text, and then adjusting its presentation for multiple viewports.
index.html, find the following markup:
<!-- INTRO SECTION --> <section class="jumbotron" id="welcome"> <div class="container"> <h1 class="display-3"><strong>Big</strong> Welcome Message</h1> <p class="lead"> ...