Click anywhere on the screen or press any key to toggle the
<div> between hidden and showing.
<div> element that transitions between
display: none; opacity: 0 and
display: block; opacity: 1. Neat, huh?
This is another paragraph to show that display: none; is being
applied and removed on the above <div> . If only its
opacity was being changed, it would always take up the space in
the DOM.