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                <h1 class="border1 display-inline">We can control document flow via css display property</h1>
<h2 class="border1 display-inline">We don't have to specify default properties - since, well, they are the default!</h2>
<div class="border1 display-inline">Just another div.</div>
<span class="border2 display-block">Just another span.</span>
<span class="border2 display-block">Yet another span.</span>
<div class="border1 display-inline">Yet another div.</div>
<div class="border1 display-inline">This is a third div on this page!</div>


                .border1 { border: 5px solid gray }
.border2 { border: 5px solid tomato }
.display-block { display: block }
.display-inline { display: inline }

1. Are elements on our pages going to behave like block-level or like inline elements?
2. We have complete control over that!
3. Whatever CSS class we give our elements, that's how they'll behave!
4. Here we gave the .border2 class to our span elements so that it's obvious that they're stretching the full width of the available screen space.