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


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

1. In this example all the elements are styled as block elements, even though we have two <span> elements on the page.
2. All it took was to add the property: value pair of "display: block" to our "display-block" class attribute name.