Give a fragment link an up-transition attribute to animate between
the old and new fragment.
<div class="story">
<h1>The first story</h1>
<a href="story2.html" up-transition="move-left" up-target=".story">
Show next story
</a>
</div>
<div class="story">
<h1>The second story</h1>
<a href="story1.html" up-transition="move-right" up-target=".story">
Show previous story
</a>
</div>