title: How to anchor the viewport to the bottom of the div that slides up?
body: <p>Simplifying the issue...</p>
  <p>I've got a div right above the footer.
  After 2 secs I want the div to reveal its content.
  Div contains some dinamically loaded things that most likely would make it over 100vh in height.
  I want the viewport to stay at the bottom of the page (follow the footer) but it goes up following the div.</p>
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-css lang-css prettyprint-override"><code>.irrelevant-top-of-the-page{
  height: 50vh;
  width: 100%;
  background: yellow;
  }
  
  .the-div{
  max-height: 0;
  width: 100%;
  background: blue;
  overflow: hidden;
  animation: slideIt 2s 2s forwards;
  }
  
  @keyframes slideIt {
  100% {
    max-height:150vh;
  }
  
  }
  
  .footer{
  height: 20vh;
  width: 100%;
  background: black;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div class="page"&gt;
    &lt;div class="irrelevant-top-of-the-page"&gt;&lt;/div&gt;
    &lt;div class="the-div"&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;p&gt;Content&lt;/p&gt;
    &lt;/div&gt;
    &lt;div class="footer"&gt;&lt;/div&gt;
  &lt;/div&gt;</code></pre>
  </div>
  </div>
  </p>