title: 100vh cuts off content when window height is small
body: <p>Using 100vh for the first section so #section-1 and it's contents cover the whole viewport.</p>
  
  <p>Problem example: when the window is at 300px, upon scroll, the green background is no longer there and the content is still at the full 100vh.</p>
  
  <p>I think it might have to do with some css properties having px units or maybe it's because of the animations but I'm not sure.</p>
  
  <p>Can someone please help me figure out why?</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>#section-1 {
    background-color: #58b038;
    color: #fff;
    text-align: center;
    height: 100vh;
    margin: 0 auto;
    padding-bottom: 30px;
  }
  
  .container {
    max-width: 960px;
    margin: auto;
    padding: 30px 30px;
  }
  
  #showcase {
    height: 200px;
  }
  
  #showcase h1 {
    font-size: 50px;
    line-height: 50px;
    text-transform: uppercase;
    font-weight: bold;
    position: relative;
    animation: heading;
    animation-duration: 2s;
    animation-fill-mode: forwards;
  }
  
  @keyframes heading {
    0% {
      top: -50px
    }
    100% {
      top: 100px;
    }
  }
  
  #showcase-img {
    max-width: 300px;
    margin: 0 auto;
  }
  
  #about {
    position: relative;
    animation-name: about;
    animation-duration: 2s;
    animation-fill-mode: forwards;
  }
  
  @keyframes about {
    0% {
      left: -1000px
    }
    100% {
      left: 0px;
    }
  }
  
  #about a {
    text-decoration: none;
    color: #fff;
    font-size: 40px;
    margin: 0 10px;
  }
  
  #about p {
    line-height: 30px;
    font-size: 20px;
  }
  
  .button {
    display: inline-block;
    color: #fff;
    text-decoration: none;
    padding: 10px 20px;
    border: #fff 1px solid;
    margin: 15px 7px;
    border-radius: 4px;
    opacity: 0;
    animation-name: btn;
    animation-duration: 2s;
    animation-delay: 1s;
    animation-fill-mode: forwards;
  }
  
  @keyframes btn {
    0% {
      opacity: 0
    }
    100% {
      opacity: 1
    }
  }
  
  .button:hover {
    background-color: #fff;
    color: #58b038;
    text-decoration: none;
    transition: all 0.5s ease;
  }</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div id="section-1"&gt;
    &lt;header id="showcase"&gt;
      &lt;h1&gt;Showcase&lt;/h1&gt;
    &lt;/header&gt;
    &lt;img src="https://upload.wikimedia.org/wikipedia/commons/thumb/0/0d/Ski_trail_rating_symbol-blue_square.svg/600px-Ski_trail_rating_symbol-blue_square.svg.png" alt="Profile" id="showcase-img"&gt;
    &lt;div id="about" class="container"&gt;
      &lt;p&gt;Lorem ipsum dolor sit amet, consectetur adipisicing elit. Debitis natus maiores eum magni ab modi aspernatur quibusdam distinctio blanditiis nesciunt libero itaque, id, iure, quo.&lt;/p&gt;
      &lt;a href="#" target="_blank"&gt;&lt;i class="fa fa-github" aria-hidden="true"&gt;&lt;/i&gt;&lt;/a&gt;
      &lt;a href="#" target="_blank"&gt;&lt;i class="fa fa-linkedin-square" aria-hidden="true"&gt;&lt;/i&gt;&lt;/a&gt;
      &lt;a href="#"&gt;&lt;i class="fa fa-youtube" aria-hidden="true"&gt;&lt;/i&gt;&lt;/a&gt;
    &lt;/div&gt;
    &lt;a href="#" class="button"&gt;Button&lt;/a&gt;
    &lt;a href="#" class="button"&gt;Button&lt;/a&gt;
  &lt;/div&gt;
  &lt;!-- section-1 ends --&gt;</code></pre>
  </div>
  </div>
  </p>