title: Show/Hide div, with plain JS
body: <p>My CSS:</p>
  
  <pre><code>#a_x200{
      visibility: hidden;
      width: 200px;
      height: 200px;
      background-color: black;
  }
  </code></pre>
  
  <p>My JS:</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
      function show(id) {
          document.getElementById(id).style.display = 'block';
      }
  &lt;/script&gt;
  </code></pre>
  
  <p>My Html    </p>
  
  <pre><code>&lt;div id="a_x200"&gt;asd&lt;/div&gt;
  &lt;innput type="button" class="button_p_1" onclick="show('a_x200');"&gt;&lt;/input&gt;
  </code></pre>
  
  <p>Not working I think I missed something!</p>