title: how to change css img element with javascript
body: <p>I would like to change the CSS using javascript so that I can dynamically adjust the height of a single image on my web page. This is being done so that the image will fit nicely in the viewable screen no matter what the screen size. </p>
  
  <p>My CSS</p>
  
  <pre><code>.wrapper img {
  height: 630px;
  }
  </code></pre>
  
  <p>My Div</p>
  
  <pre><code>&lt;div class="wrapper" id="imageDiv"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>What javascript code should I use to change the CSS height to say 200px.</p>
  
  <p>Thank you.</p>