title: offsetTop returns the wrong value
body: <p>I need to get the offsetTop of an alement that does not have an ID so I am getting the selectors by name:</p>
  
  <pre><code>const element = document.getElementsByTagName('bs-datepicker-container');
  </code></pre>
  
  <p>and then if I where to console.log <code>element</code> I can see the offset top is -55 which is correct, the element is off the screen by approximately 55 pixels.</p>
  
  <p>however when I specifically target the element as follows:</p>
  
  <pre><code>console.log(element['0'].offsetTop);
  </code></pre>
  
  <p>I suddenly see an output of 949. considering my screen size is 1080 this would mean the offsetTop was almost at the bottom of my screen which it is not.</p>