update video thumbnail and styles

app/styles/components/user-guide.scss

@@ -1,9 +1,10 @@
 .help-video
 {
-  max-width: 90%;
+  max-width: 100%;
   height: auto;
   max-height: 75%;
-  text-align:center;
+  text-align: center;
+  cursor: pointer;
 }
 
 .help-img {

app/templates/user-guide.hbs

@@ -8,7 +8,7 @@
   <p>(Click the image to open large in a new tab.)</p>
   <a href="/assets/images/btr-help-image.jpg" target="_blank"><img src="/assets/images/btr-help-image.jpg" class="help-img img-fluid"></a>
 
-  <h3 class="mt-4">Video tutorial</h3>
+  <h3 class="mt-5 mb-3">Video tutorial</h3>
     <video controls="controls" src="/assets/videos/btr_getting_started.mp4" class="help-video" poster="/assets/images/vid-thumb.jpg">
     Your browser does not support the HTML5 Video element.
     </video>