studio - small display tweaks to setting form new/remove actions

cms/static/sass/_settings.scss

@@ -263,6 +263,12 @@ body.course.settings {
       .current {
         @include size(640px,362px);
       }
+
+      .actions {
+        margin-top: ($baseline/2);
+        border-top: 1px solid $gray-l5;
+        padding-top: ($baseline/2);
+      }
     }
 
     // specific fields - requirements

cms/templates/settings.html

@@ -167,7 +167,7 @@ from contentstore import utils
               <label for="course-overview">Course Introduction Video</label>
               <div class="input input-existing">
                 <div class="current current-course-introduction-video">
-                  <iframe width="100%" height="" src="" frameborder="0" allowfullscreen></iframe>
+                  <iframe width="640" height="362" src="" frameborder="0" allowfullscreen></iframe>
 
                 </div>
                 <div class="actions">