Fix CSS to fit all elements on the page

lms/static/sass/course/_staff_grading.scss

@@ -120,7 +120,7 @@ div.peer-grading{
         margin-right:20px;
         > div
         {
-            padding: 10px;
+            padding: 2px;
             margin: 0px;
             background: #eee;
             height: 10em;