Make rubric cleaner and visually simpler

lms/static/sass/course/_rubric.scss

 .rubric {
-  padding: 40px 0px;
+  margin: 40px 0px;
   tr {
       margin:10px 0px;
       height: 100%;
@@ -8,6 +8,7 @@
       padding: 20px 0px 25px 0px;
       height: 100%;
       border: 1px black solid;
+      text-align: center;
   }
   th {
       padding: 5px;
@@ -17,13 +18,11 @@
   .points-header th {
       padding: 0px;
   }
-  label,
-  .view-only {
-      margin:2px;
+  .rubric-label
+  {
       position: relative;
-      padding: 15px 15px 25px 15px;
+      padding: 15px 15px 25px;
       width: 130px;
-      height:100%;
       min-height: 50px;
       min-width: 50px;
       font-size: .9em;
@@ -40,9 +39,9 @@
     background: #666;
     color: white; 
   }
-  input[type=radio]:checked + label {
-    background: #666;
-    color: white; }
+   input[type=radio]:checked + .rubric-label {
+    background: white;
+    color: $base-font-color; }
   input[class='score-selection'] {
       position: relative;
       margin-left: 10px;

lms/templates/open_ended_rubric.html

@@ -26,15 +26,15 @@
                 % if view_only:
                     ## if this is the selected rubric block, show it highlighted
                     % if option['selected']:
-                        <div class="view-only selected-grade">
+                        <div class="rubric-label selected-grade">
                     % else:
-                        <div class="view-only">
+                        <div class="rubric-label">
                     % endif
                         ${option['text']}
                         </div>
                 % else:
                     <input type="radio" class="score-selection" name="score-selection-${i}" id="score-${i}-${j}" value="${option['points']}"/>
-                    <label for="score-${i}-${j}">${option['text']}</label>
+                    <label class="rubric-label" for="score-${i}-${j}">${option['text']}</label>
                 % endif
             </td>
             % endfor