Fix alignment of "Remove Group" in admin edit option groups. refs #1679

@@ -1351,9 +1351,11 @@ h6.fieldset-heading {
 }
 
 .option-groups-region .accordion-header {
+    -moz-box-sizing: border-box;
+    box-sizing:      border-box;
     overflow:        hidden;
     display:         block;
-    width:      96%;
+    width:           98%;
     cursor:          move;
     margin-top:      0 !important;
     padding:         10px;