Style target notes for easy visual identification

app/assets/stylesheets/sections/notes.scss

 /**
  * Notes
  */
+
+@-webkit-keyframes target-note {
+  from { background:#fffff0; }
+  50% { background:#ffffd3; }
+  to { background:#fffff0; }
+}
+
 ul.notes {
   display: block;
   list-style: none;
@@ -91,6 +98,11 @@ ul.notes {
     }
   }
 
+  .note:target {
+    -webkit-animation:target-note 2s linear;
+    background: #fffff0;
+  }
+
   // paint top or bottom borders depending on notes direction
   &:not(.reversed) .note,
   &:not(.reversed) .discussion {