message: flat button style
diff: @@ -393,9 +393,10 @@ svg#pointers line {
  }
  #download a, #download button {
  - background-color: #f9f9f9;
  - border: 1px solid #ddd;
  - color: #555;
  + background-color: #ddd;
  + border: 0;
  + color: #333;
  + cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  display: inline-block;
  