.collapsible a img {
      border: none;
    }

    .collapsible {
      margin-top: 5px;
      border: 1px dashed #c0c0c0;
      padding: 3px;
    }    

    .collapsible a {
      color: #3465a4;
      text-decoration: none;
      font-weight: bold;
    }

    .collapsible>div{
      margin: 2px;
      padding: 6px;
    }

    img[src="twisty-down.gif"] {
      display: none;
    }