.collapsible {
      background-color: #0070ad;
      color: white;
      cursor: pointer;
      padding: 18px;
      width: 100%;
      border: none;
      text-align: left;
      outline: none;
      font-size: 15px;
    }
    .content {
      padding: 0 18px;
      display: none;
      overflow: hidden;
      background-image: url('');
      background-repeat: no-repeat;
      background-attachment: fixed;
      background-size: cover;
    }

.active, .collapsible:hover {
  background-color: #0070ad;
}