/* Hidden by default */
  #rwx-lightbox {
    display: none;
    position: fixed;
    z-index: 9999;
    inset: 0;               /* shorthand for top/right/bottom/left: 0 */
    background: rgba(0,0,0,0.85);
    justify-content: center;
    align-items: center;
    padding: 2rem;
  }
  /* Visible state */
  #rwx-lightbox.open {
    display: flex;
  }
  #rwx-lightbox img {
    max-width: 90%;
    max-height: 85vh;
    border-radius: 6px;
    box-shadow: 0 0 15px rgba(0,0,0,0.6);
  }
  #rwx-close {
    position: absolute;
    top: 20px; right: 30px;
    color: #fff;
    background: transparent;
    border: 0;
    font-size: 36px;
    line-height: 1;
    cursor: pointer;
  }
  #rwx-close:hover { color: #ccc; }