/* Loading overlay backdrop */
.sidebar {
  z-index: 10000; /* มากกว่า backdrop */
}
    #loading-backdrop {
      position: fixed;
      top: 0; left: 0;
      width: 100vw;
      height: 100vh;
      background-color: rgba(255, 255, 255, 0.9);
      z-index: 9999;
      display: flex;
      align-items: center;
      justify-content: center;
      flex-direction: column;
    }

    #main-content {
      display: none;
    }

    .fade-out {
      opacity: 0;
      transition: opacity 0.2s ease-out;
    }