body {
      margin: 0;
      padding: 0;
      font-family: sans-serif;
      background: url('arabic-night-background.png') no-repeat center center fixed;
      background-size: cover;
      position: relative;
    }
    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-color: rgba(0, 0, 0, 0.4);
      z-index: -1;
    }
    h1 {
      text-align: center;
      color: white;
      text-shadow: 1px 1px 4px #000;
      margin: 20px;
    }
    #grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
      gap: 15px;
      padding: 20px;
      max-width: 900px;
      margin: auto;
    }
    .card {
      perspective: 1000px;
      height: 100px;
    }
    .card-inner {
      position: relative;
      width: 100%;
      height: 100%;
      text-align: center;
      transition: transform 0.6s;
      transform-style: preserve-3d;
    }
    .card.flipped .card-inner {
      transform: rotateY(180deg);
    }
    .card-front, .card-back {
      position: absolute;
      width: 100%;
      height: 100%;
      border-radius: 10px;
      backface-visibility: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 2em;
      box-shadow: 2px 2px 10px rgba(0,0,0,0.3);
    }
    .card-front {
      background: rgba(255,255,255,0.9);
    }
    .card-back {
      background: #dff0d8;
      transform: rotateY(180deg);
    }
    #reset-btn {
      display: block;
      margin: 20px auto;
      padding: 10px 20px;
      font-size: 1em;
      cursor: pointer;
    }