table {
    width: 100%;
    border-collapse: collapse;
  }

  th, td {
    padding: 8px;
    border: 1px solid #ccc;
    text-align: center;
  }

  .flash-up {
    background-color: lightgreen;
    color: white;
    animation: flash 0.5s;
  }

  .flash-down {
    background-color: pink;
    color: white;
    animation: flash 0.5s;
  }

  @keyframes flash {
    0% { opacity: 1; }
    50% { opacity: 0.6; }
    100% { opacity: 1; }
  }