h2 {
    text-align: center;
    font-size: 1.6rem;
    /* margin: 40px 0 20px 0; */
    padding: 10px 0;
    background-color: #e0f7fa;
    border-radius: 8px;
    color: #00796b;
    border: 1px solid #b2dfdb;
  }

  /* 自适应网格容器 */
  .grid-container {
    display: grid;
    gap: 20px;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    justify-items: center;
  }

  .box {
    background: #fff;
    border-radius: 12px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
    text-decoration: none;
    color: inherit;
    width: 100%;
    border: 1px solid #e0e0e0;
    box-sizing: border-box;
  }

  .box:hover {
    transform: translateY(-4px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
  }

  .box-title {
    font-size: 16px;
    font-weight: bold;
    margin-bottom: 5px;
  }

  .box-desc {
    font-size: 14px;
    color: #666;
  }

  /* 意见反馈按钮 */
  .feedback-btn {
    display: block;
    width: 200px;
    margin: 40px auto 20px auto;
    padding: 12px 20px;
    text-align: center;
    background-color: #00796b;
    color: #fff;
    font-size: 16px;
    font-weight: bold;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    text-decoration: none;
    transition: background-color 0.2s, transform 0.2s;
  }

  .feedback-btn:hover {
    background-color: #004d40;
    transform: translateY(-2px);
  }

  /* 手机端响应式: 2列, 如果单数最后一个自动占满 */
  @media (max-width: 768px) {
    .grid-container {
      grid-template-columns: repeat(2, 1fr);
    }
    .box {
      max-width: 95%;
    }
    /* 针对奇数最后一个Box占满一行 */
    .grid-container > .box:last-child:nth-child(odd) {
      grid-column: 1 / -1; /* 占满整行 */
    }
    .feedback-btn {
      width: 80%;
    }
  }