body {
      font-family: Arial, sans-serif;
      margin: 40px auto;
      max-width: 1000px; /* 桌面端宽度限制 */
      line-height: 1.6;
      color: #333;
      background: #f9fafb;
    }
    h1 {
      margin-bottom: 5px;
      color: #0b132b;
    }
    .subtitle {
      font-size: 15px;
      color: #555;
      margin: 2px 0;
    }
    .email {
      font-size: 14px;
      color: #777;
      margin: 2px 0 10px 0;
    }
    .address {
      font-size: 14px;
      color: #777;
      margin: 2px 0;
    }
    a {
      color: #0b5fa5;
      text-decoration: none;
    }
    a:hover {
      text-decoration: underline;
      color: #004080;
    }
    h2 {
      border-bottom: 2px solid #ccc;
      padding-bottom: 4px;
      color: #0b132b;
    }
    ul, ol { padding-left: 20px; }
    footer {
      margin-top: 40px;
      font-size: 13px;
      color: #777;
      text-align: center;
    }

    /* 目录样式 */
    nav ul {
      list-style: none;
      padding: 0;
      margin: 0;
    }
    nav ul li {
      margin: 8px 0;
    }
    nav ul li a {
      font-size: 14px;
      color: #0b5fa5;
      text-decoration: none;
    }
    nav ul li a:hover {
      text-decoration: underline;
      color: #004080;
    }
    /* header 两栏布局 */
    header {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
    }
    nav {
      margin-top: 20px; /* 往下调一点 */
    }
/* 平板竖屏：上下分布 */
@media (max-width: 992px) and (orientation: portrait) {
  body {
    margin: 0;
    padding: 0 30px;   /* 左右留白 */
    max-width: 100%;
  }
  header {
    flex-direction: column;
    align-items: flex-start;
  }
}

/* 平板设备：769px ~ 1024px，一律横向分布，留白 */
@media (min-width: 769px) and (max-width: 1024px) {
  body {
    margin: 0 auto;
    padding: 0 40px;   /* 平板左右留白 */
    max-width: 900px;  /* 控制内容宽度，避免贴边 */
  }
  header {
    flex-direction: row; /* 横向排列 */
    justify-content: space-between;
    align-items: flex-start;
  }
}



/* 手机竖屏：上下分布（≤768px） */
@media (max-width: 768px) and (orientation: portrait) {
  body {
    margin: 0;
    padding: 0 20px;
    max-width: 100%;
  }
  header {
    flex-direction: column;
    align-items: flex-start;
  }
  nav ul li a {
    font-size: 16px;
  }
}

/* 关键修正：横屏手机（高度较小）强制横向分布
   例：iPhone 14 Pro Max 横屏约 932×430，会命中这条 */
@media (orientation: landscape) and (max-height: 500px) {
  body {
    margin: 0;
    padding: 0 20px;
    max-width: 100%;
  }
  header {
    flex-direction: row;          /* 横向排列 */
    justify-content: space-between;
    align-items: flex-start;
  }
  nav ul li a {
    font-size: 14px;
  }
}

.return-wrap {
  text-align: right;
}

.return-btn {
  display: inline-block;
  font-size: 13px;
  color: #0b5fa5;
  text-decoration: none;
}

.return-btn:hover {
  text-decoration: underline;
  color: #004080;
}