/* 基础重置 */
      * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
      }

      /* 👉 【修改】让 HTML 和 BODY 撑满整个屏幕高度 */
      html {
        font-size: 16px;
        height: 100%;
      }

      /* 👉 【修改】将 body 设为垂直 Flex 布局，确保可以控制子元素高度的分配 */
      body {
        font-family: "Noto Sans SC", "微软雅黑", sans-serif;
        line-height: 1.5;
        color: #333;
        -webkit-text-size-adjust: 100%;
        -moz-text-size-adjust: 100%;
        -ms-text-size-adjust: 100%;
        text-size-adjust: 100%;
        background: #f8f9fa;
        height: 100%;        /* 撑满高度 */
        display: flex;       /* 开启 Flex 布局 */
        flex-direction: column; /* 让页面元素从上往下排 */
      }

      /* 👉 【新增】页面主要内容区域。它会自动拉伸，把页脚顶到最下面 */
      /* 提示：请确保你 HTML 里的主要内容用 <main> 包裹，或者在外层加上 class="main-content" */
      main, .main-content {
        flex: 1 0 auto; /* 1 代表自动拉伸撑满剩余空间，0 代表空间不足时不缩小，auto 为基础大小 */
      }

      .container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 15px;
      }

      /* 导航样式 */
      .navbar {
        background: #667eea;
        padding: 12px 0;
        position: sticky;
        top: 0;
        z-index: 1000;
      }

      .navbar .container {
        display: flex;
        justify-content: space-between;
        align-items: center;
      }

      .logo {
        font-size: 1.2rem;
        font-weight: bold;
        color: white;
        display: flex;
        align-items: center;
        gap: 8px;
      }

      .nav-links {
        display: flex;
        gap: 12px;
        flex-wrap: wrap;
      }

      .nav-links a {
        color: white;
        text-decoration: none;
        font-size: 0.9rem;
        padding: 5px 10px;
        border-radius: 5px;
      }

      .nav-links a:hover,
      .nav-links a.active {
        background: rgba(255, 255, 255, 0.2);
      }

      /* 面包屑导航 */
      .breadcrumb {
        background: #f5f5f5;
        padding: 12px 0;
        font-size: 0.85rem;
      }

      .breadcrumb a {
        color: #667eea;
        text-decoration: none;
      }

      .breadcrumb a:hover {
        text-decoration: underline;
      }

      /* 术语详情页头 */
      .term-header {
        background: linear-gradient(135deg,
            rgba(102, 126, 234, 0.9) 0%,
            rgba(118, 75, 162, 0.9) 100%);
        color: white;
        padding: 30px 0;
        margin-bottom: 30px;
        text-align: center;
        border-radius: 10px;
      }

      .term-header h1 {
        font-size: 2.2rem;
        margin-bottom: 15px;
        text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.2);
      }

      .term-header .term-origin {
        font-size: 1rem;
        background: rgba(255, 255, 255, 0.2);
        padding: 8px 15px;
        border-radius: 20px;
        display: inline-block;
      }

      /* 多语言表述 */
      .language-expressions {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 15px;
        margin-bottom: 30px;
      }

      .language-card {
        background: #f9f9f9;
        border-radius: 10px;
        padding: 20px;
        box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
        text-align: center;
      }

      .language-card h3 {
        font-size: 1.3rem;
        margin-bottom: 12px;
        color: #667eea;
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 8px;
      }

      .language-card .expression {
        font-size: 1.1rem;
        font-weight: bold;
        margin: 10px 0;
        padding: 8px;
        background: white;
        border-radius: 8px;
      }

      .language-card .pronunciation {
        color: #666;
        font-size: 0.9rem;
        margin-top: 5px;
      }

      /* 内容区域 */
      .content-section {
        margin-bottom: 40px;
      }

      .content-section h2 {
        font-size: 1.7rem;
        margin-bottom: 15px;
        color: #333;
        border-bottom: 2px solid #667eea;
        padding-bottom: 8px;
      }

      .content-section p {
        font-size: 0.95rem;
        color: #555;
        margin-bottom: 15px;
      }

      .content-section ul,
      .content-section ol {
        margin-left: 20px;
        margin-bottom: 15px;
      }

      .content-section li {
        margin-bottom: 8px;
        font-size: 0.95rem;
      }

      /* 图片展示区 */
      .image-gallery {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 20px;
        margin-bottom: 30px;
      }

      .image-item {
        background: #f9f9f9;
        border-radius: 10px;
        overflow: hidden;
        box-shadow: 0 3px 10px rgba(0, 0, 0, 0.1);
        transition: transform 0.3s ease;
      }

      .image-item:hover {
        transform: translateY(-5px);
      }

      .image-item img {
        width: 100%;
        height: 200px;
        object-fit: cover;
        display: block;
        }

      .image-caption {
        padding: 15px;
        font-size: 0.9rem;
        color: #666;
        text-align: center;
      }

      /* 相关技术 */
      .related-techniques {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
        gap: 15px;
        margin-bottom: 30px;
      }

      .related-card {
        background: #f9f9f9;
        border-radius: 10px;
        padding: 15px;
        text-align: center;
        text-decoration: none;
        color: #333;
        box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
        transition: all 0.3s ease;
      }

      .related-card:hover {
        background: #667eea;
        color: white;
        transform: translateY(-5px);
      }

      .related-card h4 {
        font-size: 1.1rem;
        margin-bottom: 5px;
      }

      /* 返回按钮 */
      .back-button {
        display: inline-block;
        background: #667eea;
        color: white;
        text-decoration: none;
        padding: 10px 20px;
        border-radius: 25px;
        font-weight: 500;
        margin: 20px 0;
        transition: all 0.3s ease;
      }

      .back-button:hover {
        background: #5a6fd8;
        transform: translateX(-3px);
      }

      /* 👉 【修改】页脚样式优化 */
      .footer {
        background: #333;
        color: white;
        text-align: center;
        padding: 25px 0;
        /* margin-top: 40px; */ /* 移除固定的外边距，交给 flex 自动顶开 */
        flex-shrink: 0;          /* 防止页脚在空间不足时被无情挤压变形 */
      }

      .footer-links {
        display: flex;
        justify-content: center;
        gap: 20px;
        margin-bottom: 15px;
        flex-wrap: wrap;
      }

      .footer-links a {
        color: #ddd;
        text-decoration: none;
        font-size: 0.9rem;
      }

      .footer-links a:hover {
        color: white;
        text-decoration: underline;
      }

      .footer p {
        font-size: 0.9rem;
        margin-top: 10px;
      }

      /* 社交媒体关注区样式 */
      .social-media-section {
        padding: 10px 0;
        background: linear-gradient(135deg, #f9f9f9 0%, #f0f0f0 100%);
        margin: 10px 0;
        border-radius: 12px;
      }

      .section-title {
        text-align: center;
        font-size: 2rem;
        color: #667eea;
      }

      .section-subtitle {
        text-align:left;
        color: #666;
        margin-bottom: 40px;
        margin-left: 20px;
        margin-right: 20px;
        font-size: 1.1rem;
      }

      .social-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 40px;
        max-width: 900px;
        margin: 0 auto;
      }

      .social-category {
        background: white;
        padding: 25px;
        border-radius: 12px;
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
      }

      .social-category h3 {
        font-size: 1.4rem;
        color: #333;
        margin-bottom: 20px;
        display: flex;
        align-items: center;
        gap: 10px;
      }

      .social-buttons {
        display: flex;
        flex-direction: column;
        gap: 15px;
      }

      .social-btn {
        display: flex;
        align-items: center;
        gap: 15px;
        padding: 15px 20px;
        border-radius: 8px;
        text-decoration: none;
        color: white;
        font-weight: 500;
        transition: all 0.3s ease;
        border: none;
        cursor: pointer;
        font-size: 1rem;
      }

      .social-btn i {
        font-size: 1.3rem;
      }

      .social-btn:hover {
        transform: translateY(-3px);
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.15);
      }

      /* 各平台按钮颜色 */
      .instagram {
        background: linear-gradient(45deg, #405de6, #833ab4, #fd1d1d);
      }

      .twitter {
        background: linear-gradient(45deg, #1da1f2, #14171a);
      }

      .telegram {
        background: linear-gradient(45deg, #0088cc, #2aabee);
      }

      .weibo {
        background: linear-gradient(45deg, #e6162d, #d81e06);
      }

      .qq {
        background: linear-gradient(45deg, #12b7f5, #1f9be0);
      }

      .wechat {
        background: linear-gradient(45deg, #07c160, #09bb07);
      }

      /* 弹窗样式 */
      .modal {
        display: none;
        position: fixed;
        z-index: 1000;
        left: 0;
        top: 0;
        width: 100%;
        height: 100%;
        background-color: rgba(0, 0, 0, 0.7);
      }

      .modal-content {
        background-color: white;
        margin: 10% auto;
        padding: 30px;
        border-radius: 12px;
        width: 90%;
        max-width: 400px;
        position: relative;
        text-align: center;
      }

      .close {
        color: #aaa;
        float: right;
        font-size: 28px;
        font-weight: bold;
        position: absolute;
        right: 20px;
        top: 10px;
        cursor: pointer;
      }

      .close:hover {
        color: #333;
      }

      .qr-container {
        margin: 25px 0;
        padding: 20px;
        background: #f9f9f9;
        border-radius: 8px;
        display: inline-block;
      }

      .qr-code {
        width: 200px;
        height: 200px;
        border-radius: 6px;
      }

      .qr-tip {
        color: #333;
        margin: 15px 0;
        font-size: 1.1rem;
      }

      .qr-tip-small {
        color: #666;
        font-size: 0.9rem;
        margin-top: 10px;
      }

      /* 响应式调整 */
      @media (max-width: 992px) {
        html {
          font-size: 15px;
        }

        .term-header h1 {
          font-size: 2rem;
        }

        .language-expressions {
          grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        }

        .image-gallery {
          grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        }
      }

      @media (max-width: 768px) {
        html {
          font-size: 15px;
        }

        .term-header {
          padding: 25px 0;
        }

        .term-header h1 {
          font-size: 1.6rem;
        }

        .language-expressions {
          grid-template-columns: 1fr;
          gap: 12px;
        }

        .language-card {
          padding: 15px;
        }

        .language-card h3 {
          font-size: 1.1rem;
        }

        .content-section h2 {
          font-size: 1.5rem;
        }

        .image-gallery {
          grid-template-columns: 1fr;
          gap: 15px;
        }

        .image-item img {
          height: 180px;
        }

        .related-techniques {
          grid-template-columns: repeat(2, 1fr);
        }

        .navbar .container {
          flex-direction: column;
          gap: 10px;
        }

        .nav-links {
          gap: 8px;
        }

        .nav-links a {
          font-size: 0.85rem;
          padding: 4px 8px;
        }

        .logo {
          font-size: 1.1rem;
        }

        .social-grid {
          grid-template-columns: 1fr;
          gap: 25px;
        }

        .social-category {
          padding: 20px;
        }

        .modal-content {
          margin: 20% auto;
          width: 95%;
          padding: 25px;
        }
      }

      @media (max-width: 576px) {
        html {
          font-size: 13px;
        }

        .term-header h1 {
          font-size: 1.6rem;
          padding: 0 10px;
        }

        .content-section h2 {
          font-size: 1.4rem;
        }

        .image-item img {
          height: 160px;
        }

        .related-techniques {
          grid-template-columns: 1fr;
        }

        .nav-links a {
          font-size: 0.8rem;
          padding: 3px 6px;
        }

        .container {
          padding: 0 10px;
        }

        .footer-links {
          gap: 15px;
        }
      }

      @media (max-width: 360px) {
        html {
          font-size: 13px;
        }

        .term-header h1 {
          font-size: 1.4rem;
        }

        .nav-links {
          align-items: center;
        }

        .nav-links a {
          font-size: 0.85rem;
        }
      }