/* 页面特定样式 */
    :root {
      --ai-blue: #2563eb;
      --ai-blue-light: #3b82f6;
      --ai-purple: #7c3aed;
      --ai-gradient: linear-gradient(135deg, var(--ai-blue), var(--ai-purple));
      --text-dark: #1e293b;
      --text-gray: #64748b;
      --bg-light: #f8fafc;
      --card-bg: #ffffff;
      --border: #e2e8f0;
    }
    
    /* ========== 导航栏边框强制移除 ========== */
    .navbar,
    .navbar-light,
    .navbar-expand-lg,
    .navbar-brand,
    .nav-link,
    .nav-item,
    .navbar-nav,
    .navbar-collapse {
      border: none !important;
      border-top: none !important;
      border-bottom: none !important;
      outline: none !important;
    }
    
    /* 悬停状态边框移除 */
    .navbar-brand:hover,
    .navbar-brand:focus,
    .nav-link:hover,
    .nav-link:focus,
    .nav-link:active,
    .nav-item:hover,
    .nav-item:focus {
      border: none !important;
      outline: none !important;
      box-shadow: none !important;
      background: transparent !important;
      color: var(--text-dark) !important;
    }
    
    /* 移除Bootstrap默认的padding和margin */
    .navbar-brand {
      padding: 0 !important;
      margin-right: 0 !important;
    }
    
    .nav-item {
      margin: 0 !important;
      padding: 0 !important;
    }

    /* ========== 页面头部横幅 ========== */
    .page-hero {
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      padding: 80px 0 100px;
      margin-bottom: -40px;
      position: relative;
      overflow: hidden;
    }
    .page-hero::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
      opacity: 0.4;
    }
    .page-hero .container {
      position: relative;
      z-index: 1;
    }
    .page-header {
      text-align: center;
      color: white;
    }
    .page-header h1 {
      font-size: 3.5rem;
      font-weight: 900;
      color: white;
      margin-bottom: 20px;
      letter-spacing: -1px;
      text-shadow: 0 4px 20px rgba(0,0,0,0.2);
      animation: fadeInDown 0.8s ease-out;
    }
    .page-header p {
      color: rgba(255,255,255,0.95);
      max-width: 800px;
      margin: 0 auto 40px;
      font-size: 1.25rem;
      line-height: 1.8;
      animation: fadeInUp 0.8s ease-out 0.2s backwards;
    }

    /* ========== 搜索栏 ========== */
    .search-container {
      max-width: 600px;
      margin: 0 auto;
      animation: fadeInUp 0.8s ease-out 0.4s backwards;
    }
    .search-box {
      display: flex;
      background: rgba(255,255,255,0.95);
      border-radius: 50px;
      padding: 8px 8px 8px 28px;
      box-shadow: 0 8px 32px rgba(0,0,0,0.12);
      transition: all 0.3s ease;
    }
    .search-box:focus-within {
      background: white;
      box-shadow: 0 12px 48px rgba(0,0,0,0.2);
      transform: translateY(-2px);
    }
    .search-box input {
      flex: 1;
      border: none;
      outline: none;
      background: transparent;
      font-size: 1.05rem;
      padding: 8px 12px;
      color: var(--text-dark);
    }
    .search-box input::placeholder {
      color: var(--text-gray);
    }
    .search-box button {
      background: var(--ai-gradient);
      border: none;
      color: white;
      padding: 12px 32px;
      border-radius: 50px;
      font-weight: 600;
      cursor: pointer;
      transition: all 0.3s ease;
      white-space: nowrap;
    }
    .search-box button:hover {
      transform: scale(1.05);
      box-shadow: 0 4px 16px rgba(37,99,235,0.4);
    }

    /* ========== 统计信息 ========== */
    .stats-bar {
      background: white;
      border-radius: 20px;
      box-shadow: 0 10px 40px rgba(0,0,0,0.08);
      padding: 32px 48px;
      margin: 60px 0 50px;
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 40px;
      animation: fadeInUp 0.8s ease-out 0.6s backwards;
    }
    .stat-item {
      text-align: center;
      position: relative;
    }
    .stat-item:not(:last-child)::after {
      content: '';
      position: absolute;
      right: -20px;
      top: 50%;
      transform: translateY(-50%);
      width: 2px;
      height: 60%;
      background: var(--border);
    }
    .stat-icon {
      font-size: 2.5rem;
      margin-bottom: 12px;
      display: block;
    }
    .stat-number {
      font-size: 2rem;
      font-weight: 800;
      background: var(--ai-gradient);
      -webkit-background-clip: text;
      background-clip: text;
      color: transparent;
      display: block;
      margin-bottom: 8px;
    }
    .stat-label {
      color: var(--text-gray);
      font-size: 0.95rem;
      font-weight: 600;
    }

    /* ========== 分类标签栏 ========== */
    .category-filter {
      display: flex;
      gap: 12px;
      flex-wrap: wrap;
      justify-content: center;
      margin-bottom: 50px;
      animation: fadeInUp 0.8s ease-out 0.8s backwards;
    }
    .category-tag {
      background: white;
      border: 2px solid var(--border);
      padding: 10px 24px;
      border-radius: 50px;
      font-weight: 600;
      cursor: pointer;
      transition: all 0.3s ease;
      font-size: 0.95rem;
      color: var(--text-dark);
    }
    .category-tag:hover,
    .category-tag.active {
      background: var(--ai-gradient);
      border-color: transparent;
      color: white;
      transform: translateY(-2px);
      box-shadow: 0 4px 16px rgba(37,99,235,0.3);
    }
    .category-tag .badge {
      background: rgba(0,0,0,0.1);
      padding: 2px 8px;
      border-radius: 10px;
      font-size: 0.8rem;
      margin-left: 6px;
    }
    .category-tag.active .badge {
      background: rgba(255,255,255,0.3);
    }

    /* ========== 内容区域标题 ========== */
    .section-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin-bottom: 30px;
      animation: fadeInUp 0.8s ease-out 1s backwards;
    }
    .section-title {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--text-dark);
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .section-title::before {
      content: '';
      width: 6px;
      height: 32px;
      background: var(--ai-gradient);
      border-radius: 3px;
    }
    .view-mode {
      display: flex;
      gap: 8px;
      background: white;
      padding: 6px;
      border-radius: 12px;
      border: 2px solid var(--border);
    }
    .view-btn {
      padding: 8px 16px;
      border: none;
      background: transparent;
      border-radius: 8px;
      cursor: pointer;
      font-size: 1.2rem;
      transition: all 0.2s ease;
      color: var(--text-gray);
    }
    .view-btn:hover,
    .view-btn.active {
      background: var(--ai-gradient);
      color: white;
    }

    /* ========== 文章卡片 - 增强版 ========== */
    .article-card {
      background: var(--card-bg);
      border-radius: 24px;
      overflow: hidden;
      height: 100%;
      box-shadow: 0 4px 20px rgba(0,0,0,0.08);
      border: 2px solid transparent;
      transition: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
      position: relative;
      display: flex;
      flex-direction: column;
    }
    .article-card a {
      text-decoration: none;
      color: inherit;
    }
    .article-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 6px;
      background: var(--ai-gradient);
      transform: scaleX(0);
      transform-origin: left;
      transition: transform 0.5s ease;
      pointer-events: none;
      z-index: 1;
    }
    .article-card::after {
      content: '';
      position: absolute;
      inset: 0;
      border-radius: 24px;
      padding: 2px;
      background: var(--ai-gradient);
      -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
      -webkit-mask-composite: xor;
      mask-composite: exclude;
      opacity: 0;
      transition: opacity 0.5s ease;
      pointer-events: none;
      z-index: 0;
    }
    .article-card:hover {
      transform: translateY(-12px) scale(1.02);
      box-shadow: 0 20px 60px rgba(37, 99, 235, 0.2);
      border-color: transparent;
    }
    .article-card:hover::before {
      transform: scaleX(1);
    }
    .article-card:hover::after {
      opacity: 1;
    }

    /* 文章分类标签 */
    .card-category {
      position: absolute;
      top: 20px;
      right: 20px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(10px);
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 0.85rem;
      font-weight: 700;
      color: var(--ai-blue);
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
      z-index: 10;
      transition: all 0.3s ease;
      pointer-events: none;
    }
    .article-card:hover .card-category {
      background: var(--ai-gradient);
      color: white;
      transform: scale(1.1);
    }

    /* 文章缩略图区域 */
    .card-thumbnail {
      height: 220px;
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      cursor: pointer;
      transition: all 0.5s ease;
    }
    .card-thumbnail:hover {
      background: linear-gradient(135deg, #764ba2 0%, #667eea 100%);
    }
    .card-thumbnail::before {
      content: '';
      position: absolute;
      inset: 0;
      background: url("data:image/svg+xml,%3Csvg width='100' height='100' viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M11 18c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm48 25c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm-43-7c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm63 31c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM34 90c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm56-76c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM12 86c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm28-65c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm23-11c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-6 60c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm29 22c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zM32 63c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm57-13c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-9-21c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM60 91c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM35 41c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM12 60c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2z' fill='%23ffffff' fill-opacity='0.08' fill-rule='evenodd'/%3E%3C/svg%3E");
      opacity: 0.5;
      pointer-events: none;
      z-index: 0;
    }
    .card-thumbnail-icon {
      font-size: 5rem;
      opacity: 0.9;
      transition: all 0.5s ease;
      position: relative;
      z-index: 1;
      pointer-events: none;
    }
    .article-card:hover .card-thumbnail-icon {
      transform: scale(1.2) rotate(5deg);
      opacity: 1;
    }

    /* 卡片内容区域 */
    .card-body {
      padding: 32px;
      position: relative;
      flex: 1;
      display: flex;
      flex-direction: column;
      z-index: 2;
    }
    .card-title {
      font-size: 1.5rem;
      font-weight: 800;
      margin-bottom: 16px;
      color: var(--text-dark);
      line-height: 1.4;
      display: -webkit-box;
      -webkit-line-clamp: 2;
      -webkit-box-orient: vertical;
      overflow: hidden;
      transition: all 0.3s ease;
      position: relative;
      cursor: pointer;
      z-index: 3;
    }
    .card-title a {
      color: inherit;
      text-decoration: none;
      cursor: pointer;
      position: relative;
      z-index: 3;
    }
    .card-title::before {
      content: '';
      position: absolute;
      left: 0;
      bottom: -4px;
      width: 0;
      height: 3px;
      background: var(--ai-gradient);
      transition: width 0.3s ease;
    }
    .article-card:hover .card-title {
      color: var(--ai-blue);
    }
    .article-card:hover .card-title::before {
      width: 60px;
    }
    .card-text {
      color: var(--text-gray);
      margin-bottom: 24px;
      line-height: 1.9;
      display: -webkit-box;
      -webkit-line-clamp: 3;
      -webkit-box-orient: vertical;
      overflow: hidden;
      font-size: 1rem;
      flex: 1;
    }

    /* 卡片底部 */
    .card-footer-custom {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding-top: 20px;
      border-top: 2px solid var(--border);
      margin-top: auto;
      position: relative;
      z-index: 3;
    }
    .card-meta-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .card-meta-item {
      display: flex;
      align-items: center;
      gap: 6px;
      color: var(--text-gray);
      font-size: 0.9rem;
      font-weight: 500;
    }
    .meta-icon {
      font-size: 1.1rem;
    }
    .btn-read {
      background: var(--ai-gradient);
      border: none;
      padding: 10px 28px;
      font-weight: 700;
      border-radius: 12px;
      font-size: 0.95rem;
      transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.4s ease;
      position: relative;
      overflow: hidden;
      color: white !important;
      text-decoration: none !important;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
      cursor: pointer !important;
      user-select: none;
      z-index: 10;
    }
    .btn-read * {
      cursor: pointer !important;
      color: white !important;
      text-decoration: none !important;
    }
    .btn-read::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 0;
      height: 0;
      border-radius: 50%;
      background: rgba(255,255,255,0.25);
      transform: translate(-50%, -50%);
      transition: width 0.5s ease, height 0.5s ease;
      pointer-events: none;
      z-index: 0;
    }
    .btn-read:hover::before {
      width: 300px;
      height: 300px;
    }
    .btn-read::after {
      content: '→';
      font-size: 1.2rem;
      transition: transform 0.4s ease;
      position: relative;
      z-index: 2;
      pointer-events: none;
    }
    .btn-read span {
      position: relative;
      z-index: 2;
      pointer-events: none;
    }
    .btn-read:hover,
    .btn-read:focus,
    .btn-read:active,
    .btn-read:visited {
      transform: translateX(4px) scale(1.05);
      box-shadow: 0 8px 24px rgba(37, 99, 235, 0.5);
      color: white !important;
      text-decoration: none !important;
      cursor: pointer !important;
    }
    .btn-read:hover::after {
      transform: translateX(4px);
    }

    /* ========== 空状态 ========== */
    .empty-state {
      text-align: center;
      padding: 80px 20px;
      background: white;
      border-radius: 20px;
      box-shadow: 0 8px 24px rgba(0,0,0,0.06);
      max-width: 500px;
      margin: 0 auto;
    }
    .empty-state .icon {
      font-size: 4rem;
      margin-bottom: 20px;
      opacity: 0.3;
    }
    .empty-state h5 {
      font-size: 1.3rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 12px;
    }
    .empty-state p {
      color: var(--text-gray);
      font-size: 1rem;
    }

    /* ========== 文章网格动画 ========== */
    .article-card {
      animation: fadeInUp 0.8s ease-out backwards;
    }
    .article-card:nth-child(1) { animation-delay: 0.1s; }
    .article-card:nth-child(2) { animation-delay: 0.2s; }
    .article-card:nth-child(3) { animation-delay: 0.3s; }
    .article-card:nth-child(4) { animation-delay: 0.4s; }
    .article-card:nth-child(5) { animation-delay: 0.5s; }
    .article-card:nth-child(6) { animation-delay: 0.6s; }
    .article-card:nth-child(7) { animation-delay: 0.7s; }
    .article-card:nth-child(8) { animation-delay: 0.8s; }
    .article-card:nth-child(9) { animation-delay: 0.9s; }

    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(40px) scale(0.95);
      }
      to {
        opacity: 1;
        transform: translateY(0) scale(1);
      }
    }

    @keyframes fadeInDown {
      from {
        opacity: 0;
        transform: translateY(-40px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    /* ========== 响应式设计 ========== */
    @media (max-width: 992px) {
      .row-cols-lg-3 { 
        grid-template-columns: repeat(2, 1fr); 
      }
      .articles-grid {
        grid-template-columns: repeat(2, 1fr) !important;
      }
      .stats-bar {
        grid-template-columns: repeat(2, 1fr);
        gap: 30px;
        padding: 24px 32px;
      }
      .stat-item:nth-child(2)::after {
        display: none;
      }
      .section-header {
        flex-direction: column;
        gap: 20px;
        align-items: flex-start;
      }
    }

    @media (max-width: 768px) {
      .page-hero {
        padding: 60px 0 80px;
      }
      .page-header h1 { 
        font-size: 2.5rem; 
      }
      .page-header p {
        font-size: 1.05rem;
        margin-bottom: 30px;
      }
      .search-box {
        flex-direction: column;
        border-radius: 20px;
        padding: 16px;
      }
      .search-box button {
        width: 100%;
        border-radius: 12px;
      }
      /* 搜索框响应式样式 */
      .search-box-container {
        max-width: 100% !important;
        padding: 0 16px;
        box-sizing: border-box;
      }
      .search-box-inner {
        padding: 12px !important;
        flex-wrap: wrap;
      }
      .search-box-inner span {
        font-size: 1rem !important;
        padding: 0 12px !important;
      }
      .search-box-inner input {
        padding: 10px 6px !important;
        font-size: 0.95rem !important;
      }
      .search-box-inner button {
        padding: 10px 24px !important;
        font-size: 0.9rem !important;
        width: 100%;
        margin-top: 8px;
      }
      .stats-bar {
        grid-template-columns: 1fr;
        gap: 24px;
        padding: 24px;
      }
      .stat-item::after {
        display: none;
      }
      .category-filter {
        justify-content: flex-start;
        overflow-x: auto;
        flex-wrap: nowrap;
        padding-bottom: 10px;
      }
      .category-tag {
        white-space: nowrap;
      }
      .card-body { 
        padding: 24px; 
      }
      .card-title {
        font-size: 1.3rem;
      }
      .card-thumbnail {
        height: 180px;
      }
      .row-cols-md-2 {
        grid-template-columns: 1fr;
      }
      .articles-grid {
        grid-template-columns: 1fr !important;
      }
      main {
        padding-bottom: 60px;
      }
      .section-title {
        font-size: 1.5rem;
      }
    }

    @media (max-width: 576px) {
      .page-header h1 {
        font-size: 2rem;
      }
      .page-header p {
        font-size: 0.95rem;
      }
      .card-footer-custom {
        flex-direction: column;
        gap: 16px;
        align-items: flex-start;
      }
      .btn-read {
        width: 100%;
        justify-content: center;
      }
    }