* {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
      }

      :root {
        --primary: #6366F1;
        --secondary: #EC4899;
        --accent: #14B8A6;
        --dark: #1F2937;
        --light: #F3F4F6;
        --white: #FFFFFF;
        --text-primary: #111827;
        --text-secondary: #6B7280;
        --border: #E5E7EB;
        --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
        --shadow-md: 0 4px 6px rgba(0,0,0,0.1);
        --shadow-lg: 0 10px 25px rgba(0,0,0,0.15);
        --gradient-primary: linear-gradient(135deg, #6366F1 0%, #8B5CF6 100%);
        --gradient-secondary: linear-gradient(135deg, #EC4899 0%, #F43F5E 100%);
        --gradient-accent: linear-gradient(135deg, #14B8A6 0%, #06B6D4 100%);
      }

      body {
        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
        color: var(--text-primary);
        line-height: 1.6;
        background: var(--light);
      }

      .header {
        background: var(--white);
        box-shadow: var(--shadow-sm);
        position: sticky;
        top: 0;
        z-index: 1000;
        border-bottom: 1px solid var(--border);
      }

      .header-container {
        max-width: 1400px;
        margin: 0 auto;
        padding: 1rem 2rem;
        display: flex;
        align-items: center;
        justify-content: space-between;
      }

      .logo {
        display: flex;
        align-items: center;
        gap: 0.75rem;
        font-size: 1.5rem;
        font-weight: 800;
        background: var(--gradient-primary);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        cursor: pointer;
      }

      .logo-icon {
        width: 40px;
        height: 40px;
        background: var(--gradient-primary);
        border-radius: 12px;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem;
      }

      .nav-menu {
        display: flex;
        gap: 2.5rem;
        align-items: center;
      }

      .nav-item {
        position: relative;
        color: var(--text-primary);
        text-decoration: none;
        font-weight: 600;
        font-size: 0.95rem;
        transition: color 0.3s;
        cursor: pointer;
      }

      .nav-item:hover,
      .nav-item.active {
        color: var(--primary);
      }

      .nav-item.active::after {
        content: '';
        position: absolute;
        bottom: -1.5rem;
        left: 0;
        right: 0;
        height: 3px;
        background: var(--gradient-primary);
        border-radius: 3px 3px 0 0;
      }

      .header-actions {
        display: flex;
        align-items: center;
        gap: 1rem;
      }

      .search-input {
        padding: 0.6rem 1.2rem;
        border: 2px solid var(--border);
        border-radius: 24px;
        outline: none;
        font-size: 0.9rem;
        width: 220px;
        transition: all 0.3s;
      }

      .search-input:focus {
        border-color: var(--primary);
        box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
      }

      .btn {
        padding: 0.6rem 1.5rem;
        border: none;
        border-radius: 24px;
        font-weight: 600;
        font-size: 0.9rem;
        cursor: pointer;
        transition: all 0.3s;
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
      }

      .btn-primary {
        background: var(--gradient-primary);
        color: white;
      }

      .btn-primary:hover {
        transform: translateY(-2px);
        box-shadow: var(--shadow-md);
      }

      .btn-outline {
        background: transparent;
        border: 2px solid var(--primary);
        color: var(--primary);
      }

      .btn-outline:hover {
        background: var(--primary);
        color: white;
      }

      .avatar {
        width: 38px;
        height: 38px;
        border-radius: 50%;
        background: var(--gradient-secondary);
        display: flex;
        align-items: center;
        justify-content: center;
        color: white;
        font-size: 1.2rem;
        cursor: pointer;
        transition: transform 0.3s;
      }

      .avatar:hover {
        transform: scale(1.1);
      }

      .container {
        max-width: 1400px;
        margin: 0 auto;
        padding: 2rem;
      }

      .page {
        display: none;
      }

      .page.active {
        display: block;
      }

      .hero {
        text-align: center;
        padding: 4rem 0;
        background: linear-gradient(135deg, rgba(99, 102, 241, 0.05) 0%, rgba(139, 92, 246, 0.05) 100%);
        border-radius: 24px;
        margin-bottom: 3rem;
      }

      .hero h1 {
        font-size: 3.5rem;
        font-weight: 900;
        margin-bottom: 1rem;
        background: var(--gradient-primary);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
      }

      .hero p {
        font-size: 1.3rem;
        color: var(--text-secondary);
        margin-bottom: 2rem;
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
      }

      .hero-actions {
        display: flex;
        gap: 1rem;
        justify-content: center;
        flex-wrap: wrap;
      }

      .hero .btn {
        padding: 1rem 2.5rem;
        font-size: 1.1rem;
      }

      .section-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin-bottom: 2rem;
      }

      .section-title {
        font-size: 2rem;
        font-weight: 800;
        color: var(--text-primary);
      }

      .view-more {
        color: var(--primary);
        text-decoration: none;
        font-weight: 600;
        display: flex;
        align-items: center;
        gap: 0.5rem;
        transition: gap 0.3s;
      }

      .view-more:hover {
        gap: 0.75rem;
      }

      .tabs {
        display: flex;
        gap: 1rem;
        margin-bottom: 2rem;
        border-bottom: 2px solid var(--border);
        overflow-x: auto;
        padding-bottom: 0.5rem;
      }

      .tab {
        padding: 0.75rem 1.5rem;
        background: transparent;
        border: none;
        color: var(--text-secondary);
        font-weight: 600;
        cursor: pointer;
        border-radius: 12px 12px 0 0;
        transition: all 0.3s;
        white-space: nowrap;
        position: relative;
      }

      .tab:hover,
      .tab.active {
        color: var(--primary);
        background: rgba(99, 102, 241, 0.05);
      }

      .tab.active::after {
        content: '';
        position: absolute;
        bottom: -0.6rem;
        left: 0;
        right: 0;
        height: 3px;
        background: var(--gradient-primary);
        border-radius: 3px 3px 0 0;
      }

      .grid {
        display: grid;
        gap: 1.5rem;
      }

      .grid-2 {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
      }

      .grid-3 {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
      }

      .grid-4 {
        grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
      }

      .card {
        background: white;
        border-radius: 16px;
        overflow: hidden;
        box-shadow: var(--shadow-sm);
        transition: all 0.3s;
        cursor: pointer;
      }

      .card:hover {
        transform: translateY(-6px);
        box-shadow: var(--shadow-lg);
      }

      .video-card .card-media {
        position: relative;
        width: 100%;
        padding-top: 56.25%;
        overflow: hidden;
      }

      .media-content {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 5rem;
      }

      .media-overlay {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.3);
        display: flex;
        align-items: center;
        justify-content: center;
        opacity: 0;
        transition: opacity 0.3s;
      }

      .card:hover .media-overlay {
        opacity: 1;
      }

      .play-icon {
        width: 60px;
        height: 60px;
        background: white;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem;
        color: var(--primary);
      }

      .video-duration {
        position: absolute;
        bottom: 0.5rem;
        right: 0.5rem;
        background: rgba(0, 0, 0, 0.8);
        color: white;
        padding: 0.25rem 0.5rem;
        border-radius: 6px;
        font-size: 0.85rem;
        font-weight: 600;
      }

      .card-content {
        padding: 1.25rem;
      }

      .card-header {
        display: flex;
        gap: 0.75rem;
        margin-bottom: 1rem;
      }

      .user-avatar {
        width: 44px;
        height: 44px;
        border-radius: 50%;
        background: var(--gradient-accent);
        display: flex;
        align-items: center;
        justify-content: center;
        color: white;
        font-size: 1.3rem;
        flex-shrink: 0;
      }

      .user-info {
        flex: 1;
        min-width: 0;
      }

      .user-name {
        font-weight: 700;
        color: var(--text-primary);
        margin-bottom: 0.25rem;
        font-size: 0.95rem;
      }

      .user-meta {
        font-size: 0.85rem;
        color: var(--text-secondary);
      }

      .card-title {
        font-size: 1.05rem;
        font-weight: 700;
        margin-bottom: 0.75rem;
        color: var(--text-primary);
        display: -webkit-box;
        -webkit-line-clamp: 2;
        -webkit-box-orient: vertical;
        overflow: hidden;
      }

      .card-stats {
        display: flex;
        gap: 1.25rem;
        font-size: 0.9rem;
        color: var(--text-secondary);
      }

      .stat-item {
        display: flex;
        align-items: center;
        gap: 0.4rem;
      }

      .topic-card {
        display: flex;
        gap: 1rem;
        padding: 1.5rem;
      }

      .topic-icon {
        width: 60px;
        height: 60px;
        border-radius: 12px;
        background: var(--gradient-primary);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 2rem;
        flex-shrink: 0;
      }

      .topic-info {
        flex: 1;
        min-width: 0;
      }

      .topic-title {
        font-size: 1.2rem;
        font-weight: 700;
        margin-bottom: 0.5rem;
        color: var(--text-primary);
      }

      .topic-desc {
        color: var(--text-secondary);
        margin-bottom: 0.75rem;
        font-size: 0.9rem;
      }

      .topic-stats {
        display: flex;
        gap: 1.5rem;
        font-size: 0.85rem;
        color: var(--text-secondary);
      }

      .profile-card {
        text-align: center;
        padding: 2rem 1.5rem;
      }

      .profile-avatar {
        width: 100px;
        height: 100px;
        border-radius: 50%;
        background: var(--gradient-secondary);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 3rem;
        color: white;
        margin: 0 auto 1rem;
        border: 4px solid white;
        box-shadow: var(--shadow-md);
      }

      .profile-name {
        font-size: 1.3rem;
        font-weight: 700;
        margin-bottom: 0.5rem;
      }

      .profile-bio {
        color: var(--text-secondary);
        margin-bottom: 1rem;
        font-size: 0.9rem;
      }

      .profile-tags {
        display: flex;
        gap: 0.5rem;
        justify-content: center;
        flex-wrap: wrap;
        margin-bottom: 1.5rem;
      }

      .tag {
        padding: 0.4rem 0.9rem;
        background: rgba(99, 102, 241, 0.1);
        color: var(--primary);
        border-radius: 20px;
        font-size: 0.85rem;
        font-weight: 600;
      }

      .profile-stats {
        display: flex;
        justify-content: space-around;
        padding: 1.25rem 0;
        border-top: 1px solid var(--border);
        border-bottom: 1px solid var(--border);
        margin-bottom: 1.25rem;
      }

      .profile-stat {
        text-align: center;
      }

      .profile-stat strong {
        display: block;
        font-size: 1.4rem;
        color: var(--text-primary);
        font-weight: 800;
        margin-bottom: 0.25rem;
      }

      .profile-stat span {
        font-size: 0.85rem;
        color: var(--text-secondary);
      }

      .match-badge {
        display: inline-block;
        padding: 0.5rem 1rem;
        background: rgba(236, 72, 153, 0.1);
        color: var(--secondary);
        border-radius: 20px;
        font-size: 0.9rem;
        font-weight: 600;
        margin-bottom: 1rem;
      }

      .sidebar {
        background: white;
        border-radius: 16px;
        padding: 1.5rem;
        box-shadow: var(--shadow-sm);
        margin-bottom: 2rem;
      }

      .sidebar-title {
        font-size: 1.2rem;
        font-weight: 800;
        margin-bottom: 1.5rem;
        color: var(--text-primary);
      }

      .sidebar-item {
        display: flex;
        align-items: center;
        gap: 1rem;
        padding: 1rem;
        border-radius: 12px;
        cursor: pointer;
        transition: background 0.3s;
        margin-bottom: 0.5rem;
      }

      .sidebar-item:hover {
        background: var(--light);
      }

      .sidebar-icon {
        width: 48px;
        height: 48px;
        border-radius: 50%;
        background: var(--gradient-accent);
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 1.5rem;
        color: white;
      }

      .sidebar-content {
        flex: 1;
        min-width: 0;
      }

      .sidebar-content h4 {
        font-size: 0.95rem;
        font-weight: 700;
        margin-bottom: 0.25rem;
        color: var(--text-primary);
      }

      .sidebar-content p {
        font-size: 0.85rem;
        color: var(--text-secondary);
      }

      .two-column {
        display: grid;
        grid-template-columns: 1fr 340px;
        gap: 2rem;
      }

      .forum-post {
        background: white;
        border-radius: 16px;
        padding: 1.5rem;
        margin-bottom: 1.5rem;
        box-shadow: var(--shadow-sm);
        transition: all 0.3s;
        cursor: pointer;
      }

      .forum-post:hover {
        box-shadow: var(--shadow-md);
        transform: translateX(4px);
      }

      .post-header {
        display: flex;
        justify-content: space-between;
        align-items: flex-start;
        margin-bottom: 1rem;
      }

      .post-user {
        display: flex;
        gap: 1rem;
      }

      .post-info h3 {
        font-size: 1.1rem;
        font-weight: 700;
        margin-bottom: 0.5rem;
      }

      .post-body {
        margin-bottom: 1rem;
        color: var(--text-primary);
        line-height: 1.7;
      }

      .post-tags {
        display: flex;
        gap: 0.5rem;
        flex-wrap: wrap;
        margin-bottom: 1rem;
      }

      .post-actions {
        display: flex;
        gap: 1.5rem;
        padding-top: 1rem;
        border-top: 1px solid var(--border);
      }

      .action-btn {
        display: flex;
        align-items: center;
        gap: 0.5rem;
        background: transparent;
        border: none;
        color: var(--text-secondary);
        cursor: pointer;
        font-weight: 600;
        font-size: 0.9rem;
        transition: color 0.3s;
      }

      .action-btn:hover {
        color: var(--primary);
      }

      .footer {
        background: var(--dark);
        color: white;
        margin-top: 4rem;
        padding: 3rem 0 1.5rem;
      }

      .footer-container {
        max-width: 1400px;
        margin: 0 auto;
        padding: 0 2rem;
      }

      .footer-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: 2rem;
        margin-bottom: 2rem;
      }

      .footer-section h4 {
        font-size: 1.1rem;
        font-weight: 700;
        margin-bottom: 1rem;
      }

      .footer-section ul {
        list-style: none;
      }

      .footer-section li {
        margin-bottom: 0.5rem;
      }

      .footer-section a {
        color: rgba(255, 255, 255, 0.7);
        text-decoration: none;
        transition: color 0.3s;
      }

      .footer-section a:hover {
        color: white;
      }

      .footer-bottom {
        text-align: center;
        padding-top: 2rem;
        border-top: 1px solid rgba(255, 255, 255, 0.1);
        color: rgba(255, 255, 255, 0.6);
      }

      @media (max-width: 1024px) {
        .nav-menu {
          display: none;
        }

        .two-column {
          grid-template-columns: 1fr;
        }

        .hero h1 {
          font-size: 2.5rem;
        }

        .hero p {
          font-size: 1.1rem;
        }
      }

      @media (max-width: 768px) {
        .container {
          padding: 1rem;
        }

        .header-container {
          padding: 1rem;
        }

        .search-input {
          display: none;
        }

        .hero {
          padding: 2rem 1rem;
        }

        .hero h1 {
          font-size: 2rem;
        }

        .hero p {
          font-size: 1rem;
        }

        .grid-2,
        .grid-3,
        .grid-4 {
          grid-template-columns: 1fr;
        }

        .topic-card {
          flex-direction: column;
          text-align: center;
        }

        .topic-icon {
          margin: 0 auto;
        }
      }