/* CSS Reset & Variables - Vibrant Gradient Style (活力亮彩渐变风) */
    :root {
      --primary-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
      --secondary-gradient: linear-gradient(135deg, #06b6d4 0%, #3b82f6 100%);
      --accent-gradient: linear-gradient(135deg, #f59e0b 0%, #ef4444 100%);
      --soft-bg: #f8fafc;
      --card-bg: #ffffff;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-light: #64748b;
      --border-color: #e2e8f0;
      --primary-color: #6366f1;
      --primary-hover: #4f46e5;
      --shadow-sm: 0 2px 8px rgba(99, 102, 241, 0.06);
      --shadow-md: 0 8px 24px rgba(149, 157, 165, 0.12);
      --shadow-lg: 0 16px 32px rgba(99, 102, 241, 0.15);
      --radius-sm: 8px;
      --radius-md: 14px;
      --radius-lg: 20px;
    }

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

    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
      background-color: var(--soft-bg);
      color: var(--text-main);
      line-height: 1.6;
    }

    body {
      overflow-x: hidden;
    }

    /* Container Standard */
    .container {
      width: 100%;
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* Typography & Headers */
    h1, h2, h3, h4 {
      color: var(--text-main);
      font-weight: 700;
      line-height: 1.3;
    }

    .section-title-wrap {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-tag {
      display: inline-block;
      padding: 4px 16px;
      background: linear-gradient(90deg, rgba(99, 102, 241, 0.1), rgba(236, 72, 153, 0.1));
      color: var(--primary-color);
      font-weight: 600;
      font-size: 14px;
      border-radius: 20px;
      margin-bottom: 12px;
      border: 1px solid rgba(99, 102, 241, 0.2);
    }

    .section-title {
      font-size: 32px;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 12px;
    }

    .section-subtitle {
      font-size: 16px;
      color: var(--text-muted);
      max-width: 700px;
      margin: 0 auto;
    }

    section {
      padding: 80px 0;
      position: relative;
    }

    /* Buttons */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      font-size: 15px;
      font-weight: 600;
      border-radius: 30px;
      text-decoration: none;
      transition: all 0.3s ease;
      cursor: pointer;
      border: none;
      outline: none;
    }

    .btn-primary {
      background: var(--primary-gradient);
      color: #ffffff !important;
      box-shadow: 0 4px 15px rgba(99, 102, 241, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 25px rgba(99, 102, 241, 0.5);
    }

    .btn-secondary {
      background: #ffffff;
      color: var(--text-main) !important;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .btn-secondary:hover {
      background: var(--soft-bg);
      border-color: var(--primary-color);
      color: var(--primary-color) !important;
    }

    /* Header Nav */
    header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(226, 232, 240, 0.8);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }

    .ai-page-logo {
      height: 40px;
      width: auto;
      object-fit: contain;
    }

    .brand-name {
      font-size: 20px;
      font-weight: 800;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    /* Strict rule: .nav-links gap set to 0 */
    .nav-links {
      display: flex;
      align-items: center;
      list-style: none;
      gap: 0; 
    }

    .nav-links li a {
      padding: 8px 14px;
      color: var(--text-main);
      font-size: 14px;
      font-weight: 500;
      text-decoration: none;
      transition: color 0.2s ease;
      white-space: nowrap;
    }

    .nav-links li a:hover,
    .nav-links li a.ai-page-home-link {
      color: var(--primary-color);
    }

    .nav-cta {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--text-main);
      cursor: pointer;
    }

    /* Hero Section (Strictly NO Images allowed here) */
    .hero-section {
      padding: 100px 0 80px 0;
      background: radial-gradient(circle at 50% 20%, rgba(99, 102, 241, 0.12) 0%, rgba(236, 72, 153, 0.05) 50%, rgba(248, 250, 252, 0) 100%);
      text-align: center;
      position: relative;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 20px;
      background: #ffffff;
      border: 1px solid rgba(99, 102, 241, 0.3);
      border-radius: 30px;
      font-size: 14px;
      color: var(--primary-color);
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(99, 102, 241, 0.1);
      margin-bottom: 24px;
    }

    .hero-title {
      font-size: 44px;
      font-weight: 900;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
      line-height: 1.25;
      background: linear-gradient(135deg, #0f172a 0%, #334155 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-title span {
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 820px;
      margin: 0 auto 36px auto;
      line-height: 1.7;
    }

    .hero-btns {
      display: flex;
      justify-content: center;
      gap: 16px;
      margin-bottom: 60px;
      flex-wrap: wrap;
    }

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      background: #ffffff;
      padding: 30px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-md);
      border: 1px solid var(--border-color);
    }

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

    .stat-num {
      font-size: 32px;
      font-weight: 800;
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 4px;
    }

    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
    }

    /* Cards & Grid General */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 30px;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 28px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
    }

    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-md);
      border-color: rgba(99, 102, 241, 0.4);
    }

    /* Platform Intro Block */
    .intro-box {
      background: linear-gradient(135deg, #ffffff 0%, #f1f5f9 100%);
      border-radius: var(--radius-lg);
      padding: 40px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .intro-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
      margin-top: 24px;
    }

    .intro-tag-item {
      padding: 6px 14px;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: 20px;
      font-size: 13px;
      color: var(--text-main);
      font-weight: 500;
    }

    /* Scenario Cards (一站式制作) */
    .scenario-card {
      background: #ffffff;
      border-radius: var(--radius-md);
      padding: 24px;
      border: 1px solid var(--border-color);
      position: relative;
      overflow: hidden;
      transition: all 0.3s ease;
    }

    .scenario-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 4px;
      height: 100%;
      background: var(--primary-gradient);
    }

    .scenario-card h3 {
      font-size: 18px;
      margin-bottom: 10px;
      color: var(--text-main);
    }

    .scenario-card p {
      font-size: 14px;
      color: var(--text-muted);
    }

    /* Process Steps */
    .step-list {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      position: relative;
    }

    .step-item {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      position: relative;
      text-align: center;
    }

    .step-num {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      font-weight: 700;
      font-size: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 16px auto;
    }

    /* Comparison Table (对比评测) */
    .eval-card {
      background: #ffffff;
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
    }

    .score-header {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding-bottom: 24px;
      border-bottom: 1px solid var(--border-color);
      margin-bottom: 24px;
      flex-wrap: wrap;
      gap: 16px;
    }

    .score-badge {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .stars {
      color: #f59e0b;
      font-size: 24px;
      letter-spacing: 2px;
    }

    .score-num {
      font-size: 36px;
      font-weight: 900;
      color: var(--primary-color);
    }

    .eval-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
    }

    .eval-table th, .eval-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-color);
      font-size: 15px;
    }

    .eval-table th {
      background: var(--soft-bg);
      color: var(--text-main);
      font-weight: 700;
    }

    .highlight-col {
      background: rgba(99, 102, 241, 0.04);
      font-weight: 600;
      color: var(--primary-color);
    }

    /* Reviews / Testimonials */
    .review-card {
      background: #ffffff;
      padding: 24px;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .review-user {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
    }

    .avatar-placeholder {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
    }

    .user-info h4 {
      font-size: 16px;
      color: var(--text-main);
    }

    .user-info p {
      font-size: 13px;
      color: var(--text-light);
    }

    .review-text {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* FAQ Accordion */
    .faq-list {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .faq-item {
      background: #ffffff;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      overflow: hidden;
      transition: all 0.2s ease;
    }

    .faq-title {
      padding: 20px 24px;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      user-select: none;
    }

    .faq-icon {
      font-size: 20px;
      transition: transform 0.3s ease;
      color: var(--primary-color);
    }

    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
      background: var(--soft-bg);
      padding: 0 24px;
      color: var(--text-muted);
      font-size: 14px;
      line-height: 1.7;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    .faq-item.active .faq-content {
      max-height: 500px;
      padding: 16px 24px 20px 24px;
      border-top: 1px solid var(--border-color);
    }

    /* Article List / Media Gallery */
    .media-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
      margin-top: 24px;
    }

    .media-card img {
      width: 100%;
      height: 240px;
      object-fit: cover;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
    }

    .article-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .article-item a {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 16px 20px;
      background: #ffffff;
      border-radius: var(--radius-sm);
      border: 1px solid var(--border-color);
      text-decoration: none;
      color: var(--text-main);
      font-weight: 500;
      transition: all 0.2s ease;
    }

    .article-item a:hover {
      border-color: var(--primary-color);
      color: var(--primary-color);
      transform: translateX(4px);
    }

    /* Form Styling */
    .form-wrap {
      background: #ffffff;
      padding: 40px;
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-md);
    }

    .form-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
      margin-bottom: 20px;
    }

    .form-group {
      display: flex;
      flex-direction: column;
      gap: 8px;
    }

    .form-group.full {
      grid-column: span 2;
    }

    .form-group label {
      font-size: 14px;
      font-weight: 600;
      color: var(--text-main);
    }

    .form-input, .form-select, .form-textarea {
      padding: 12px 16px;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 14px;
      color: var(--text-main);
      outline: none;
      transition: border-color 0.2s ease;
      background: var(--soft-bg);
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      border-color: var(--primary-color);
      background: #ffffff;
    }

    .form-textarea {
      resize: vertical;
      min-height: 120px;
    }

    /* Footer & Friend links */
    footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 60px 0 30px 0;
      border-top: 1px solid #1e293b;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 16px;
      margin-bottom: 20px;
    }

    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .footer-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 14px;
      transition: color 0.2s ease;
    }

    .footer-links a:hover {
      color: #ffffff;
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 16px;
    }

    .friend-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 13px;
      padding: 4px 10px;
      background: #1e293b;
      border-radius: 4px;
      transition: all 0.2s ease;
    }

    .friend-links a:hover {
      color: #ffffff;
      background: var(--primary-color);
    }

    .qr-box {
      text-align: center;
    }

    .qr-box img {
      width: 120px;
      height: 120px;
      border-radius: 8px;
      margin-bottom: 8px;
    }

    .copyright-bar {
      border-top: 1px solid #1e293b;
      padding-top: 24px;
      text-align: center;
      font-size: 13px;
      color: #64748b;
    }

    /* Floating Customer Service Button */
    .floating-kefu {
      position: fixed;
      right: 24px;
      bottom: 24px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .float-btn {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background: var(--primary-gradient);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: var(--shadow-lg);
      text-decoration: none;
      font-size: 20px;
      cursor: pointer;
      transition: transform 0.3s ease;
    }

    .float-btn:hover {
      transform: scale(1.1);
    }

    /* Responsive */
    @media (max-width: 1024px) {
      .hero-stats {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-4, .step-list {
        grid-template-columns: repeat(2, 1fr);
      }
      .grid-3 {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .menu-toggle {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: #ffffff;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow-md);
        border-bottom: 1px solid var(--border-color);
      }
      .nav-links.active {
        display: flex;
      }
      .nav-cta {
        display: none;
      }
      .hero-title {
        font-size: 30px;
      }
      .grid-3, .grid-4, .grid-2, .hero-stats, .step-list, .media-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .form-grid {
        grid-template-columns: 1fr;
      }
      .form-group.full {
        grid-column: span 1;
      }
      .eval-table {
        display: block;
        overflow-x: auto;
      }
    }