/* -------------------------------------------------------------
       CSS RESET & VARIABLES - 极致鲜亮风 (Vibrant Light Style)
       ------------------------------------------------------------- */
    :root {
      --primary: #2563eb;
      --primary-hover: #1d4ed8;
      --primary-light: #eff6ff;
      --secondary: #06b6d4;
      --accent: #7c3aed;
      --accent-vibrant: #ff3b30;
      --bg-page: #f8fafc;
      --bg-surface: #ffffff;
      --bg-alt: #f1f5f9;
      --text-main: #0f172a;
      --text-sub: #475569;
      --text-muted: #64748b;
      --border-color: #e2e8f0;
      --border-focus: #93c5fd;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
      --shadow-md: 0 4px 12px rgba(37,99,235,0.08);
      --shadow-lg: 0 12px 28px rgba(37,99,235,0.12);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --container-max: 1200px;
    }

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

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

    body {
      overflow-x: hidden;
    }

    /* Container Standard */
    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 1.25rem;
    }

    /* -------------------------------------------------------------
       NAVIGATION
       ------------------------------------------------------------- */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

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

    .brand-logo {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      text-decoration: none;
    }

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

    .brand-title {
      font-size: 1.25rem;
      font-weight: 800;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

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

    .nav-links li a {
      display: block;
      padding: 0.5rem 0.75rem;
      font-size: 0.925rem;
      font-weight: 600;
      color: var(--text-sub);
      text-decoration: none;
      transition: color 0.2s, background-color 0.2s;
      border-radius: var(--radius-sm);
    }

    .nav-links li a:hover {
      color: var(--primary);
      background-color: var(--primary-light);
    }

    .nav-cta {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.65rem 1.4rem;
      font-size: 0.95rem;
      font-weight: 700;
      border-radius: var(--radius-md);
      text-decoration: none;
      transition: all 0.25s ease;
      cursor: pointer;
      border: none;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary), #1d4ed8);
      color: #ffffff !important;
      box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(37, 99, 235, 0.45);
    }

    .btn-vibrant {
      background: linear-gradient(135deg, #06b6d4, #3b82f6);
      color: #ffffff !important;
      box-shadow: 0 4px 14px rgba(6, 182, 212, 0.35);
    }

    .btn-vibrant:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(6, 182, 212, 0.45);
    }

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

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

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      color: var(--text-main);
      cursor: pointer;
    }

    /* -------------------------------------------------------------
       HERO SECTION (Strictly NO Images inside Hero)
       ------------------------------------------------------------- */
    .hero-section {
      padding: 4.5rem 0 3.5rem;
      background: linear-gradient(180deg, #ffffff 0%, #eff6ff 50%, #f8fafc 100%);
      position: relative;
      overflow: hidden;
      border-bottom: 1px solid var(--border-color);
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      padding: 0.35rem 1rem;
      background: rgba(37, 99, 235, 0.1);
      border: 1px solid rgba(37, 99, 235, 0.2);
      border-radius: 50px;
      color: var(--primary);
      font-size: 0.875rem;
      font-weight: 700;
      margin-bottom: 1.25rem;
    }

    .hero-title {
      font-size: 2.5rem;
      font-weight: 900;
      color: var(--text-main);
      line-height: 1.25;
      margin-bottom: 1.25rem;
      letter-spacing: -0.5px;
    }

    .hero-title span {
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-desc {
      font-size: 1.15rem;
      color: var(--text-sub);
      max-width: 800px;
      margin-bottom: 2rem;
      line-height: 1.7;
    }

    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
      margin-bottom: 3rem;
    }

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 1.25rem;
    }

    .stat-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 1.25rem;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: transform 0.3s ease;
    }

    .stat-card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-md);
    }

    .stat-num {
      font-size: 2rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 0.25rem;
    }

    .stat-label {
      font-size: 0.875rem;
      color: var(--text-sub);
      font-weight: 600;
    }

    /* -------------------------------------------------------------
       SECTION GENERAL STYLES
       ------------------------------------------------------------- */
    .section-padding {
      padding: 4.5rem 0;
    }

    .section-title-wrap {
      text-align: center;
      max-width: 750px;
      margin: 0 auto 3rem;
    }

    .section-subtitle {
      text-transform: uppercase;
      font-size: 0.85rem;
      font-weight: 800;
      letter-spacing: 1.5px;
      color: var(--primary);
      margin-bottom: 0.5rem;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 800;
      color: var(--text-main);
      margin-bottom: 1rem;
    }

    .section-desc {
      font-size: 1rem;
      color: var(--text-sub);
    }

    /* -------------------------------------------------------------
       GRID & CARD COMPONENTS
       ------------------------------------------------------------- */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 1.5rem;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 1.25rem;
    }

    .card {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 1.75rem;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      box-shadow: var(--shadow-lg);
      transform: translateY(-4px);
      border-color: var(--border-focus);
    }

    .card-icon {
      width: 48px;
      height: 48px;
      border-radius: var(--radius-sm);
      background: var(--primary-light);
      color: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.5rem;
      font-weight: bold;
      margin-bottom: 1.25rem;
    }

    .card-title {
      font-size: 1.2rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 0.75rem;
    }

    .card-text {
      font-size: 0.95rem;
      color: var(--text-sub);
      line-height: 1.6;
      flex-grow: 1;
    }

    /* Tag Cloud */
    .tags-wrapper {
      display: flex;
      flex-wrap: wrap;
      gap: 0.6rem;
      margin-top: 1rem;
    }

    .tag-chip {
      padding: 0.3rem 0.75rem;
      background: var(--bg-alt);
      border: 1px solid var(--border-color);
      border-radius: 50px;
      font-size: 0.825rem;
      color: var(--text-sub);
      font-weight: 600;
    }

    .tag-chip.active {
      background: var(--primary-light);
      color: var(--primary);
      border-color: rgba(37, 99, 235, 0.3);
    }

    /* -------------------------------------------------------------
       COMPARISON TABLE SECTION (9.9/10, 5 Stars)
       ------------------------------------------------------------- */
    .rating-banner {
      background: linear-gradient(135deg, #1e3a8a, #2563eb);
      color: #ffffff;
      border-radius: var(--radius-lg);
      padding: 2.5rem;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      gap: 2rem;
      margin-bottom: 2.5rem;
      box-shadow: var(--shadow-lg);
    }

    .rating-score-box {
      display: flex;
      align-items: center;
      gap: 1.5rem;
    }

    .rating-score {
      font-size: 3.5rem;
      font-weight: 900;
      line-height: 1;
      color: #facc15;
    }

    .stars {
      color: #facc15;
      font-size: 1.5rem;
      letter-spacing: 2px;
    }

    .compare-table-wrapper {
      width: 100%;
      overflow-x: auto;
      background: var(--bg-surface);
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      box-shadow: var(--shadow-sm);
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      min-width: 650px;
    }

    .compare-table th, .compare-table td {
      padding: 1.1rem 1.25rem;
      border-bottom: 1px solid var(--border-color);
      font-size: 0.95rem;
    }

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

    .compare-table tr:hover {
      background-color: var(--primary-light);
    }

    .highlight-cell {
      background: rgba(37, 99, 235, 0.05);
      font-weight: 700;
      color: var(--primary);
    }

    /* -------------------------------------------------------------
       PROCESS STEPS (TIMELINE)
       ------------------------------------------------------------- */
    .steps-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 1.5rem;
      position: relative;
    }

    .step-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 1.5rem;
      position: relative;
    }

    .step-num {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      width: 36px;
      height: 36px;
      background: var(--primary);
      color: #ffffff;
      border-radius: 50%;
      font-weight: 800;
      font-size: 1rem;
      margin-bottom: 1rem;
    }

    /* -------------------------------------------------------------
       IMAGE MEDIA GALLERY / CASES
       ------------------------------------------------------------- */
    .media-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .media-img-wrapper {
      width: 100%;
      height: 200px;
      overflow: hidden;
      background: var(--bg-alt);
    }

    .ai-page-image {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.3s ease;
    }

    .media-card:hover .ai-page-image {
      transform: scale(1.05);
    }

    .media-content {
      padding: 1.25rem;
    }

    /* -------------------------------------------------------------
       REVIEWS / TESTIMONIALS (6 User Reviews)
       ------------------------------------------------------------- */
    .review-card {
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 1.5rem;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .review-header {
      display: flex;
      align-items: center;
      gap: 1rem;
      margin-bottom: 1rem;
    }

    .avatar-placeholder {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.1rem;
    }

    .reviewer-name {
      font-weight: 700;
      color: var(--text-main);
      font-size: 1rem;
    }

    .reviewer-role {
      font-size: 0.85rem;
      color: var(--text-sub);
    }

    .review-quote {
      font-size: 0.95rem;
      color: var(--text-sub);
      font-style: italic;
      line-height: 1.6;
    }

    /* -------------------------------------------------------------
       FAQ ACCORDION (10+ Items)
       ------------------------------------------------------------- */
    .faq-list {
      max-width: 900px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 1rem;
    }

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

    .faq-question {
      width: 100%;
      padding: 1.25rem 1.5rem;
      text-align: left;
      background: none;
      border: none;
      font-size: 1.05rem;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .faq-question:hover {
      color: var(--primary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: var(--bg-page);
    }

    .faq-answer-inner {
      padding: 0 1.5rem 1.25rem;
      font-size: 0.95rem;
      color: var(--text-sub);
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
    }

    .faq-icon {
      font-size: 1.25rem;
      transition: transform 0.3s ease;
    }

    .faq-item.active .faq-icon {
      transform: rotate(180deg);
    }

    /* -------------------------------------------------------------
       FORM & CONTACT SECTION (?s=index/submitForm)
       ------------------------------------------------------------- */
    .contact-container {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 2.5rem;
      background: var(--bg-surface);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 2.5rem;
      box-shadow: var(--shadow-md);
    }

    .contact-info {
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

    .qr-card {
      display: flex;
      align-items: center;
      gap: 1.25rem;
      background: var(--bg-alt);
      padding: 1rem;
      border-radius: var(--radius-md);
      border: 1px solid var(--border-color);
      margin-top: 1.5rem;
    }

    .qr-card img {
      width: 90px;
      height: 90px;
      object-fit: cover;
      border-radius: var(--radius-sm);
    }

    .form-group {
      margin-bottom: 1.25rem;
    }

    .form-label {
      display: block;
      font-size: 0.9rem;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 0.4rem;
    }

    .form-input, .form-select, .form-textarea {
      width: 100%;
      padding: 0.75rem 1rem;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-sm);
      font-size: 0.95rem;
      color: var(--text-main);
      background: var(--bg-surface);
      transition: border-color 0.2s, box-shadow 0.2s;
    }

    .form-input:focus, .form-select:focus, .form-textarea:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
    }

    /* -------------------------------------------------------------
       FOOTER & LINKS
       ------------------------------------------------------------- */
    .site-footer {
      background: #0f172a;
      color: #94a3b8;
      padding: 4rem 0 2rem;
      border-top: 1px solid #1e293b;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr repeat(3, 1fr);
      gap: 2rem;
      margin-bottom: 3rem;
    }

    .footer-brand h3 {
      color: #ffffff;
      font-size: 1.3rem;
      margin-bottom: 1rem;
    }

    .footer-brand p {
      font-size: 0.9rem;
      line-height: 1.6;
      margin-bottom: 1rem;
    }

    .footer-col h4 {
      color: #ffffff;
      font-size: 1rem;
      margin-bottom: 1rem;
    }

    .footer-links {
      list-style: none;
    }

    .footer-links li {
      margin-bottom: 0.6rem;
    }

    .footer-links a {
      color: #94a3b8;
      text-decoration: none;
      font-size: 0.9rem;
      transition: color 0.2s;
    }

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

    .friendship-links {
      border-top: 1px solid #1e293b;
      padding-top: 1.5rem;
      margin-bottom: 1.5rem;
    }

    .friendship-links h5 {
      color: #cbd5e1;
      font-size: 0.875rem;
      margin-bottom: 0.75rem;
    }

    .friendship-links-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 0.75rem 1.25rem;
    }

    .friendship-links-grid a {
      color: #94a3b8;
      font-size: 0.85rem;
      text-decoration: none;
    }

    .friendship-links-grid a:hover {
      color: #38bdf8;
    }

    .copyright {
      text-align: center;
      font-size: 0.85rem;
      color: #64748b;
      border-top: 1px solid #1e293b;
      padding-top: 1.5rem;
    }

    .ai-page-home-link {
      color: #38bdf8;
      text-decoration: none;
      font-weight: 600;
    }

    /* -------------------------------------------------------------
       FLOATING CUSTOMER SERVICE WIDGET
       ------------------------------------------------------------- */
    .float-widget {
      position: fixed;
      right: 1.5rem;
      bottom: 2rem;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 0.75rem;
    }

    .float-btn {
      width: 52px;
      height: 52px;
      border-radius: 50%;
      background: var(--primary);
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.25rem;
      box-shadow: var(--shadow-lg);
      cursor: pointer;
      border: none;
      transition: transform 0.2s, background-color 0.2s;
      text-decoration: none;
    }

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

    .float-qr-popup {
      position: absolute;
      right: 64px;
      bottom: 0;
      background: #ffffff;
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      padding: 1rem;
      box-shadow: var(--shadow-lg);
      display: none;
      width: 180px;
      text-align: center;
    }

    .float-qr-popup img {
      width: 140px;
      height: 140px;
      object-fit: cover;
      border-radius: 6px;
    }

    .float-qr-popup p {
      font-size: 0.8rem;
      color: var(--text-main);
      font-weight: 700;
      margin-top: 0.5rem;
    }

    /* -------------------------------------------------------------
       RESPONSIVE DESIGN
       ------------------------------------------------------------- */
    @media (max-width: 992px) {
      .nav-links {
        display: none;
      }

      .mobile-menu-btn {
        display: block;
      }

      .contact-container {
        grid-template-columns: 1fr;
      }

      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }

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

    @media (max-width: 640px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }

      .rating-banner {
        flex-direction: column;
        text-align: center;
      }

      .rating-score-box {
        flex-direction: column;
        gap: 0.5rem;
      }

      .hero-actions {
        flex-direction: column;
        width: 100%;
      }

      .hero-actions .btn {
        width: 100%;
      }
    }