:root {
      --c-bg: #f8fafc;
      --c-surface: #ffffff;
      --c-text-main: #0f172a;
      --c-text-muted: #475569;
      --c-primary: #1d4ed8;
      --c-primary-light: #eff6ff;
      --c-accent-coral: #ea580c;
      --c-accent-amber: #f59e0b;
      --c-accent-cyan: #0284c7;
      --c-accent-lime: #16a34a;
      --c-border: #e2e8f0;
      --c-border-strong: #0f172a;
      --shadow-pop: 4px 4px 0px #0f172a;
      --shadow-pop-sm: 2px 2px 0px #0f172a;
      --shadow-pop-lg: 6px 6px 0px #0f172a;
      --radius-box: 12px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--c-bg);
      color: var(--c-text-main);
      line-height: 1.6;
      background-image: radial-gradient(#cbd5e1 1px, transparent 1px);
      background-size: 24px 24px;
    }

    .container {
      width: 100%;
      max-width: 1240px;
      margin: 0 auto;
      padding: 0 24px;
    }

    header.site-header {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: #ffffff;
      border-bottom: 3px solid var(--c-border-strong);
      box-shadow: 0 2px 0 rgba(0,0,0,0.05);
    }

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

    .brand-wrap {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .brand-wrap .ai-page-logo {
      height: 42px;
      width: auto;
      display: block;
    }

    .brand-title {
      font-size: 1.25rem;
      font-weight: 800;
      color: var(--c-text-main);
      letter-spacing: -0.5px;
    }

    .brand-title span {
      color: var(--c-accent-coral);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 0;
      list-style: none;
    }

    .nav-links a {
      color: var(--c-text-main);
      text-decoration: none;
      font-weight: 600;
      font-size: 0.92rem;
      padding: 8px 12px;
      border-radius: 6px;
      transition: all 0.2s ease;
      display: inline-block;
    }

    .nav-links a:hover {
      background-color: #fef08a;
      color: #000;
      transform: translateY(-2px);
    }

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

    .btn-action-hero {
      background-color: #facc15;
      color: var(--c-text-main);
      padding: 10px 20px;
      font-weight: 700;
      font-size: 0.95rem;
      text-decoration: none;
      border: 2px solid var(--c-border-strong);
      border-radius: 8px;
      box-shadow: var(--shadow-pop-sm);
      transition: all 0.15s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }

    .btn-action-hero:hover {
      transform: translate(-1px, -1px);
      box-shadow: var(--shadow-pop);
      background-color: #fde047;
    }

    .btn-action-hero:active {
      transform: translate(2px, 2px);
      box-shadow: 0 0 0 transparent;
    }

    .nav-toggle {
      display: none;
      background: none;
      border: 2px solid var(--c-border-strong);
      border-radius: 6px;
      padding: 6px 10px;
      font-weight: bold;
      cursor: pointer;
    }

    /* Hero Section - Strict No Image Rule Followed */
    .hero-section {
      padding: 64px 0 54px;
      background: linear-gradient(135deg, #fffbeb 0%, #ffffff 50%, #eff6ff 100%);
      border-bottom: 3px solid var(--c-border-strong);
      position: relative;
      overflow: hidden;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 40px;
      align-items: center;
    }

    .hero-tagline {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 6px 14px;
      background: #fed7aa;
      border: 2px solid var(--c-border-strong);
      border-radius: 999px;
      font-weight: 800;
      font-size: 0.85rem;
      color: #9a3412;
      margin-bottom: 20px;
      box-shadow: var(--shadow-pop-sm);
    }

    .hero-content h1 {
      font-size: 2.25rem;
      line-height: 1.25;
      font-weight: 900;
      color: var(--c-text-main);
      margin-bottom: 18px;
      letter-spacing: -0.5px;
    }

    .hero-content h1 mark {
      background: #fde047;
      color: #0f172a;
      padding: 0 6px;
      border-radius: 4px;
    }

    .hero-desc {
      font-size: 1.08rem;
      color: var(--c-text-muted);
      margin-bottom: 28px;
      line-height: 1.65;
    }

    .hero-cta-group {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
      margin-bottom: 32px;
    }

    .btn-main-pop {
      background: var(--c-accent-coral);
      color: #ffffff;
      padding: 14px 28px;
      font-size: 1.05rem;
      font-weight: 800;
      text-decoration: none;
      border: 2px solid var(--c-border-strong);
      border-radius: 10px;
      box-shadow: var(--shadow-pop);
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: all 0.15s ease;
    }

    .btn-main-pop:hover {
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-pop-lg);
      background: #c2410c;
    }

    .btn-sub-pop {
      background: #ffffff;
      color: var(--c-text-main);
      padding: 14px 24px;
      font-size: 1.05rem;
      font-weight: 700;
      text-decoration: none;
      border: 2px solid var(--c-border-strong);
      border-radius: 10px;
      box-shadow: var(--shadow-pop);
      transition: all 0.15s ease;
    }

    .btn-sub-pop:hover {
      background: #f1f5f9;
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-pop-lg);
    }

    .hero-metrics {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
      padding-top: 18px;
      border-top: 2px dashed var(--c-border);
    }

    .metric-item strong {
      display: block;
      font-size: 1.45rem;
      font-weight: 900;
      color: var(--c-primary);
    }

    .metric-item span {
      font-size: 0.85rem;
      color: var(--c-text-muted);
      font-weight: 600;
    }

    .hero-feature-board {
      background: #ffffff;
      border: 3px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      box-shadow: var(--shadow-pop-lg);
      padding: 24px;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .feature-board-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-bottom: 2px solid var(--c-border);
      padding-bottom: 12px;
    }

    .feature-badge {
      background: #dbeafe;
      color: var(--c-primary);
      font-size: 0.8rem;
      font-weight: 800;
      padding: 4px 10px;
      border-radius: 6px;
      border: 1px solid #bfdbfe;
    }

    .pulse-indicator {
      display: inline-block;
      width: 10px;
      height: 10px;
      background-color: var(--c-accent-lime);
      border-radius: 50%;
      box-shadow: 0 0 0 3px rgba(22, 163, 74, 0.2);
    }

    .model-tags-box {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
    }

    .model-pill {
      background: #f8fafc;
      border: 1.5px solid var(--c-border-strong);
      padding: 5px 10px;
      border-radius: 6px;
      font-size: 0.8rem;
      font-weight: 700;
      color: var(--c-text-main);
      box-shadow: 1px 1px 0px var(--c-border-strong);
    }

    .model-pill.highlight {
      background: #fef08a;
    }

    .model-pill.accent {
      background: #ccfbf1;
    }

    .board-status-row {
      background: #f1f5f9;
      border-radius: 8px;
      padding: 12px;
      display: flex;
      justify-content: space-between;
      font-size: 0.88rem;
      border: 1px solid var(--c-border);
    }

    .board-status-row span:last-child {
      font-weight: 800;
      color: var(--c-accent-coral);
    }

    /* Universal Section Styling */
    section {
      padding: 72px 0;
      border-bottom: 2px solid var(--c-border);
    }

    .section-head {
      text-align: center;
      max-width: 760px;
      margin: 0 auto 48px;
    }

    .section-eyebrow {
      display: inline-block;
      font-size: 0.82rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: 1px;
      background: #e0e7ff;
      color: #3730a3;
      padding: 4px 12px;
      border-radius: 999px;
      margin-bottom: 12px;
      border: 1px solid #c7d2fe;
    }

    .section-title {
      font-size: 1.95rem;
      font-weight: 900;
      color: var(--c-text-main);
      margin-bottom: 12px;
    }

    .section-subtitle {
      font-size: 1rem;
      color: var(--c-text-muted);
      line-height: 1.6;
    }

    /* Cards & Grids */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 24px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 20px;
    }

    .card-pop {
      background: var(--c-surface);
      border: 2px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      padding: 24px;
      box-shadow: var(--shadow-pop);
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      display: flex;
      flex-direction: column;
    }

    .card-pop:hover {
      transform: translate(-3px, -3px);
      box-shadow: var(--shadow-pop-lg);
    }

    .card-icon-badge {
      width: 48px;
      height: 48px;
      border-radius: 10px;
      border: 2px solid var(--c-border-strong);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 900;
      font-size: 1.25rem;
      margin-bottom: 16px;
      box-shadow: 2px 2px 0px var(--c-border-strong);
    }

    .bg-amber { background: #fef08a; }
    .bg-cyan { background: #bae6fd; }
    .bg-pink { background: #fbcfe8; }
    .bg-lime { background: #bbf7d0; }
    .bg-purple { background: #ddd6fe; }
    .bg-orange { background: #fed7aa; }

    .card-title {
      font-size: 1.2rem;
      font-weight: 800;
      margin-bottom: 10px;
      color: var(--c-text-main);
    }

    .card-desc {
      font-size: 0.92rem;
      color: var(--c-text-muted);
      line-height: 1.6;
      margin-bottom: 16px;
      flex-grow: 1;
    }

    .card-tags {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      margin-top: auto;
    }

    .tag-chip {
      font-size: 0.75rem;
      font-weight: 700;
      background: #f1f5f9;
      color: #334155;
      padding: 3px 8px;
      border-radius: 4px;
      border: 1px solid var(--c-border);
    }

    /* Comparison Table */
    .table-container {
      background: #ffffff;
      border: 3px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      box-shadow: var(--shadow-pop-lg);
      overflow-x: auto;
      margin-top: 24px;
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 0.95rem;
    }

    .compare-table th, .compare-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--c-border);
    }

    .compare-table th {
      background: #f8fafc;
      font-weight: 800;
      color: var(--c-text-main);
      border-bottom: 2px solid var(--c-border-strong);
    }

    .compare-table tr:hover td {
      background: #f8fafc;
    }

    .col-highlight {
      background: #fefce8;
      font-weight: 700;
      border-left: 2px solid var(--c-border-strong);
      border-right: 2px solid var(--c-border-strong);
    }

    .score-badge {
      display: inline-block;
      background: #ea580c;
      color: #ffffff;
      padding: 4px 10px;
      border-radius: 6px;
      font-weight: 800;
      border: 1px solid var(--c-border-strong);
    }

    /* Process Flow */
    .step-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
      gap: 20px;
      position: relative;
    }

    .step-card {
      background: #ffffff;
      border: 2px solid var(--c-border-strong);
      border-radius: 12px;
      padding: 20px;
      box-shadow: var(--shadow-pop-sm);
      position: relative;
    }

    .step-num {
      width: 32px;
      height: 32px;
      background: #0f172a;
      color: #ffffff;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      font-weight: 800;
      font-size: 0.9rem;
      margin-bottom: 12px;
    }

    /* Image Gallery Section */
    .gallery-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 20px;
    }

    .gallery-card {
      background: #ffffff;
      border: 2px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      overflow: hidden;
      box-shadow: var(--shadow-pop);
      display: flex;
      flex-direction: column;
    }

    .gallery-card .img-wrap {
      width: 100%;
      background: #e2e8f0;
      aspect-ratio: 16 / 9;
      overflow: hidden;
      border-bottom: 2px solid var(--c-border-strong);
    }

    .gallery-card .img-wrap.square {
      aspect-ratio: 1 / 1;
    }

    .gallery-card img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.3s ease;
    }

    .gallery-card:hover img {
      transform: scale(1.03);
    }

    .gallery-info {
      padding: 16px;
    }

    .gallery-title {
      font-weight: 800;
      font-size: 1rem;
      margin-bottom: 6px;
    }

    .gallery-desc {
      font-size: 0.85rem;
      color: var(--c-text-muted);
    }

    /* Form Section */
    .form-box {
      background: #ffffff;
      border: 3px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      box-shadow: var(--shadow-pop-lg);
      padding: 36px;
      max-width: 800px;
      margin: 0 auto;
    }

    .form-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 16px;
      margin-bottom: 16px;
    }

    .form-group {
      display: flex;
      flex-direction: column;
      gap: 6px;
      margin-bottom: 16px;
    }

    .form-group label {
      font-weight: 700;
      font-size: 0.9rem;
      color: var(--c-text-main);
    }

    .form-control {
      width: 100%;
      padding: 12px 14px;
      border: 2px solid var(--c-border-strong);
      border-radius: 8px;
      font-size: 0.95rem;
      font-family: inherit;
      background: #f8fafc;
      transition: border-color 0.2s ease, background 0.2s ease;
    }

    .form-control:focus {
      outline: none;
      border-color: var(--c-primary);
      background: #ffffff;
      box-shadow: 0 0 0 3px rgba(29, 78, 216, 0.15);
    }

    textarea.form-control {
      min-height: 110px;
      resize: vertical;
    }

    .btn-submit {
      width: 100%;
      padding: 14px;
      background: #16a34a;
      color: #ffffff;
      font-size: 1.1rem;
      font-weight: 800;
      border: 2px solid var(--c-border-strong);
      border-radius: 8px;
      box-shadow: var(--shadow-pop);
      cursor: pointer;
      transition: all 0.15s ease;
    }

    .btn-submit:hover {
      background: #15803d;
      transform: translate(-2px, -2px);
      box-shadow: var(--shadow-pop-lg);
    }

    /* FAQ Section */
    .faq-list {
      max-width: 880px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: #ffffff;
      border: 2px solid var(--c-border-strong);
      border-radius: 8px;
      box-shadow: var(--shadow-pop-sm);
      overflow: hidden;
    }

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 16px 20px;
      background: #ffffff;
      border: none;
      font-size: 1rem;
      font-weight: 800;
      color: var(--c-text-main);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }

    .faq-question:hover {
      background: #f8fafc;
    }

    .faq-answer {
      padding: 0 20px 16px;
      color: var(--c-text-muted);
      font-size: 0.92rem;
      line-height: 1.65;
      display: none;
      border-top: 1px dashed var(--c-border);
      margin-top: 4px;
      padding-top: 12px;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

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

    .faq-icon {
      font-size: 1.25rem;
      transition: transform 0.2s ease;
      font-weight: 800;
      line-height: 1;
    }

    /* Testimonials */
    .review-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
      gap: 20px;
    }

    .review-card {
      background: #ffffff;
      border: 2px solid var(--c-border-strong);
      border-radius: var(--radius-box);
      padding: 20px;
      box-shadow: var(--shadow-pop-sm);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
    }

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

    .review-avatar {
      width: 44px;
      height: 44px;
      background: #fed7aa;
      border: 2px solid var(--c-border-strong);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 0.9rem;
    }

    .review-author {
      font-weight: 800;
      font-size: 0.95rem;
    }

    .review-role {
      font-size: 0.8rem;
      color: var(--c-text-muted);
    }

    .review-quote {
      font-size: 0.9rem;
      color: #334155;
      line-height: 1.6;
      margin-bottom: 12px;
      font-style: normal;
    }

    .review-stars {
      color: #f59e0b;
      font-size: 0.9rem;
      letter-spacing: 2px;
    }

    /* Articles & Links */
    .article-box {
      background: #f8fafc;
      border: 2px dashed var(--c-border-strong);
      border-radius: var(--radius-box);
      padding: 24px;
      margin-bottom: 24px;
    }

    .article-links-row {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 12px;
    }

    .article-link-chip {
      background: #ffffff;
      border: 1.5px solid var(--c-border-strong);
      padding: 8px 14px;
      border-radius: 6px;
      text-decoration: none;
      color: var(--c-text-main);
      font-size: 0.88rem;
      font-weight: 700;
      box-shadow: 1.5px 1.5px 0px var(--c-border-strong);
      transition: all 0.15s ease;
    }

    .article-link-chip:hover {
      background: #fef08a;
      transform: translateY(-2px);
    }

    /* Footer */
    footer.site-footer {
      background: #ffffff;
      border-top: 3px solid var(--c-border-strong);
      padding: 48px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.2fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 36px;
    }

    .footer-col h4 {
      font-size: 1.05rem;
      font-weight: 800;
      margin-bottom: 16px;
      color: var(--c-text-main);
      border-left: 4px solid var(--c-accent-coral);
      padding-left: 8px;
    }

    .footer-col p {
      font-size: 0.88rem;
      color: var(--c-text-muted);
      line-height: 1.7;
      margin-bottom: 8px;
    }

    .qr-box {
      display: flex;
      align-items: center;
      gap: 16px;
      margin-top: 12px;
      background: #f8fafc;
      padding: 12px;
      border: 2px solid var(--c-border-strong);
      border-radius: 8px;
      width: fit-content;
    }

    .qr-box img {
      width: 76px;
      height: 76px;
      display: block;
      border: 1px solid var(--c-border);
    }

    .qr-text {
      font-size: 0.82rem;
      color: var(--c-text-muted);
      line-height: 1.4;
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
    }

    .friend-links a {
      color: var(--c-text-main);
      text-decoration: none;
      font-size: 0.85rem;
      font-weight: 600;
      background: #f1f5f9;
      padding: 4px 8px;
      border-radius: 4px;
      border: 1px solid var(--c-border);
      transition: all 0.2s;
    }

    .friend-links a:hover {
      background: #fee2e2;
      color: #991b1b;
    }

    .footer-bottom {
      border-top: 2px solid var(--c-border);
      padding-top: 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 12px;
      font-size: 0.85rem;
      color: var(--c-text-muted);
    }

    .footer-bottom a {
      color: var(--c-text-main);
      font-weight: 700;
      text-decoration: none;
    }

    /* Floating Widget */
    .float-widget {
      position: fixed;
      right: 24px;
      bottom: 24px;
      z-index: 999;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }

    .float-btn {
      width: 48px;
      height: 48px;
      background: #ffffff;
      border: 2px solid var(--c-border-strong);
      border-radius: 50%;
      box-shadow: var(--shadow-pop-sm);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.1rem;
      cursor: pointer;
      text-decoration: none;
      color: var(--c-text-main);
      transition: transform 0.15s ease;
    }

    .float-btn:hover {
      transform: scale(1.08);
      background: #fef08a;
    }

    /* Responsive */
    @media (max-width: 992px) {
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
        gap: 28px;
      }
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: #ffffff;
        flex-direction: column;
        padding: 16px;
        border-bottom: 3px solid var(--c-border-strong);
      }
      .nav-links.show {
        display: flex;
      }
      .nav-toggle {
        display: block;
      }
      .form-row {
        grid-template-columns: 1fr;
      }
      .hero-content h1 {
        font-size: 1.8rem;
      }
    }