html { scroll-behavior: smooth; }
    @import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700;800&family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

    :root {
      --bg: #030712;
      --panel: rgba(17, 24, 39, 0.7);
      --panel-solid: #111827;
      --border: rgba(255, 255, 255, 0.08);
      --text: #f3f4f6;
      --text-muted: #9ca3af;
      --primary: #6366f1; /* Indigo */
      --primary-hover: #4f46e5;
      --accent: #ec4899; /* Pink */
      --accent-rgb: 236, 72, 153;
      --success: #10b981;
      --glow-color: rgba(99, 102, 241, 0.15);
      --radius: 16px;
      --radius-sm: 8px;
      --font-sans: 'Outfit', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    }

    [data-theme="light"] {
      --bg: #f8fafc;
      --panel: rgba(255, 255, 255, 0.8);
      --panel-solid: #ffffff;
      --border: rgba(15, 23, 42, 0.08);
      --text: #0f172a;
      --text-muted: #64748b;
      --primary: #4f46e5;
      --primary-hover: #3730a3;
      --accent: #db2777;
      --accent-rgb: 219, 39, 119;
      --success: #059669;
      --glow-color: rgba(79, 70, 229, 0.08);
    }

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

    body {
      background-color: var(--bg);
      color: var(--text);
      font-family: var(--font-sans);
      line-height: 1.5;
      overflow-x: hidden;
      transition: background-color 0.3s ease, color 0.3s ease;
      position: relative;
    }

    /* Ambient Background Blobs (Dark mode premium feel) */
    .ambient-bg {
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      height: 900px;
      pointer-events: none;
      z-index: -1;
      overflow: hidden;
    }
    .blob {
      position: absolute;
      border-radius: 50%;
      filter: blur(120px);
      opacity: 0.12;
      mix-blend-mode: screen;
      animation: float 20s infinite alternate;
    }
    [data-theme="light"] .blob {
      opacity: 0.06;
      mix-blend-mode: multiply;
    }
    .blob-1 {
      width: 400px;
      height: 400px;
      background: var(--primary);
      top: -100px;
      left: 10%;
    }
    .blob-2 {
      width: 500px;
      height: 500px;
      background: var(--accent);
      top: 150px;
      right: 10%;
      animation-delay: -5s;
    }

    @keyframes float {
      0% { transform: translate(0, 0) scale(1); }
      100% { transform: translate(60px, 40px) scale(1.1); }
    }

    /* Navigation */
    header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: color-mix(in srgb, var(--bg) 70%, transparent);
      backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border);
      padding: 16px 40px;
    }
    .nav-container {
      max-width: 1280px;
      margin: 0 auto;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      text-decoration: none;
      color: var(--text);
      font-weight: 800;
      font-size: 22px;
      letter-spacing: -0.03em;
    }
    .logo svg {
      width: 32px;
      height: 32px;
      color: var(--primary);
    }
    .logo span {
      background: linear-gradient(135deg, var(--primary), var(--accent)) !important;
      -webkit-background-clip: text !important;
      background-clip: text !important;
      -webkit-text-fill-color: transparent !important;
      color: transparent !important;
      display: inline-block !important;
    }
    nav {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    nav a {
      color: var(--text);
      text-decoration: none;
      font-size: 14.5px;
      font-weight: 600;
      transition: color 0.2s;
    }
    nav a:hover {
      color: var(--primary);
    }
    .nav-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .btn {
      padding: 9px 20px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 14px;
      cursor: pointer;
      transition: all 0.2s ease;
      text-decoration: none;
      border: none;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--border);
      color: var(--text);
    }
    .btn-outline:hover {
      background: rgba(255, 255, 255, 0.05);
      border-color: var(--primary);
      color: var(--primary);
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--primary), var(--primary-hover));
      color: #ffffff;
      box-shadow: 0 4px 14px 0 rgba(99, 102, 241, 0.3);
    }
    .btn-primary:hover {
      transform: translateY(-1px);
      box-shadow: 0 6px 20px 0 rgba(99, 102, 241, 0.4);
    }
    .theme-btn {
      background: none;
      border: 1px solid var(--border);
      width: 38px;
      height: 38px;
      border-radius: 50%;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--text);
      transition: all 0.2s;
    }
    .theme-btn:hover {
      border-color: var(--primary);
      color: var(--primary);
    }

    /* Hero Section */
    .hero {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      /* 上下留白在HTML标签内联style中单独设置 */
      text-align: center;
    }
    .badge-hero {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      padding: 6px 14px;
      border-radius: 99px;
      background: rgba(99, 102, 241, 0.1);
      border: 1px solid rgba(99, 102, 241, 0.2);
      color: var(--primary);
      font-size: 13.5px;
      font-weight: 600;
      margin-bottom: 24px;
    }
    .hero h1 {
      font-size: 56px;
      font-weight: 800;
      line-height: 1.15;
      letter-spacing: -0.02em;
      margin-bottom: 24px;
    }
    .hero h1 span {
      background: linear-gradient(135deg, var(--primary) 20%, var(--accent) 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .hero p {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 760px;
      margin: 0 auto 36px auto;
    }
    .hero-ctas {
      display: flex;
      justify-content: center;
      gap: 16px;
    }

    /* Stats Grid */
    .stats-section {
      background: var(--panel);
      backdrop-filter: blur(12px);
      border-top: 1px solid var(--border);
      border-bottom: 1px solid var(--border);
      padding: 40px 24px;
      margin-top: 20px;
    }
    .stats-grid {
      max-width: 1280px;
      margin: 0 auto;
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 32px;
      text-align: center;
    }
    .stat-card h3 {
      font-size: 42px;
      font-weight: 800;
      margin-bottom: 8px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .stat-card p {
      font-size: 14.5px;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* Services Grid */
    .section-title {
      text-align: center;
      margin-bottom: 24px;
      padding: 0 24px;
    }
    .section-title h2 {
      font-size: 36px;
      font-weight: 800;
      letter-spacing: -0.02em;
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--text-muted);
      font-size: 16px;
      max-width: 600px;
      margin: 0 auto;
    }
    .main-container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .services-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
      gap: 24px;
      margin-bottom: 60px;
    }
    .service-card {
      background: var(--panel);
      backdrop-filter: blur(12px);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 36px;
      transition: all 0.3s;
      position: relative;
      overflow: hidden;
    }
    .service-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 4px;
      height: 100%;
      background: var(--primary);
      opacity: 0;
      transition: opacity 0.3s;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 12px 30px var(--glow-color);
      border-color: rgba(99, 102, 241, 0.2);
    }
    .service-card:hover::before {
      opacity: 1;
    }
    .service-icon {
      width: 48px;
      height: 48px;
      border-radius: var(--radius-sm);
      background: rgba(99, 102, 241, 0.1);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      margin-bottom: 24px;
    }
    .service-card h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 12px;
    }
    .service-card p {
      color: var(--text-muted);
      font-size: 14.5px;
      line-height: 1.6;
    }

    /* AI Terminal Diagnosis */
    .terminal-section {
      background: #000000;
      border: 1px solid rgba(255, 255, 255, 0.15);
      border-radius: var(--radius);
      max-width: 900px;
      margin: 40px auto;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0, 0, 0, 0.6);
    }
    .terminal-header {
      background: #111;
      padding: 12px 20px;
      border-bottom: 1px solid rgba(255, 255, 255, 0.1);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .terminal-dots {
      display: flex;
      gap: 6px;
    }
    .dot {
      width: 10px;
      height: 10px;
      border-radius: 50%;
    }
    .dot-red { background: #ff5f56; }
    .dot-yellow { background: #ffbd2e; }
    .dot-green { background: #27c93f; }
    .terminal-title {
      font-size: 12px;
      font-weight: 600;
      color: rgba(255, 255, 255, 0.4);
      font-family: monospace;
    }
    .terminal-inputs {
      padding: 24px;
      background: #09090b;
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
      display: grid;
      grid-template-columns: 1fr 1fr auto;
      gap: 16px;
      align-items: end;
    }
    @media (max-width: 640px) {
      .terminal-inputs {
        grid-template-columns: 1fr;
      }
    }
    .terminal-field {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .terminal-field label {
      font-size: 11px;
      color: rgba(255, 255, 255, 0.5);
      font-family: monospace;
      text-transform: uppercase;
      letter-spacing: 0.05em;
    }
    .terminal-input {
      background: #18181b;
      border: 1px solid rgba(255, 255, 255, 0.1);
      padding: 10px 14px;
      border-radius: 6px;
      color: #fff;
      font-family: monospace;
      font-size: 14px;
      transition: all 0.2s;
    }
    .terminal-input:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
    }
    .terminal-screen {
      height: 320px;
      padding: 20px;
      font-family: monospace;
      font-size: 13.5px;
      line-height: 1.6;
      color: #38bdf8; /* light blue */
      overflow-y: auto;
      background: #09090b;
      display: flex;
      flex-direction: column;
      gap: 8px;
    }
    .term-line {
      word-break: break-all;
    }
    .term-success { color: #4ade80; }
    .term-warning { color: #facc15; }
    .term-error { color: #f87171; }
    .term-system { color: #a1a1aa; }
    .term-highlight { color: #f472b6; }
    
    /* FAQ Section */
    .faq-container {
      max-width: 800px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: var(--panel);
      backdrop-filter: blur(12px);
      border: 1px solid var(--border);
      border-radius: var(--radius-sm);
      overflow: hidden;
      transition: all 0.2s;
    }
    .faq-trigger {
      width: 100%;
      padding: 20px 24px;
      background: none;
      border: none;
      color: var(--text);
      font-family: var(--font-sans);
      font-size: 16px;
      font-weight: 700;
      text-align: left;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      gap: 16px;
    }
    .faq-trigger svg {
      width: 18px;
      height: 18px;
      color: var(--text-muted);
      transition: transform 0.2s;
      flex-shrink: 0;
    }
    .faq-content {
      
      overflow: hidden;
      
      padding: 0 24px;
      color: var(--text-muted);
      font-size: 14.5px;
      line-height: 1.6;
    }
    details[open].faq-item {
      border-color: rgba(99, 102, 241, 0.2);
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
      background: var(--primary-light);
    }
    details[open].faq-item .faq-trigger span {
      font-weight: 700;
      color: var(--primary);
    }
    details[open].faq-item .faq-trigger svg {
      transform: rotate(45deg);
      color: var(--primary);
    }
    details[open].faq-item .faq-content {
      display: block;
      animation: faqSlideDown 0.3s ease-out;
      padding-bottom: 20px;
    }
    summary.faq-trigger {
      list-style: none;
    }
    summary.faq-trigger::-webkit-details-marker {
      display: none;
    }
    @keyframes faqSlideDown {
      from { opacity: 0; transform: translateY(-5px); }
      to { opacity: 1; transform: translateY(0); }
    }

    /* Leads Form Section */
    .leads-section {
      background: var(--panel);
      backdrop-filter: blur(12px);
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 48px;
      max-width: 760px;
      margin: 40px auto;
      box-shadow: 0 10px 30px rgba(0, 0, 0, 0.03);
    }
    .leads-form-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
      margin-bottom: 24px;
    }
    @media (max-width: 640px) {
      .leads-form-grid {
        grid-template-columns: 1fr;
      }
    }
    .form-group {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }
    .form-group label {
      font-size: 13.5px;
      font-weight: 600;
      color: var(--text);
    }
    .form-control {
      width: 100%;
      padding: 11px 14px;
      background: var(--panel-solid);
      border: 1px solid var(--border);
      border-radius: var(--radius-sm);
      color: var(--text);
      font-family: var(--font-sans);
      font-size: 14.5px;
      transition: all 0.2s;
    }
    .form-control:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
    }
    .btn-block {
      width: 100%;
      padding: 13px;
      font-size: 15.5px;
      letter-spacing: 0.02em;
    }

    /* Floating Chat assistant */
    
    
    
    .chat-drawer {
      position: fixed;
      top: 0;
      right: -420px;
      width: 400px;
      height: 100%;
      background: var(--panel-solid);
      border-left: 1px solid var(--border);
      z-index: 300;
      box-shadow: -10px 0 30px rgba(0, 0, 0, 0.3);
      display: flex;
      flex-direction: column;
      transition: right 0.3s cubic-bezier(0.77, 0, 0.175, 1);
    }
    @media (max-width: 480px) {
      .chat-drawer {
        width: 100%;
        right: -100%;
      }
    }
    .chat-drawer.open {
      right: 0;
    }
    
    
    
    .chat-close-btn {
      background: none;
      border: none;
      cursor: pointer;
      color: var(--text-muted);
      display: flex;
      align-items: center;
      justify-content: center;
      width: 32px;
      height: 32px;
      border-radius: 50%;
      transition: all 0.2s;
    }
    .chat-close-btn:hover {
      background: rgba(255, 255, 255, 0.05);
      color: var(--text);
    }
    .chat-close-btn svg {
      width: 16px;
      height: 16px;
    }
    .chat-body {
      flex-grow: 1;
      padding: 20px;
      overflow-y: auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
      background: color-mix(in srgb, var(--bg) 30%, var(--panel-solid));
    }
    
    .msg-bot {
      align-self: flex-start;
      background: var(--panel);
      border: 1px solid var(--border);
      color: var(--text);
      border-top-left-radius: 2px;
    }
    .msg-user {
      align-self: flex-end;
      background: var(--primary);
      color: #ffffff;
      border-top-right-radius: 2px;
    }
    .msg-skeleton {
      display: flex;
      gap: 4px;
      padding: 12px 16px;
      align-items: center;
    }
    .msg-skeleton span {
      width: 6px;
      height: 6px;
      background: var(--text-muted);
      border-radius: 50%;
      animation: bounce 1.4s infinite ease-in-out both;
    }
    .msg-skeleton span:nth-child(1) { animation-delay: -0.32s; }
    .msg-skeleton span:nth-child(2) { animation-delay: -0.16s; }
    @keyframes bounce {
      0%, 80%, 100% { transform: scale(0); }
      40% { transform: scale(1); }
    }
    .chat-footer {
      padding: 16px 20px;
      border-top: 1px solid var(--border);
      display: flex;
      gap: 10px;
      background: var(--bg);
    }
    .chat-input {
      flex-grow: 1;
      border: 1px solid var(--border);
      background: var(--panel-solid);
      color: var(--text);
      padding: 10px 14px;
      border-radius: var(--radius-sm);
      font-family: var(--font-sans);
      font-size: 14px;
    }
    .chat-input:focus {
      outline: none;
      border-color: var(--primary);
    }
    .chat-send-btn {
      background: var(--primary);
      color: #fff;
      border: none;
      padding: 10px 16px;
      border-radius: var(--radius-sm);
      cursor: pointer;
      font-weight: 600;
      transition: background-color 0.2s;
    }
    .chat-send-btn:hover {
      background-color: var(--primary-hover);
    }
    .qid-link {
      display: inline-flex;
      align-items: center;
      padding: 1px 6px;
      border-radius: 4px;
      background: rgba(99, 102, 241, 0.15);
      color: var(--primary);
      text-decoration: none;
      font-weight: 600;
      font-size: 12.5px;
      margin: 0 2px;
      border: 1px solid rgba(99, 102, 241, 0.25);
    }
    .qid-link:hover {
      background: var(--primary);
      color: #fff;
    }

    /* Toast Notification */
    .toast {
      position: fixed;
      top: 30px;
      left: 50%;
      transform: translateX(-50%) translateY(-20px);
      background: #111827;
      color: #fff;
      border: 1px solid rgba(255, 255, 255, 0.1);
      padding: 12px 24px;
      border-radius: 30px;
      font-size: 14.5px;
      font-weight: 600;
      z-index: 1000;
      box-shadow: 0 10px 25px rgba(0, 0, 0, 0.3);
      opacity: 0;
      transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      pointer-events: none;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .toast.show {
      opacity: 1;
      transform: translateX(-50%) translateY(0);
    }
    .toast-success {
      border-color: var(--success);
    }
    
    footer {
      border-top: 1px solid var(--border);
      padding: 40px 24px;
      text-align: center;
      color: var(--text-muted);
      font-size: 13.5px;
      background: var(--bg);
    }
  
    /* Back to Top */
    #back-to-top {
      position: fixed;
      bottom: 30px;
      right: 30px;
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--primary);
      color: white;
      border: none;
      box-shadow: 0 4px 12px rgba(99, 102, 241, 0.4);
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      visibility: hidden;
      transform: translateY(20px);
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      z-index: 1000;
    }
    #back-to-top.visible {
      opacity: 1;
      visibility: visible;
      transform: translateY(0);
    }
    #back-to-top:hover {
      transform: translateY(-3px);
      box-shadow: 0 6px 16px rgba(99, 102, 241, 0.6);
      background: #4f46e5;
    }

  
    /* New 6-Grid Services */
    .service-grid-card {
      background: var(--panel);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 32px;
      transition: all 0.3s ease;
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.03);
    }
    .service-grid-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
      border-color: var(--primary);
    }
    .sg-icon {
      width: 50px;
      height: 50px;
      background: rgba(99, 102, 241, 0.1);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: #6366f1;
    }
    .sg-title {
      font-size: 18px;
      font-weight: 800;
      color: var(--text);
      margin-bottom: 12px;
    }
    .sg-desc {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* AI Ecosystems Tabs */
    .ai-tab-input { display: none; }
    .ai-tabs-header {
      display: flex;
      justify-content: center;
      gap: 32px;
      border-bottom: 1px solid var(--border);
      margin-bottom: 24px;
      overflow-x: auto;
    }
    .ai-tab-label {
      padding: 12px 0;
      font-size: 16px;
      font-weight: 600;
      color: var(--text-muted);
      cursor: pointer;
      position: relative;
      white-space: nowrap;
    }
    .ai-tab-label::after {
      content: '';
      position: absolute;
      bottom: -1px;
      left: 0;
      width: 100%;
      height: 2px;
      background: #6366f1;
      transform: scaleX(0);
      transition: transform 0.3s ease;
    }
    #ai-tab-1:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-1"],
    #ai-tab-2:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-2"],
    #ai-tab-3:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-3"],
    #ai-tab-4:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-4"],
    #ai-tab-5:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-5"] {
      color: #6366f1;
    }
    #ai-tab-1:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-1"]::after,
    #ai-tab-2:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-2"]::after,
    #ai-tab-3:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-3"]::after,
    #ai-tab-4:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-4"]::after,
    #ai-tab-5:checked ~ .ai-tabs-header .ai-tab-label[for="ai-tab-5"]::after {
      transform: scaleX(1);
    }
    .ai-tab-panel {
      display: none !important;
      animation: fadeIn 0.4s ease forwards;
    }
    .ai-tab-panel.active,
    #ai-tab-1:checked ~ .ai-tabs-content #ai-panel-1,
    #ai-tab-2:checked ~ .ai-tabs-content #ai-panel-2,
    #ai-tab-3:checked ~ .ai-tabs-content #ai-panel-3,
    #ai-tab-4:checked ~ .ai-tabs-content #ai-panel-4,
    #ai-tab-5:checked ~ .ai-tabs-content #ai-panel-5 {
      display: block !important;
    }

    /* Dynamic Cases Scroll Container */
    .cases-scroll-container {
      display: flex;
      overflow-x: auto;
      scroll-snap-type: x mandatory;
      gap: 1.5rem;
      padding-bottom: 20px;
      -ms-overflow-style: none;
      scrollbar-width: none;
    }
    .cases-scroll-container::-webkit-scrollbar {
      display: none;
    }
    .case-card-item {
      flex: 0 0 100%;
      scroll-snap-align: start;
    }
    @media (min-width: 768px) {
      .case-card-item {
        flex: 0 0 calc(33.333% - 16px);
      }
    }

    /* Tailwind utility fallbacks & robust tab display helpers */
    .hidden { display: none; }
    .flex { display: flex; }
    .goal-content.hidden { display: none !important; }
    .goal-content.flex { display: flex !important; }