/* ===== CSS Variables & Reset ===== */
    :root {
      --primary: #1E40AF;
      --primary-light: #2563EB;
      --primary-dark: #1E3A8A;
      --accent: #3B82F6;
      --white: #FFFFFF;
      --gray-50: #F9FAFB;
      --gray-100: #F3F4F6;
      --gray-200: #E5E7EB;
      --gray-400: #9CA3AF;
      --gray-600: #4B5563;
      --gray-800: #1F2937;
      --shadow-sm: 0 1px 3px rgba(0,0,0,.08);
      --shadow-md: 0 4px 16px rgba(30,64,175,.12);
      --shadow-lg: 0 8px 32px rgba(30,64,175,.16);
      --radius: 12px;
      --radius-lg: 16px;
      --transition: .25s ease;
      --max-width: 1140px;
    }

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

    html { scroll-behavior: smooth; }

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--gray-800);
      background: var(--white);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    img { max-width: 100%; display: block; }
    a { text-decoration: none; color: inherit; }
    ul { list-style: none; }

    .container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* ===== Buttons ===== */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 14px 28px;
      border-radius: 50px;
      font-size: 16px;
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: all var(--transition);
      min-height: 48px;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-light), var(--primary));
      color: var(--white);
      box-shadow: var(--shadow-md);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary), var(--primary-dark));
      transform: translateY(-2px);
      box-shadow: var(--shadow-lg);
    }

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

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

    .btn-white {
      background: var(--white);
      color: var(--primary);
      box-shadow: var(--shadow-md);
    }

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

    .btn-sm {
      padding: 10px 20px;
      font-size: 14px;
      min-height: 40px;
    }

    /* ===== Section Common ===== */
    section { padding: 64px 0; }

    .section-header {
      text-align: center;
      margin-bottom: 40px;
    }

    .section-tag {
      display: inline-block;
      background: rgba(37, 99, 235, .1);
      color: var(--primary-light);
      font-size: 13px;
      font-weight: 600;
      padding: 4px 14px;
      border-radius: 50px;
      margin-bottom: 12px;
      letter-spacing: .5px;
    }

    .section-title {
      font-size: clamp(24px, 5vw, 32px);
      font-weight: 700;
      color: var(--gray-800);
      margin-bottom: 12px;
    }

    .section-desc {
      font-size: 16px;
      color: var(--gray-600);
      max-width: 560px;
      margin: 0 auto;
    }

    /* ===== Navigation ===== */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255,255,255,.95);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--gray-200);
      box-shadow: var(--shadow-sm);
    }

    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 64px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 18px;
      color: var(--primary);
    }

    .logo-icon {
      width: 36px;
      height: 36px;
      background: linear-gradient(135deg, var(--primary-light), var(--primary));
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--white);
      font-size: 18px;
      font-weight: 800;
    }

    .nav-menu {
      display: none;
      align-items: center;
      gap: 28px;
    }

    .nav-menu a {
      font-size: 15px;
      color: var(--gray-600);
      font-weight: 500;
      transition: color var(--transition);
    }

    .nav-menu a:hover { color: var(--primary); }

    .nav-actions {
      display: none;
      align-items: center;
      gap: 12px;
    }

    .hamburger {
      display: flex;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
    }

    .hamburger span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--gray-800);
      border-radius: 2px;
      transition: all var(--transition);
    }

    .hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
    .hamburger.active span:nth-child(2) { opacity: 0; }
    .hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

    /* Mobile menu drawer */
    .mobile-menu {
      display: none;
      flex-direction: column;
      padding: 16px 20px 24px;
      border-top: 1px solid var(--gray-200);
      background: var(--white);
    }

    .mobile-menu.open { display: flex; }

    .mobile-menu a {
      padding: 12px 0;
      font-size: 16px;
      color: var(--gray-800);
      border-bottom: 1px solid var(--gray-100);
      font-weight: 500;
    }

    .mobile-menu .btn { margin-top: 16px; width: 100%; }

    /* ===== Hero ===== */
    .hero {
      background: linear-gradient(160deg, #EFF6FF 0%, #DBEAFE 40%, #F0F9FF 100%);
      padding: 72px 0 80px;
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: '';
      position: absolute;
      top: -80px;
      right: -80px;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(37,99,235,.12) 0%, transparent 70%);
      border-radius: 50%;
    }

    .hero-content {
      position: relative;
      text-align: center;
      max-width: 720px;
      margin: 0 auto;
    }

    .hero-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: rgba(239, 68, 68, .1);
      color: #DC2626;
      font-size: 13px;
      font-weight: 600;
      padding: 6px 16px;
      border-radius: 50px;
      margin-bottom: 20px;
      animation: pulse 2s infinite;
    }

    @keyframes pulse {
      0%, 100% { opacity: 1; }
      50% { opacity: .75; }
    }

    .hero-badge::before {
      content: '●';
      font-size: 8px;
    }

    .hero h1 {
      font-size: clamp(28px, 7vw, 48px);
      font-weight: 800;
      line-height: 1.25;
      color: var(--primary-dark);
      margin-bottom: 16px;
    }

    .hero h1 span {
      background: linear-gradient(135deg, var(--primary-light), var(--primary));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-sub {
      font-size: clamp(16px, 3vw, 18px);
      color: var(--gray-600);
      margin-bottom: 32px;
      line-height: 1.7;
    }

    .hero-cta {
      display: flex;
      flex-direction: column;
      gap: 12px;
      align-items: center;
      margin-bottom: 40px;
    }

    .hero-stats {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 16px;
      max-width: 480px;
      margin: 0 auto;
    }

    .stat-item {
      background: var(--white);
      border-radius: var(--radius);
      padding: 16px 8px;
      box-shadow: var(--shadow-sm);
    }

    .stat-num {
      font-size: clamp(20px, 4vw, 28px);
      font-weight: 800;
      color: var(--primary);
    }

    .stat-label {
      font-size: 12px;
      color: var(--gray-600);
      margin-top: 4px;
    }

    /* ===== Advantages ===== */
    .advantages { background: var(--gray-50); }

    .cards-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 20px;
    }

    .card {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--gray-200);
      transition: all var(--transition);
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: rgba(37,99,235,.2);
    }

    .card-icon {
      width: 52px;
      height: 52px;
      background: linear-gradient(135deg, rgba(37,99,235,.15), rgba(30,64,175,.08));
      border-radius: 14px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
      margin-bottom: 16px;
    }

    .card h3 {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--gray-800);
    }

    .card p {
      font-size: 15px;
      color: var(--gray-600);
      line-height: 1.65;
    }

    /* ===== Services ===== */
    .services-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 24px;
    }

    .service-card {
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--gray-200);
      transition: all var(--transition);
    }

    .service-card:hover { box-shadow: var(--shadow-md); }

    .service-header {
      padding: 24px;
      color: var(--white);
    }

    .service-header.chong { background: linear-gradient(135deg, #DC2626, #EF4444); }
    .service-header.wen  { background: linear-gradient(135deg, var(--primary-light), var(--primary)); }
    .service-header.bao  { background: linear-gradient(135deg, #059669, #10B981); }

    .service-header h3 {
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 4px;
    }

    .service-header p { font-size: 14px; opacity: .9; }

    .service-body {
      padding: 24px;
      background: var(--white);
    }

    .service-body ul { display: flex; flex-direction: column; gap: 10px; }

    .service-body li {
      display: flex;
      align-items: flex-start;
      gap: 10px;
      font-size: 15px;
      color: var(--gray-600);
    }

    .service-body li::before {
      content: '✓';
      color: var(--primary-light);
      font-weight: 700;
      flex-shrink: 0;
    }

    .disclaimer-box {
      margin-top: 32px;
      background: #FFFBEB;
      border: 1px solid #FDE68A;
      border-radius: var(--radius);
      padding: 16px 20px;
      display: flex;
      gap: 12px;
      align-items: flex-start;
    }

    .disclaimer-box span { font-size: 20px; flex-shrink: 0; }

    .disclaimer-box p {
      font-size: 14px;
      color: #92400E;
      line-height: 1.6;
    }

    /* ===== FAQ ===== */
    .faq { background: var(--gray-50); }

    .faq-list {
      max-width: 720px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .faq-item {
      background: var(--white);
      border-radius: var(--radius);
      border: 1px solid var(--gray-200);
      overflow: hidden;
      transition: box-shadow var(--transition);
    }

    .faq-item.active { box-shadow: var(--shadow-md); border-color: rgba(37,99,235,.25); }

    .faq-question {
      width: 100%;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 16px;
      padding: 18px 20px;
      background: none;
      border: none;
      cursor: pointer;
      text-align: left;
      font-size: 16px;
      font-weight: 600;
      color: var(--gray-800);
      transition: color var(--transition);
    }

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

    .faq-icon {
      width: 28px;
      height: 28px;
      border-radius: 50%;
      background: var(--gray-100);
      display: flex;
      align-items: center;
      justify-content: center;
      flex-shrink: 0;
      transition: all var(--transition);
      font-size: 18px;
      color: var(--primary);
    }

    .faq-item.active .faq-icon {
      background: var(--primary);
      color: var(--white);
      transform: rotate(45deg);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height .35s ease, padding .35s ease;
    }

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

    .faq-answer-inner {
      padding: 0 20px 18px;
      font-size: 15px;
      color: var(--gray-600);
      line-height: 1.7;
    }

    /* ===== Testimonials ===== */
    .testimonials-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 20px;
    }

    .testimonial {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 28px 24px;
      border: 1px solid var(--gray-200);
      position: relative;
    }

    .testimonial::before {
      content: '"';
      position: absolute;
      top: 12px;
      left: 20px;
      font-size: 48px;
      color: rgba(37,99,235,.15);
      font-family: Georgia, serif;
      line-height: 1;
    }

    .stars {
      color: #FBBF24;
      font-size: 16px;
      margin-bottom: 12px;
      letter-spacing: 2px;
    }

    .testimonial-text {
      font-size: 15px;
      color: var(--gray-600);
      line-height: 1.7;
      margin-bottom: 16px;
      padding-top: 8px;
    }

    .testimonial-author {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .author-avatar {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      background: linear-gradient(135deg, var(--primary-light), var(--primary));
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--white);
      font-weight: 700;
      font-size: 16px;
    }

    .author-info strong {
      display: block;
      font-size: 14px;
      color: var(--gray-800);
    }

    .author-info span {
      font-size: 13px;
      color: var(--gray-400);
    }

    /* ===== Form ===== */
    .form-section {
      background: linear-gradient(160deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
      color: var(--white);
    }

    .form-section .section-title { color: var(--white); }
    .form-section .section-desc { color: rgba(255,255,255,.85); }

    .form-wrapper {
      max-width: 640px;
      margin: 0 auto;
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      box-shadow: var(--shadow-lg);
    }

    .form-group {
      margin-bottom: 20px;
    }

    .form-group label {
      display: block;
      font-size: 14px;
      font-weight: 600;
      color: var(--gray-800);
      margin-bottom: 6px;
    }

    .form-group label .required { color: #DC2626; }

    .form-group input,
    .form-group select,
    .form-group textarea {
      width: 100%;
      padding: 12px 16px;
      border: 1.5px solid var(--gray-200);
      border-radius: 10px;
      font-size: 16px;
      color: var(--gray-800);
      background: var(--gray-50);
      transition: border-color var(--transition), box-shadow var(--transition);
      font-family: inherit;
    }

    .form-group input:focus,
    .form-group select:focus,
    .form-group textarea:focus {
      outline: none;
      border-color: var(--primary-light);
      box-shadow: 0 0 0 3px rgba(37,99,235,.15);
      background: var(--white);
    }

    .form-group textarea { resize: vertical; min-height: 90px; }

    .form-row {
      display: grid;
      grid-template-columns: 1fr;
      gap: 20px;
    }

    .form-submit {
      width: 100%;
      margin-top: 8px;
    }

    /* Success toast */
    .toast {
      display: none;
      position: fixed;
      bottom: 24px;
      left: 50%;
      transform: translateX(-50%) translateY(80px);
      background: #059669;
      color: var(--white);
      padding: 16px 28px;
      border-radius: 50px;
      font-size: 15px;
      font-weight: 600;
      box-shadow: var(--shadow-lg);
      z-index: 9999;
      transition: transform .4s ease, opacity .4s ease;
      opacity: 0;
      white-space: nowrap;
    }

    .toast.show {
      display: block;
      transform: translateX(-50%) translateY(0);
      opacity: 1;
    }

    .toast.toast-error {
      background: #DC2626;
    }

    /* ===== Contact CTA ===== */
    .contact-cta {
      text-align: center;
      padding: 48px 0;
      background: var(--gray-50);
    }

    .contact-cards {
      display: grid;
      grid-template-columns: 1fr;
      gap: 16px;
      max-width: 560px;
      margin: 32px auto 0;
    }

    .contact-card {
      display: flex;
      align-items: center;
      gap: 16px;
      background: var(--white);
      border-radius: var(--radius);
      padding: 20px;
      border: 1px solid var(--gray-200);
      transition: all var(--transition);
    }

    .contact-card:hover {
      border-color: var(--primary-light);
      box-shadow: var(--shadow-md);
    }

    .contact-card-icon {
      width: 48px;
      height: 48px;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
      flex-shrink: 0;
    }

    .contact-card-icon.wechat { background: #DCFCE7; }
    .contact-card-icon.xianyu { background: #FEF3C7; }

    .contact-card-info h4 {
      font-size: 16px;
      font-weight: 700;
      color: var(--gray-800);
      margin-bottom: 2px;
    }

    .contact-card-info p {
      font-size: 14px;
      color: var(--gray-600);
    }

    .contact-card-info .id {
      font-weight: 600;
      color: var(--primary);
    }

    /* ===== Footer ===== */
    footer {
      background: var(--gray-800);
      color: rgba(255,255,255,.75);
      padding: 48px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 32px;
      margin-bottom: 32px;
    }

    .footer-brand .logo { color: var(--white); margin-bottom: 12px; }
    .footer-brand p { font-size: 14px; line-height: 1.7; }

    .footer-col h4 {
      color: var(--white);
      font-size: 15px;
      font-weight: 700;
      margin-bottom: 14px;
    }

    .footer-col ul { display: flex; flex-direction: column; gap: 8px; }
    .footer-col li { font-size: 14px; }
    .footer-col a { transition: color var(--transition); }
    .footer-col a:hover { color: var(--white); }

    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,.1);
      padding-top: 20px;
      text-align: center;
      font-size: 13px;
      line-height: 1.7;
    }

    /* ===== Responsive: Tablet+ ===== */
    @media (min-width: 640px) {
      .hero-cta {
        flex-direction: row;
        justify-content: center;
      }

      .cards-grid {
        grid-template-columns: repeat(2, 1fr);
      }

      .services-grid {
        grid-template-columns: repeat(3, 1fr);
      }

      .testimonials-grid {
        grid-template-columns: repeat(3, 1fr);
      }

      .form-row {
        grid-template-columns: 1fr 1fr;
      }

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

      .footer-grid {
        grid-template-columns: 2fr 1fr 1fr;
      }
    }

    @media (min-width: 768px) {
      section { padding: 80px 0; }

      .nav-menu { display: flex; }
      .nav-actions { display: flex; }
      .hamburger { display: none; }

      .cards-grid {
        grid-template-columns: repeat(4, 1fr);
      }
    }

    @media (min-width: 1024px) {
      .hero { padding: 96px 0 100px; }
    }