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

    :root {
      --color-bg: #f8fafc;
      --color-surface: #ffffff;
      --color-text: #1e293b;
      --color-text-light: #475569;
      --color-primary: #4f46e5;
      --color-primary-light: #c7d2fe;
      --color-accent: #06b6d4;
      --color-accent-soft: #cffafe;
      --color-glow: #a78bfa;
      --color-border: #e2e8f0;
      --color-shadow: rgba(79, 70, 229, 0.08);
      --gradient-brand: linear-gradient(135deg, #4f46e5 0%, #06b6d4 50%, #a78bfa 100%);
      --gradient-soft: linear-gradient(135deg, #eef2ff 0%, #ecfeff 100%);
      --radius-card: 1.5rem;
      --radius-btn: 2rem;
      --font: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font);
      background: var(--color-bg);
      color: var(--color-text);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* ===== Header ===== */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--color-border);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 4rem;
      gap: 1rem;
    }

    .brand {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      flex-shrink: 0;
    }

    .brand img {
      height: 2rem;
      width: auto;
    }

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

    .nav-links li {
      margin: 0;
    }

    .nav-links a {
      display: inline-block;
      padding: 0.5rem 0.9rem;
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--color-text-light);
      text-decoration: none;
      border-radius: 0.5rem;
      transition: color 0.2s, background 0.2s;
    }

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

    .header-cta {
      display: none;
      align-items: center;
      gap: 0.75rem;
    }

    .btn-outline {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.5rem 1.2rem;
      font-size: 0.9rem;
      font-weight: 600;
      border-radius: var(--radius-btn);
      border: 1.5px solid var(--color-primary);
      color: var(--color-primary);
      background: transparent;
      text-decoration: none;
      transition: all 0.25s;
    }

    .btn-outline:hover {
      background: var(--color-primary);
      color: #fff;
      box-shadow: 0 4px 14px var(--color-shadow);
    }

    .btn-solid {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.55rem 1.4rem;
      font-size: 0.9rem;
      font-weight: 600;
      border-radius: var(--radius-btn);
      border: none;
      background: var(--gradient-brand);
      color: #fff;
      text-decoration: none;
      cursor: pointer;
      transition: transform 0.2s, box-shadow 0.25s;
      box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
    }

    .btn-solid:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 24px rgba(79, 70, 229, 0.4);
    }

    .mobile-menu-btn {
      display: flex;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 0.5rem;
    }

    .mobile-menu-btn span {
      display: block;
      width: 24px;
      height: 2px;
      background: var(--color-text);
      border-radius: 2px;
      transition: transform 0.2s;
    }

    .mobile-nav {
      display: none;
      background: #fff;
      border-bottom: 1px solid var(--color-border);
      padding: 0.5rem 1.5rem 1rem;
    }

    .mobile-nav.open {
      display: block;
    }

    .mobile-nav a {
      display: block;
      padding: 0.65rem 0;
      font-size: 0.95rem;
      color: var(--color-text);
      text-decoration: none;
      border-bottom: 1px solid var(--color-border);
    }

    .mobile-nav a:last-child {
      border-bottom: none;
    }

    /* ===== Hero (no image) ===== */
    .hero {
      position: relative;
      overflow: hidden;
      background: var(--gradient-soft);
      padding: 3rem 0 4rem;
    }

    .hero::before {
      content: '';
      position: absolute;
      top: -30%;
      right: -10%;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle, rgba(79, 70, 229, 0.12) 0%, transparent 70%);
      border-radius: 50%;
      pointer-events: none;
    }

    .hero::after {
      content: '';
      position: absolute;
      bottom: -20%;
      left: -8%;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(6, 182, 212, 0.1) 0%, transparent 70%);
      border-radius: 50%;
      pointer-events: none;
    }

    .hero-inner {
      position: relative;
      z-index: 2;
      text-align: center;
      max-width: 860px;
      margin: 0 auto;
    }

    .hero-badge {
      display: inline-block;
      padding: 0.35rem 1.1rem;
      font-size: 0.8rem;
      font-weight: 600;
      letter-spacing: 0.03em;
      color: var(--color-primary);
      background: rgba(79, 70, 229, 0.1);
      border-radius: 2rem;
      margin-bottom: 1.2rem;
    }

    .hero h1 {
      font-size: 2.2rem;
      font-weight: 800;
      line-height: 1.25;
      letter-spacing: -0.02em;
      margin-bottom: 1rem;
      background: var(--gradient-brand);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-desc {
      font-size: 1.05rem;
      color: var(--color-text-light);
      max-width: 640px;
      margin: 0 auto 1.8rem;
    }

    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: center;
      gap: 1rem;
      margin-bottom: 2.5rem;
    }

    .hero-actions .btn-solid {
      padding: 0.8rem 2.2rem;
      font-size: 1rem;
    }

    .hero-actions .btn-outline {
      padding: 0.8rem 2rem;
      font-size: 1rem;
    }

    .hero-stats {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 1.2rem 2.5rem;
    }

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

    .hero-stat strong {
      display: block;
      font-size: 1.6rem;
      font-weight: 800;
      color: var(--color-primary);
      line-height: 1.2;
    }

    .hero-stat span {
      font-size: 0.85rem;
      color: var(--color-text-light);
    }

    /* ===== Section common ===== */
    .section {
      padding: 3.5rem 0;
    }

    .section-header {
      text-align: center;
      max-width: 640px;
      margin: 0 auto 2.5rem;
    }

    .section-header h2 {
      font-size: 1.75rem;
      font-weight: 700;
      letter-spacing: -0.01em;
      margin-bottom: 0.6rem;
      color: var(--color-text);
    }

    .section-header p {
      color: var(--color-text-light);
      font-size: 0.95rem;
    }

    .section-alt {
      background: var(--color-surface);
    }

    /* ===== Feature cards ===== */
    .feature-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 1.2rem;
    }

    .feature-card {
      background: var(--color-surface);
      border: 1px solid var(--color-border);
      border-radius: var(--radius-card);
      padding: 1.5rem;
      transition: transform 0.25s, box-shadow 0.3s;
    }

    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 12px 30px var(--color-shadow);
    }

    .feature-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 2.6rem;
      height: 2.6rem;
      border-radius: 0.9rem;
      background: var(--gradient-soft);
      font-size: 1.3rem;
      margin-bottom: 1rem;
    }

    .feature-card h3 {
      font-size: 1.05rem;
      font-weight: 600;
      margin-bottom: 0.4rem;
    }

    .feature-card p {
      font-size: 0.88rem;
      color: var(--color-text-light);
    }

    /* ===== Steps ===== */
    .steps {
      display: flex;
      flex-wrap: wrap;
      gap: 1rem;
      counter-reset: step;
    }

    .step-item {
      flex: 1 1 200px;
      background: var(--color-surface);
      border-radius: var(--radius-card);
      padding: 1.5rem;
      border: 1px solid var(--color-border);
      position: relative;
      counter-increment: step;
    }

    .step-item::before {
      content: counter(step, decimal-leading-zero);
      display: inline-block;
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--color-primary);
      opacity: 0.25;
      line-height: 1;
      margin-bottom: 0.6rem;
    }

    .step-item h3 {
      font-size: 1rem;
      font-weight: 600;
      margin-bottom: 0.3rem;
    }

    .step-item p {
      font-size: 0.85rem;
      color: var(--color-text-light);
    }

    /* ===== Comparison ===== */
    .compare-wrap {
      display: grid;
      grid-template-columns: 1fr;
      gap: 1.5rem;
    }

    .compare-rating {
      background: var(--color-surface);
      border-radius: var(--radius-card);
      padding: 2rem;
      border: 1px solid var(--color-border);
      text-align: center;
    }

    .compare-rating .stars {
      font-size: 1.8rem;
      letter-spacing: 0.2rem;
      color: #f59e0b;
      margin-bottom: 0.5rem;
    }

    .compare-rating .score {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--color-primary);
      line-height: 1;
    }

    .compare-rating .score small {
      font-size: 1rem;
      font-weight: 500;
      color: var(--color-text-light);
    }

    .compare-rating p {
      font-size: 0.9rem;
      color: var(--color-text-light);
      margin-top: 0.5rem;
    }

    .compare-table-wrap {
      overflow-x: auto;
      border-radius: var(--radius-card);
      border: 1px solid var(--color-border);
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      font-size: 0.9rem;
      background: var(--color-surface);
      min-width: 480px;
    }

    .compare-table th,
    .compare-table td {
      padding: 0.9rem 1.2rem;
      text-align: left;
      border-bottom: 1px solid var(--color-border);
    }

    .compare-table th {
      background: var(--gradient-soft);
      font-weight: 600;
      color: var(--color-text);
    }

    .compare-table td:first-child {
      font-weight: 500;
    }

    .compare-table tr:last-child td {
      border-bottom: none;
    }

    /* ===== Testimonials ===== */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 1.2rem;
    }

    .testimonial-card {
      background: var(--color-surface);
      border-radius: var(--radius-card);
      padding: 1.5rem;
      border: 1px solid var(--color-border);
      transition: box-shadow 0.25s;
    }

    .testimonial-card:hover {
      box-shadow: 0 8px 24px var(--color-shadow);
    }

    .testimonial-card .quote {
      font-size: 0.92rem;
      color: var(--color-text-light);
      margin-bottom: 1rem;
      line-height: 1.55;
    }

    .testimonial-user {
      display: flex;
      align-items: center;
      gap: 0.7rem;
    }

    .testimonial-avatar {
      width: 2.2rem;
      height: 2.2rem;
      border-radius: 50%;
      background: var(--gradient-soft);
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.9rem;
      font-weight: 700;
      color: var(--color-primary);
    }

    .testimonial-user strong {
      display: block;
      font-size: 0.85rem;
      font-weight: 600;
    }

    .testimonial-user span {
      font-size: 0.78rem;
      color: var(--color-text-light);
    }

    /* ===== FAQ ===== */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 0.7rem;
    }

    .faq-item {
      background: var(--color-surface);
      border: 1px solid var(--color-border);
      border-radius: 1rem;
      overflow: hidden;
    }

    .faq-question {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      padding: 1rem 1.3rem;
      font-size: 0.95rem;
      font-weight: 500;
      text-align: left;
      background: transparent;
      border: none;
      cursor: pointer;
      color: var(--color-text);
      transition: background 0.2s;
    }

    .faq-question:hover {
      background: var(--gradient-soft);
    }

    .faq-question .arrow {
      font-size: 0.8rem;
      transition: transform 0.25s;
      color: var(--color-text-light);
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
    }

    .faq-answer-inner {
      padding: 0 1.3rem 1rem;
      font-size: 0.88rem;
      color: var(--color-text-light);
    }

    /* ===== Form ===== */
    .form-card {
      background: var(--color-surface);
      border-radius: var(--radius-card);
      padding: 2rem;
      border: 1px solid var(--color-border);
      max-width: 680px;
      margin: 0 auto;
    }

    .form-group {
      margin-bottom: 1rem;
    }

    .form-group label {
      display: block;
      font-size: 0.85rem;
      font-weight: 500;
      margin-bottom: 0.3rem;
      color: var(--color-text);
    }

    .form-group input,
    .form-group select,
    .form-group textarea {
      width: 100%;
      padding: 0.7rem 0.9rem;
      font-size: 0.9rem;
      font-family: var(--font);
      border: 1px solid var(--color-border);
      border-radius: 0.8rem;
      background: var(--color-bg);
      color: var(--color-text);
      outline: none;
      transition: border-color 0.2s, box-shadow 0.2s;
    }

    .form-group input:focus,
    .form-group select:focus,
    .form-group textarea:focus {
      border-color: var(--color-primary);
      box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.12);
    }

    .form-group textarea {
      resize: vertical;
      min-height: 80px;
    }

    .form-submit {
      width: 100%;
      padding: 0.8rem;
      font-size: 1rem;
      font-weight: 600;
      border: none;
      border-radius: var(--radius-btn);
      background: var(--gradient-brand);
      color: #fff;
      cursor: pointer;
      transition: transform 0.2s, box-shadow 0.25s;
      box-shadow: 0 4px 14px rgba(79, 70, 229, 0.3);
    }

    .form-submit:hover {
      transform: translateY(-2px);
      box-shadow: 0 8px 24px rgba(79, 70, 229, 0.4);
    }

    /* ===== Footer ===== */
    .site-footer {
      background: #0f172a;
      color: #e2e8f0;
      padding: 2.5rem 0 1.5rem;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1fr;
      gap: 1.8rem;
    }

    .footer-brand img {
      height: 1.8rem;
      margin-bottom: 0.6rem;
      
    }

    .footer-brand p {
      font-size: 0.85rem;
      color: #94a3b8;
      max-width: 280px;
    }

    .footer-col h4 {
      font-size: 0.9rem;
      font-weight: 600;
      margin-bottom: 0.6rem;
      color: #f1f5f9;
    }

    .footer-col ul {
      list-style: none;
    }

    .footer-col li {
      margin-bottom: 0.35rem;
    }

    .footer-col a {
      font-size: 0.82rem;
      color: #94a3b8;
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer-col a:hover {
      color: #c7d2fe;
    }

    .footer-contact p {
      font-size: 0.82rem;
      color: #94a3b8;
      margin-bottom: 0.3rem;
    }

    .footer-contact strong {
      color: #e2e8f0;
    }

    .footer-bottom {
      border-top: 1px solid #1e293b;
      margin-top: 1.8rem;
      padding-top: 1rem;
      text-align: center;
      font-size: 0.78rem;
      color: #64748b;
    }

    .friend-links {
      display: flex;
      flex-wrap: wrap;
      gap: 0.4rem 0.9rem;
      margin-top: 0.5rem;
    }

    .friend-links a {
      font-size: 0.78rem;
      color: #64748b;
      text-decoration: none;
    }

    .friend-links a:hover {
      color: #c7d2fe;
    }

    /* ===== Floating ===== */
    .float-actions {
      position: fixed;
      right: 1rem;
      bottom: 1.5rem;
      display: flex;
      flex-direction: column;
      gap: 0.6rem;
      z-index: 200;
    }

    .float-btn {
      width: 2.8rem;
      height: 2.8rem;
      border-radius: 50%;
      border: none;
      background: var(--color-surface);
      box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      font-size: 1.1rem;
      color: var(--color-primary);
      transition: transform 0.2s, box-shadow 0.2s;
      text-decoration: none;
    }

    .float-btn:hover {
      transform: scale(1.08);
      box-shadow: 0 6px 20px rgba(0, 0, 0, 0.18);
    }

    /* ===== Article / news ===== */
    .article-list {
      display: flex;
      flex-direction: column;
      gap: 0.7rem;
    }

    .article-item {
      display: flex;
      align-items: center;
      gap: 0.8rem;
      padding: 0.8rem 1rem;
      background: var(--color-surface);
      border: 1px solid var(--color-border);
      border-radius: 1rem;
      transition: box-shadow 0.2s;
    }

    .article-item:hover {
      box-shadow: 0 4px 14px var(--color-shadow);
    }

    .article-item .dot {
      width: 0.5rem;
      height: 0.5rem;
      border-radius: 50%;
      background: var(--gradient-brand);
      flex-shrink: 0;
    }

    .article-item a {
      font-size: 0.88rem;
      color: var(--color-text);
      text-decoration: none;
    }

    .article-item a:hover {
      color: var(--color-primary);
    }

    /* ===== Tags cloud ===== */
    .tag-cloud {
      display: flex;
      flex-wrap: wrap;
      gap: 0.5rem;
    }

    .tag-cloud span {
      display: inline-block;
      padding: 0.3rem 0.8rem;
      font-size: 0.8rem;
      border-radius: 2rem;
      background: var(--color-surface);
      border: 1px solid var(--color-border);
      color: var(--color-text-light);
      transition: all 0.2s;
    }

    .tag-cloud span:hover {
      border-color: var(--color-primary);
      color: var(--color-primary);
    }

    /* ===== Responsive ===== */
    @media (min-width: 768px) {
      .nav-links {
        display: flex;
      }
      .header-cta {
        display: flex;
      }
      .mobile-menu-btn {
        display: none;
      }
      .hero h1 {
        font-size: 2.8rem;
      }
      .section {
        padding: 4.5rem 0;
      }
      .section-header h2 {
        font-size: 2rem;
      }
      .compare-wrap {
        grid-template-columns: 280px 1fr;
        align-items: start;
      }
      .footer-grid {
        grid-template-columns: 1.2fr 1fr 1fr 1fr;
      }
    }

    @media (min-width: 1024px) {
      .hero {
        padding: 4.5rem 0 5rem;
      }
      .hero h1 {
        font-size: 3.2rem;
      }
    }

    /* Reveal animation */
    .reveal {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.6s ease, transform 0.6s ease;
    }

    .reveal.visible {
      opacity: 1;
      transform: translateY(0);
    }

    @media (prefers-reduced-motion: reduce) {
      .reveal {
        opacity: 1;
        transform: none;
        transition: none;
      }
      * {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
      }
    }