/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-dark: #3A56D4;
      --primary-light: #6B8AFF;
      --green: #00B578;
      --orange: #FF9F0A;
      --red: #FA5151;
      --bg: #F5F6FA;
      --card: #FFFFFF;
      --text: #1F2329;
      --text-secondary: #86909C;
      --border: #E5E8EF;
      --shadow-sm: 0 2px 8px rgba(31, 35, 41, 0.04);
      --shadow-md: 0 4px 16px rgba(31, 35, 41, 0.08);
      --shadow-lg: 0 16px 48px rgba(31, 35, 41, 0.16);
      --radius-sm: 8px;
      --radius: 12px;
      --radius-pill: 24px;
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      --ease-out: cubic-bezier(0.4, 0, 0.2, 1);
      --transition-fast: 150ms;
      --transition-smooth: 250ms;
      --transition-slow: 300ms;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
      transition: all var(--transition-smooth) var(--ease-out);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      white-space: nowrap;
    }
    .container {
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
      line-height: 1.3;
    }
    h1 { font-size: 36px; font-weight: 700; letter-spacing: -0.02em; }
    h2 { font-size: 28px; margin-bottom: 48px; text-align: center; }
    h3 { font-size: 20px; }
    p { font-size: 16px; color: var(--text); }
    .text-secondary { color: var(--text-secondary); font-size: 14px; }
    .caption { font-size: 12px; color: var(--text-secondary); }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      transition: box-shadow var(--transition-smooth), background var(--transition-smooth);
      height: 72px;
      display: flex;
      align-items: center;
    }
    .header.scrolled {
      box-shadow: 0 1px 0 rgba(31,35,41,0.06);
      background: rgba(255,255,255,0.98);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--text);
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: -0.02em;
    }
    .logo::before {
      content: "";
      display: inline-block;
      width: 28px;
      height: 28px;
      background: var(--primary);
      border-radius: 8px;
      opacity: 0.9;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 16px;
      color: var(--text-secondary);
      transition: color var(--transition-fast);
      font-weight: 500;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a.active::after {
      content: "";
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 500;
      font-size: 16px;
      box-shadow: 0 2px 8px rgba(78,110,242,0.2);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 4px 12px rgba(78,110,242,0.3);
      transform: scale(1.02);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 1px solid var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 500;
    }
    .btn-outline:hover {
      background: rgba(78,110,242,0.04);
      border-color: var(--primary-dark);
      color: var(--primary-dark);
    }
    .btn-white {
      background: white;
      color: var(--primary);
      border: 1px solid white;
    }
    .btn-white:hover {
      background: #f0f2ff;
    }
    .btn-ghost {
      background: transparent;
      color: white;
      border: 1px solid rgba(255,255,255,0.5);
      padding: 12px 28px;
      border-radius: var(--radius-sm);
    }
    .btn-ghost:hover {
      background: rgba(255,255,255,0.1);
      border-color: white;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      justify-content: space-between;
      width: 24px;
      height: 20px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 100%;
      height: 2px;
      background: var(--text);
      border-radius: 2px;
      transition: all var(--transition-smooth);
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(20px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 36px;
      z-index: 999;
      opacity: 0;
      pointer-events: none;
      transition: opacity var(--transition-slow);
    }
    .mobile-menu.active {
      opacity: 1;
      pointer-events: auto;
    }
    .mobile-menu a {
      font-size: 20px;
      font-weight: 500;
      color: var(--text);
      transition: color var(--transition-fast);
    }
    .mobile-menu .btn-primary {
      margin-top: 20px;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: white;
      padding-top: 72px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 64px;
      align-items: center;
    }
    .hero-content h1 {
      margin-bottom: 24px;
    }
    .hero-content p {
      font-size: 16px;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      position: relative;
      height: 400px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .shape {
      position: absolute;
      border-radius: 40% 60% 30% 70% / 50% 40% 60% 50%;
      background: linear-gradient(135deg, var(--primary), var(--primary-light));
      opacity: 0.15;
      filter: blur(40px);
      animation: float 8s infinite alternate ease-in-out;
    }
    .shape1 {
      width: 250px;
      height: 250px;
      top: 20px;
      right: 40px;
    }
    .shape2 {
      width: 180px;
      height: 180px;
      bottom: 40px;
      left: 20px;
      background: linear-gradient(225deg, #6B8AFF, #A0B4FF);
      animation-duration: 12s;
      opacity: 0.2;
    }
    @keyframes float {
      0% { transform: translate(0, 0) rotate(0deg); }
      100% { transform: translate(15px, -15px) rotate(8deg); }
    }

    /* 通用板块 */
    section {
      padding: 100px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 64px;
    }
    .section-title h2 {
      margin-bottom: 16px;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }

    /* 痛点卡片 */
    .pain-card {
      background: #F8F9FB;
      border-radius: var(--radius);
      padding: 32px;
      border-left: 3px solid var(--primary);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .pain-card .icon {
      width: 36px;
      height: 36px;
      color: var(--primary);
      font-size: 24px;
    }
    .pain-card h4 {
      font-size: 18px;
      font-weight: 600;
    }

    /* 解决方案 */
    .solution-img {
      aspect-ratio: 4 / 3;
      background: #E5E8EF;
      border-radius: var(--radius);
      overflow: hidden;
    }
    .solution-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .solution-text ul {
      list-style: none;
      margin-top: 16px;
    }
    .solution-text li {
      display: flex;
      align-items: flex-start;
      gap: 12px;
      margin-bottom: 12px;
      font-size: 15px;
    }
    .solution-text li::before {
      content: "✓";
      color: var(--green);
      font-weight: bold;
      font-size: 18px;
    }

    /* 数据卡片 */
    .stat-card {
      background: var(--card);
      border-radius: var(--radius);
      padding: 32px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition-smooth);
    }
    .stat-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-label {
      font-size: 16px;
      color: var(--text-secondary);
      margin-top: 8px;
    }

    /* 证言 */
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scroll-snap-type: x mandatory;
      -webkit-overflow-scrolling: touch;
    }
    .testimonial-scroll::-webkit-scrollbar {
      display: none;
    }
    .testimonial-card {
      min-width: 320px;
      background: var(--card);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
      position: relative;
    }
    .testimonial-card::before {
      content: "“";
      font-size: 48px;
      color: rgba(78,110,242,0.15);
      position: absolute;
      top: 16px;
      left: 24px;
      line-height: 1;
    }
    .testimonial-text {
      font-style: italic;
      margin: 24px 0 16px;
    }
    .author {
      font-weight: 600;
      font-size: 14px;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 18px;
      font-weight: 500;
      cursor: pointer;
      transition: color var(--transition-fast);
      width: 100%;
      text-align: left;
      background: none;
      border: none;
    }
    .faq-question:hover {
      color: var(--primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height var(--transition-slow) var(--ease-out);
      color: var(--text-secondary);
      font-size: 16px;
      padding-top: 0;
    }
    .faq-item.active .faq-answer {
      max-height: 300px;
      padding-top: 12px;
    }
    .faq-arrow {
      transition: transform 0.2s;
      font-size: 18px;
    }
    .faq-item.active .faq-arrow {
      transform: rotate(180deg);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #4E6EF2 0%, #6B8AFF 100%);
      color: white;
      text-align: center;
      padding: 80px 24px;
      border-radius: 0;
    }
    .cta-section h2 {
      color: white;
      font-size: 32px;
    }
    .cta-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      margin: 32px 0 16px;
      flex-wrap: wrap;
    }

    /* Footer */
    .footer {
      background: #1F2329;
      color: #86909C;
      padding: 64px 0 32px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #86909C;
      transition: color 0.2s;
    }
    .footer a:hover {
      color: white;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      font-size: 12px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 32px; }
      .grid-3 { grid-template-columns: 1fr 1fr; }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .hero-grid { grid-template-columns: 1fr; gap: 40px; }
      .hero-visual { height: 240px; }
    }
    @media (max-width: 768px) {
      .header { height: 56px; }
      .nav-links, .nav .btn-primary { display: none; }
      .hamburger { display: flex; }
      .mobile-menu { display: flex; }
      h1 { font-size: 28px; }
      h2 { font-size: 22px; }
      section { padding: 64px 0; }
      .container { padding: 0 16px; }
      .grid-3, .grid-2, .grid-4 { grid-template-columns: 1fr; }
      .hero { padding-top: 56px; }
      .hero-buttons { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }