/* roulang page: index */
:root {
      --primary: #0A1E2F;
      --accent: #F97316;
      --ice: #E2E8F0;
      --glacier: #06B6D4;
      --bg: #F8FAFC;
      --text: #1E293B;
      --text-secondary: #64748B;
      --white: #FFFFFF;
      --radius-lg: 16px;
      --radius-xl: 24px;
      --radius-full: 999px;
      --shadow-sm: 0 4px 20px rgba(10,30,47,0.06);
      --shadow-md: 0 8px 28px rgba(10,30,47,0.1);
      --shadow-lg: 0 12px 32px rgba(10,30,47,0.12);
      --font-heading: 'Inter', 'Noto Sans SC', system-ui, sans-serif;
      --font-body: 'Inter', 'Noto Sans SC', system-ui, sans-serif;
      --transition: all 0.2s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      color: var(--text);
      background-color: var(--bg);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 800;
      letter-spacing: -0.02em;
    }
    h1 {
      font-size: clamp(2.5rem, 5vw, 3.5rem);
      font-weight: 900;
      line-height: 1.2;
    }
    h2 {
      font-size: clamp(1.8rem, 4vw, 2.25rem);
      margin-bottom: 0.75rem;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 700;
      margin-bottom: 0.5rem;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      display: block;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: var(--white);
      border-bottom: 1px solid var(--ice);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
      z-index: 1000;
      box-shadow: 0 1px 8px rgba(10,30,47,0.03);
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 900;
      font-size: 1.6rem;
      color: var(--primary);
      font-family: var(--font-heading);
    }
    .logo i {
      font-size: 2rem;
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-weight: 600;
      color: var(--text);
      padding: 8px 12px;
      border-radius: var(--radius-full);
      transition: var(--transition);
      font-size: 0.95rem;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--accent);
      background: rgba(249,115,22,0.08);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
    }
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .menu-toggle {
        display: block;
      }
      .nav-links.mobile-open {
        display: flex;
        flex-direction: column;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        height: calc(100vh - 72px);
        background: var(--primary);
        align-items: center;
        justify-content: center;
        gap: 32px;
        z-index: 999;
      }
      .nav-links.mobile-open a {
        color: white;
        font-size: 1.4rem;
        background: transparent;
      }
    }

    /* 板块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    /* Hero */
    .hero {
      background: radial-gradient(circle at 20% 30%, #022C43, #0A1E2F);
      position: relative;
      overflow: hidden;
      padding-top: 120px;
      color: white;
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 200 200" opacity="0.08"><path d="M0 0 L40 20 L80 0 L120 30 L160 10 L200 40 L200 200 L0 200 Z" fill="white"/><path d="M0 40 L30 70 L70 50 L110 80 L150 60 L200 100 L200 200 L0 200 Z" fill="white" opacity="0.5"/></svg>');
      background-size: cover;
      pointer-events: none;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 48px;
      position: relative;
      z-index: 1;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      margin-bottom: 20px;
      color: white;
    }
    .hero-text p {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      padding: 14px 32px;
      border-radius: var(--radius-full);
      font-weight: 700;
      font-size: 1rem;
      transition: var(--transition);
      text-align: center;
      cursor: pointer;
      border: none;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      box-shadow: 0 4px 12px rgba(249,115,22,0.4);
    }
    .btn-primary:hover {
      background: #EA580C;
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(249,115,22,0.5);
    }
    .btn-outline {
      border: 2px solid white;
      color: white;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
    }
    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-image img {
      max-height: 400px;
      border-radius: var(--radius-xl);
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    }
    @media (max-width: 768px) {
      .hero .container {
        flex-direction: column;
        text-align: center;
      }
      .hero-text p {
        max-width: 100%;
      }
      .hero-buttons {
        justify-content: center;
      }
    }

    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 40px;
    }
    .feature-card {
      background: var(--white);
      border: 1px solid var(--ice);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-lg);
    }
    .feature-icon {
      font-size: 2.5rem;
      color: var(--accent);
      margin-bottom: 20px;
      transition: transform 0.2s;
    }
    .feature-card:hover .feature-icon {
      transform: scale(1.1);
    }
    @media (max-width: 1024px) {
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 场景交替 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-xl);
      overflow: hidden;
      border: 1px solid var(--ice);
    }
    .scenario-img img {
      width: 100%;
      height: auto;
    }
    .scenario-text {
      flex: 1;
    }
    .scenario-text ul {
      list-style: none;
      margin-top: 16px;
    }
    .scenario-text li {
      margin-bottom: 10px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .scenario-text li i {
      color: var(--accent);
    }
    @media (max-width: 768px) {
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
      }
    }

    /* 案例滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 16px 0 32px;
      scroll-snap-type: x mandatory;
    }
    .case-card {
      min-width: 280px;
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
      border: 1px solid var(--ice);
    }
    .case-quote {
      font-style: italic;
      margin: 16px 0;
    }
    .case-stat {
      font-size: 2rem;
      font-weight: 700;
      color: var(--glacier);
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pricing-card {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid var(--ice);
      text-align: center;
    }
    .pricing-card.featured {
      background: var(--primary);
      color: white;
      transform: scale(1.03);
      border: none;
    }
    .badge {
      background: var(--accent);
      color: white;
      padding: 4px 16px;
      border-radius: var(--radius-full);
      font-size: 0.8rem;
      font-weight: 700;
      display: inline-block;
      margin-bottom: 12px;
    }
    .price {
      font-size: 2.8rem;
      font-weight: 900;
      margin: 20px 0;
    }
    @media (max-width: 1024px) {
      .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto;
      }
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--ice);
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 150px;
      margin-top: 12px;
    }

    /* CTA 横幅 */
    .cta-band {
      background: var(--primary);
      text-align: center;
      color: white;
      padding: 80px 0;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }