/* roulang page: index */
:root {
      --primary: #E43D2A;
      --primary-dark: #C0331F;
      --primary-soft: rgba(228, 61, 42, 0.08);
      --secondary: #1A1A2E;
      --accent: #F5A623;
      --accent-light: rgba(245, 166, 35, 0.15);
      --bg: #F9FAFB;
      --surface: #FFFFFF;
      --text-primary: #1F2937;
      --text-secondary: #4B5563;
      --text-muted: #6B7280;
      --border: #E5E7EB;
      --border-light: #F3F4F6;
      --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04);
      --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 12px 28px rgba(228, 61, 42, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-pill: 50px;
      --radius-tag: 6px;
      --transition: all 0.3s ease;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', system-ui, -apple-system, sans-serif;
      --font-mono: 'Inter', 'SF Mono', monospace;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    h1, h2, h3 {
      font-weight: 700;
    }

    h2 {
      font-size: 2rem;
      letter-spacing: -0.3px;
      margin-bottom: 1rem;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

    img {
      max-width: 100%;
      display: block;
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }

    /* 导航系统 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      z-index: 999;
      transition: var(--transition);
      backdrop-filter: blur(0px);
      background-color: transparent;
    }

    .header.scrolled {
      background-color: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(24px);
      box-shadow: var(--shadow-sm);
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      font-weight: 800;
      font-size: 1.75rem;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 0.4rem;
      letter-spacing: -0.5px;
    }

    .logo i {
      font-size: 2rem;
      color: var(--accent);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2.2rem;
    }

    .nav-link {
      font-weight: 500;
      color: var(--text-primary);
      position: relative;
      padding: 0.25rem 0;
      transition: color 0.2s;
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2.5px;
      background: var(--primary);
      transition: width 0.25s ease;
      border-radius: 2px;
    }

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

    .nav-link:hover::after {
      width: 100%;
    }

    .btn-capsule {
      background: var(--primary);
      color: white;
      padding: 0.6rem 1.5rem;
      border-radius: var(--radius-pill);
      font-weight: 600;
      font-size: 0.95rem;
      transition: var(--transition);
      border: none;
      white-space: nowrap;
    }

    .btn-capsule:hover {
      background: var(--primary-dark);
      transform: scale(1.02);
    }

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

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--text-primary);
      border-radius: 4px;
      transition: 0.3s;
    }

    .mobile-drawer {
      position: fixed;
      top: 0;
      right: 0;
      width: 280px;
      height: 100vh;
      background: var(--secondary);
      transform: translateX(100%);
      transition: 0.35s ease;
      z-index: 1000;
      padding: 2rem 1.8rem;
      display: flex;
      flex-direction: column;
      gap: 2.2rem;
    }

    .mobile-drawer.active {
      transform: translateX(0);
    }

    .mobile-drawer a {
      color: white;
      font-size: 1.2rem;
      font-weight: 500;
      border-bottom: 1px solid rgba(255,255,255,0.2);
      padding-bottom: 0.5rem;
    }

    .drawer-close {
      align-self: flex-end;
      background: none;
      border: none;
      color: white;
      font-size: 1.6rem;
    }

    /* 区块通用 */
    section {
      padding: 100px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    /* Hero */
    .hero {
      padding-top: 130px;
      background: linear-gradient(135deg, #fff 0%, #F9FAFB 100%);
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }

    .hero-content {
      flex: 1 1 50%;
    }

    .hero-content h1 {
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }

    .hero-highlight {
      color: var(--primary);
    }

    .hero-desc {
      font-size: 1.15rem;
      color: var(--text-secondary);
      margin-bottom: 2rem;
      max-width: 500px;
    }

    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 0.85rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      transition: var(--transition);
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
    }

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

    .hero-visual {
      flex: 1 1 50%;
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: var(--shadow-hover);
    }

    .hero-visual img {
      width: 100%;
      height: auto;
      object-fit: cover;
      border-radius: 24px;
    }

    /* 卡片共通 */
    .card {
      background: var(--surface);
      border-radius: var(--radius-card);
      border: 1px solid var(--border);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }

    .card:hover {
      transform: translateY(-6px);
      box-shadow: 0 16px 32px rgba(228, 61, 42, 0.08);
      border-color: var(--primary);
    }

    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      margin-top: 2.5rem;
    }

    .feature-item {
      text-align: left;
      padding: 1.8rem 1.2rem;
      border-radius: 16px;
      background: white;
      transition: var(--transition);
      border: 1px solid var(--border-light);
    }

    .feature-icon {
      font-size: 2.2rem;
      color: var(--primary);
      margin-bottom: 1rem;
      background: var(--primary-soft);
      width: 52px;
      height: 52px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: var(--radius-btn);
    }

    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2rem;
    }

    .service-card img {
      border-radius: var(--radius-card) var(--radius-card) 0 0;
      height: 200px;
      object-fit: cover;
      width: 100%;
    }

    .badge {
      background: var(--accent);
      color: #1F2937;
      font-weight: 700;
      font-size: 0.7rem;
      padding: 0.2rem 0.8rem;
      border-radius: var(--radius-tag);
      display: inline-block;
      letter-spacing: 0.3px;
    }

    .stats-row {
      display: flex;
      justify-content: space-around;
      text-align: center;
      background: white;
      padding: 3rem 1rem;
      border-radius: 28px;
      flex-wrap: wrap;
      gap: 2rem;
      margin-top: 1.5rem;
    }

    .stat-number {
      font-size: 2.7rem;
      font-weight: 800;
      color: var(--accent);
      font-family: var(--font-mono);
    }

    .process-steps {
      display: flex;
      justify-content: space-between;
      margin-top: 2rem;
      flex-wrap: wrap;
      gap: 1.5rem;
    }

    .step {
      flex: 1;
      text-align: center;
      padding: 1.5rem;
    }

    .step-circle {
      background: var(--primary);
      color: white;
      width: 48px;
      height: 48px;
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.4rem;
      margin-bottom: 1rem;
    }

    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2rem;
    }

    .faq-item {
      border-bottom: 1px solid var(--border);
      background: white;
      padding: 1.2rem 1rem;
      border-radius: 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: var(--text-secondary);
    }

    .faq-item.active .faq-answer {
      max-height: 180px;
      padding-top: 1rem;
    }

    .cta-section {
      background: var(--secondary);
      color: white;
      text-align: center;
      border-radius: 32px;
      margin: 3rem 0;
    }

    .footer {
      background: #0F0F1A;
      color: #E5E7EB;
      padding: 3rem 0 1.5rem;
    }

    @media (max-width: 1024px) {
      .hero-grid { flex-direction: column; }
      .features-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid, .cases-grid { grid-template-columns: repeat(2, 1fr); }
      .process-steps { flex-direction: column; }
    }

    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .features-grid, .services-grid, .cases-grid { grid-template-columns: 1fr; }
    }