/* roulang page: index */
:root {
      --primary: #E33B1C;
      --primary-dark: #C42F14;
      --secondary-dark: #1A1A2E;
      --bg-warm: #F5F0E8;
      --accent: #00B4A6;
      --accent-dark: #009B8F;
      --text-main: #2C2C2C;
      --text-muted: #5A5A5A;
      --text-light: #B0B0B0;
      --border: #E0DCD5;
      --white: #FFFFFF;
      --shadow-sm: 0 2px 12px rgba(26,26,46,0.06);
      --shadow-md: 0 8px 28px rgba(26,26,46,0.12);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --transition: 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      padding: 0;
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4, h5, h6 {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      font-weight: 600;
      margin-top: 0;
    }

    a {
      color: var(--accent);
      text-decoration: none;
      transition: color var(--transition);
    }
    a:hover {
      color: var(--accent-dark);
      text-decoration: underline;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding-left: 5vw;
      padding-right: 5vw;
    }

    @media (max-width: 768px) {
      .container {
        padding-left: 20px;
        padding-right: 20px;
      }
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: var(--secondary-dark);
      border-bottom: 2px solid var(--primary);
      z-index: 100;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 5vw;
      transition: background 0.3s;
    }
    .logo-area {
      display: flex;
      align-items: baseline;
      gap: 0.5rem;
    }
    .logo-text {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
      line-height: 1;
    }
    .logo-domain {
      font-size: 12px;
      color: #888;
      margin-left: 2px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      color: #ddd;
      font-size: 15px;
      font-weight: 500;
      position: relative;
      text-decoration: none;
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--primary);
      text-decoration: none;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    .mega-trigger {
      position: relative;
      cursor: pointer;
      color: #ddd;
      font-size: 15px;
      font-weight: 500;
      padding: 8px 0;
    }
    .mega-trigger:hover {
      color: var(--primary);
    }
    .mega-panel {
      position: absolute;
      top: 60px;
      right: 0;
      width: 640px;
      background: var(--white);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-md);
      padding: 28px 24px;
      display: flex;
      gap: 32px;
      opacity: 0;
      visibility: hidden;
      transform: translateY(8px);
      transition: all 0.2s ease;
      z-index: 120;
      border: 1px solid var(--border);
    }
    .mega-trigger:hover .mega-panel {
      opacity: 1;
      visibility: visible;
      transform: translateY(0);
    }
    .mega-col {
      flex: 1;
    }
    .mega-col h4 {
      font-size: 16px;
      font-weight: 700;
      margin-bottom: 14px;
      color: var(--secondary-dark);
    }
    .mega-col a {
      display: block;
      padding: 6px 0;
      color: var(--text-main);
      font-size: 15px;
      text-decoration: none;
    }
    .mega-col a:hover {
      color: var(--primary);
      text-decoration: underline;
    }
    .mega-img {
      width: 100%;
      height: 60px;
      background: #eee;
      border-radius: 8px;
      margin-bottom: 10px;
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 26px;
      cursor: pointer;
    }

    @media (max-width: 1024px) {
      .nav-links {
        gap: 16px;
      }
      .mega-panel {
        width: 480px;
      }
    }
    @media (max-width: 768px) {
      .nav-links, .mega-trigger {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .site-header {
        padding: 0 20px;
      }
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--secondary-dark);
      flex-direction: column;
      padding: 20px;
      z-index: 99;
    }
    .mobile-menu a {
      color: white;
      padding: 12px 0;
      border-bottom: 1px solid rgba(255,255,255,0.1);
      font-size: 16px;
      text-decoration: none;
    }
    .mobile-menu.active {
      display: flex;
    }

    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: 36px;
      font-weight: 700;
      color: var(--secondary-dark);
      margin-bottom: 12px;
      letter-spacing: 0;
      line-height: 1.35;
    }
    .title-decor {
      width: 48px;
      height: 3px;
      background: var(--primary);
      border-radius: 4px;
      margin: 0 auto;
    }

    .hero {
      min-height: 85vh;
      background: linear-gradient(135deg, #1A1A2E 0%, #2D2D44 100%);
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      margin-top: 72px;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 40px;
      width: 100%;
    }
    .hero-left {
      flex: 1 1 55%;
      color: white;
    }
    .hero-left h1 {
      font-size: 48px;
      font-weight: 700;
      letter-spacing: -0.5px;
      line-height: 1.2;
      color: white;
      margin-bottom: 1rem;
    }
    .hero-sub {
      font-size: 18px;
      color: #C0C0C0;
      margin-bottom: 2rem;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      border: none;
      box-shadow: 0 4px 14px rgba(227,59,28,0.3);
      transition: 0.2s;
      display: inline-block;
      text-decoration: none;
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      color: white;
      text-decoration: none;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      transition: 0.2s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      text-decoration: none;
    }
    .btn-white-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
    }
    .btn-white-outline:hover {
      background: white;
      color: var(--primary);
    }
    .hero-right {
      flex: 1 1 45%;
      text-align: center;
    }
    .hero-right img {
      max-width: 100%;
      height: auto;
      animation: float 6s ease-in-out infinite;
      border-radius: 20px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }
    @keyframes float {
      0% { transform: translateY(0); }
      50% { transform: translateY(-12px); }
      100% { transform: translateY(0); }
    }
    @media (max-width: 768px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
      }
      .hero-left h1 {
        font-size: 32px;
      }
      .hero-right img {
        width: 80%;
      }
      .btn-group {
        justify-content: center;
      }
    }

    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
      align-items: start;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      border: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
      position: relative;
      overflow: hidden;
    }
    .service-card:nth-child(1) { border-radius: var(--radius-md) var(--radius-md) var(--radius-sm) var(--radius-sm); }
    .service-card:nth-child(2) { margin-top: -20px; border-radius: var(--radius-md); }
    .service-card:nth-child(3) { border-radius: var(--radius-sm) var(--radius-sm) var(--radius-md) var(--radius-md); }
    .service-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 8px;
      background: var(--primary);
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
      border-color: var(--primary);
    }
    .service-icon {
      font-size: 48px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
    }
    .stat-grid {
      background: var(--secondary-dark);
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 40px;
      text-align: center;
      padding: 60px 5vw;
      border-radius: var(--radius-lg);
    }
    .stat-item h3 {
      font-size: 42px;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 8px;
    }
    .stat-item p {
      color: #ccc;
      font-size: 16px;
    }

    .solution-row {
      display: flex;
      align-items: center;
      gap: 40px;
      margin-bottom: 80px;
    }
    .solution-text, .solution-img {
      flex: 1;
    }
    .solution-img img {
      width: 100%;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
    }
    .case-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    .case-card {
      border-radius: var(--radius-md);
      overflow: hidden;
      position: relative;
    }
    .case-card img {
      width: 100%;
      display: block;
      transition: transform 0.3s;
    }
    .case-card:hover img {
      transform: scale(1.04);
    }

    .faq-item {
      background: var(--white);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      border: 1px solid var(--border);
    }
    .faq-question {
      padding: 18px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .cta-banner {
      background: var(--primary);
      text-align: center;
      padding: 60px 20px;
      color: white;
    }
    .footer {
      background: var(--secondary-dark);
      color: #B0B0B0;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .services-grid, .stat-grid, .case-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .solution-row {
        flex-direction: column;
      }
    }