/* roulang page: index */
/* 全局设计变量与重置 */
    :root {
      --primary: #E8453C;
      --primary-dark: #c5302c;
      --secondary: #C9A96E;
      --secondary-light: #e0c78a;
      --accent: #00E5A0;
      --bg-light: #F7F5F2;
      --bg-dark: #1A1A1E;
      --text-dark: #2C2C2C;
      --text-light: #ffffff;
      --text-muted: #6b6b6b;
      --border-subtle: rgba(0,0,0,0.04);
      --border-light: rgba(255,255,255,0.08);
      --radius-card-lg: 20px;
      --radius-card: 14px;
      --radius-sm: 8px;
      --radius-btn: 50px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 12px 32px rgba(232,69,60,0.12);
      --transition: 0.25s ease;
      --font-cn: 'PingFang SC', 'Microsoft YaHei', 'Heiti SC', sans-serif;
      --font-en: 'Inter', 'SF Pro Display', sans-serif;
      --max-width: 1280px;
      --header-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-cn);
      background-color: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.7;
      letter-spacing: 0.3px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      font-weight: 600;
    }
    /* 容器系统 */
    .container {
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(26,26,30,0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid transparent;
      background-image: linear-gradient(rgba(26,26,30,0.85), rgba(26,26,30,0.85)), linear-gradient(90deg, var(--primary), var(--secondary));
      background-origin: border-box;
      background-clip: padding-box, border-box;
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-family: var(--font-cn);
      font-weight: 700;
      font-size: 1.5rem;
      background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      background: none;
      -webkit-text-fill-color: var(--primary);
      font-size: 1.8rem;
      background: var(--primary);
      -webkit-background-clip: text;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
      list-style: none;
      color: white;
      font-weight: 500;
    }
    .nav-links a {
      color: white;
      position: relative;
      padding: 0.25rem 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.3s;
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .mega-menu-trigger {
      position: relative;
    }
    .mega-panel {
      position: absolute;
      top: 100%;
      right: 0;
      width: 320px;
      background: rgba(26,26,30,0.95);
      backdrop-filter: blur(16px);
      border-radius: 16px;
      padding: 1.2rem;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      opacity: 0;
      visibility: hidden;
      transform: translateY(10px);
      transition: 0.3s ease;
      border: 1px solid var(--border-light);
      z-index: 99;
    }
    .mega-menu-trigger:hover .mega-panel {
      opacity: 1;
      visibility: visible;
      transform: translateY(0);
    }
    .mega-card {
      background: rgba(255,255,255,0.05);
      border-radius: 8px;
      padding: 0.8rem;
      color: white;
      font-size: 0.9rem;
      display: flex;
      flex-direction: column;
      gap: 4px;
    }
    .mega-card i {
      color: var(--primary);
    }
    .menu-toggle {
      display: none;
      font-size: 1.8rem;
      color: white;
    }
    /* Hero */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: var(--bg-dark);
      position: relative;
      display: flex;
      align-items: center;
      overflow: hidden;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: repeating-linear-gradient(45deg, rgba(232,69,60,0.08) 0px, rgba(232,69,60,0.08) 2px, transparent 2px, transparent 12px);
      pointer-events: none;
    }
    .hero-bg-img {
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.25;
      mask-image: linear-gradient(to left, black, transparent);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 650px;
    }
    .hero h1 {
      font-size: clamp(2.8rem, 5vw, 3.8rem);
      font-weight: 800;
      letter-spacing: -0.5px;
      color: white;
      line-height: 1.2;
      margin-bottom: 1rem;
    }
    .hero .subtitle {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 2rem;
    }
    .hero-actions {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      border-radius: var(--radius-btn);
      padding: 0.9rem 2.2rem;
      font-weight: 700;
      box-shadow: 0 8px 18px rgba(232,69,60,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 0.9rem 2.2rem;
    }
    .btn-outline:hover {
      background: rgba(232,69,60,0.1);
    }
    /* 板块通用 */
    .section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      margin-bottom: 0.75rem;
      color: var(--text-dark);
    }
    .section-sub {
      color: var(--text-muted);
      margin-bottom: 3rem;
    }
    /* 服务非对称栅格 */
    .services-grid {
      display: grid;
      grid-template-columns: 2fr 1fr;
      gap: 24px;
    }
    .service-card-large {
      grid-row: span 2;
      background: white;
      border-radius: var(--radius-card-lg);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 1.8rem;
      box-shadow: var(--shadow-card);
      display: flex;
      flex-direction: column;
    }
    .service-icon {
      width: 50px;
      height: 50px;
      background: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 1.4rem;
      margin-bottom: 1rem;
    }
    /* 数据带 */
    .stats-band {
      background: var(--bg-dark);
      padding: 70px 0;
    }
    .stats-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 2rem;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-en);
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent);
    }
    .stat-label {
      color: rgba(255,255,255,0.75);
    }
    /* 案例左右交替 */
    .case-row {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 4rem;
    }
    .case-row.reverse {
      flex-direction: row-reverse;
    }
    .case-img {
      flex: 1;
      border-radius: 16px;
      overflow: hidden;
      border: 1px solid var(--border-subtle);
    }
    .case-text {
      flex: 1;
    }
    /* 解决方案大卡 */
    .solution-card {
      background: white;
      border-radius: var(--radius-card-lg);
      display: flex;
      margin-bottom: 2rem;
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .solution-card.reverse {
      flex-direction: row-reverse;
    }
    .solution-img {
      flex: 1;
      min-height: 280px;
    }
    .solution-content {
      flex: 1;
      padding: 2.5rem;
    }
    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 1rem;
      overflow: hidden;
    }
    .faq-question {
      padding: 1.2rem 1.8rem;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding: 0 1.8rem;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.5rem;
    }
    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #C9A96E 0%, #b8934b 100%);
      padding: 80px 0;
      text-align: center;
      color: var(--text-dark);
    }
    .btn-gold {
      background: white;
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 1rem 2.5rem;
      font-weight: 700;
    }
    /* 页脚 */
    .footer {
      background: var(--bg-dark);
      color: #ccc;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    @media (max-width: 1024px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .services-grid { grid-template-columns: 1fr; }
      .case-row, .case-row.reverse { flex-direction: column; }
      .solution-card, .solution-card.reverse { flex-direction: column; }
      .stats-grid { justify-content: center; }
      .hero h1 { font-size: 2.2rem; }
    }