/* roulang page: index */
:root {
      /* 核心色彩系统 */
      --primary-deep: #0A1A0F;
      --accent-neon: #00F0A8;
      --accent-gold: #C9A96E;
      --bg-white: #FAFAFA;
      --card-bg: #FFFFFF;
      --border-light: #E5E5E5;
      --text-dark: #1a1a1a;
      --text-mid: #555;
      --text-soft: #666;
      --text-light: #CCC;
      
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --shadow-card: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(0,240,168,0.12);
      --transition: 0.2s ease;
      --container-max: 1280px;
      --nav-height: 72px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: 'Inter', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      background-color: var(--bg-white);
      color: var(--text-dark);
      line-height: 1.6;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
    }
    
    /* 导航系统 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      z-index: 1000;
      background: transparent;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      display: flex;
      align-items: center;
    }
    
    .site-header.scrolled {
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      border-bottom: 1px solid var(--border-light);
    }
    
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    
    .logo {
      display: flex;
      align-items: center;
      font-weight: 900;
      font-size: 1.8rem;
      letter-spacing: -0.5px;
      color: white;
      transition: color 0.3s;
    }
    
    .scrolled .logo {
      color: var(--primary-deep);
    }
    
    .logo .accent-dot {
      color: var(--accent-neon);
      margin-left: 2px;
    }
    
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    
    .nav-links a {
      font-weight: 500;
      font-size: 1rem;
      color: white;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    
    .scrolled .nav-links a {
      color: #333;
    }
    
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-neon);
      transition: width 0.2s ease;
    }
    
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    
    .nav-links a:hover {
      color: var(--accent-neon);
    }
    
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    
    .hamburger span {
      width: 28px;
      height: 2px;
      background: white;
      transition: 0.2s;
    }
    
    .scrolled .hamburger span {
      background: var(--primary-deep);
    }
    
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--primary-deep);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateX(100%);
      transition: transform 0.35s ease;
      z-index: 999;
    }
    
    .mobile-menu.open {
      transform: translateX(0);
    }
    
    .mobile-menu a {
      font-size: 1.8rem;
      color: white;
      font-weight: 600;
    }
    
    /* 板块通用间距 */
    section {
      padding: 100px 0;
    }
    
    /* Hero 首屏 */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: linear-gradient(180deg, rgba(10,26,15,0.7) 0%, rgba(10,26,15,0.2) 70%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      color: white;
      position: relative;
    }
    
    .hero-content {
      max-width: 700px;
    }
    
    .hero h1 {
      font-size: 48px;
      font-weight: 900;
      line-height: 1.2;
      margin-bottom: 24px;
      letter-spacing: -1px;
    }
    
    .hero .subtitle {
      font-size: 20px;
      color: #CCC;
      margin-bottom: 40px;
      font-weight: 400;
    }
    
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    .btn-primary {
      background: var(--accent-neon);
      color: var(--primary-deep);
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      border: none;
      font-size: 1rem;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
      text-align: center;
    }
    
    .btn-primary:hover {
      background: #00D896;
      transform: scale(1.02);
    }
    
    .btn-outline {
      background: transparent;
      border: 1px solid white;
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: 0.2s;
      display: inline-block;
    }
    
    .btn-outline:hover {
      background: white;
      color: var(--primary-deep);
    }
    
    /* 功能卡片网格 2x3 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    
    .feature-card {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 40px 32px;
      text-align: center;
      box-shadow: var(--shadow-card);
      transition: transform 0.25s, box-shadow 0.25s;
    }
    
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    
    .feature-icon {
      font-size: 38px;
      color: var(--accent-neon);
      margin-bottom: 20px;
    }
    
    .feature-card h3 {
      font-size: 24px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    
    .feature-card p {
      color: var(--text-mid);
      font-size: 1rem;
    }
    
    /* 场景交替图文 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    
    .scenario-text {
      flex: 1;
    }
    
    .scenario-text h2 {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 20px;
    }
    
    .scenario-image {
      flex: 1;
      border-radius: var(--radius-lg);
      overflow: hidden;
    }
    
    .scenario-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    
    .tag {
      display: inline-block;
      background: rgba(0,240,168,0.1);
      color: var(--primary-deep);
      padding: 6px 18px;
      border-radius: 20px;
      font-size: 0.9rem;
      font-weight: 600;
      margin-top: 12px;
    }
    
    /* 案例卡片 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 20px;
      scroll-snap-type: x mandatory;
    }
    
    .case-card {
      flex: 0 0 300px;
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-card);
      scroll-snap-align: start;
    }
    
    .case-stat {
      font-size: 42px;
      font-weight: 900;
      color: var(--accent-neon);
    }
    
    /* FAQ */
    .faq-list {
      max-width: 720px;
      margin: 0 auto;
    }
    
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    
    .faq-question {
      font-weight: 600;
      font-size: 1.2rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-mid);
    }
    
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    
    /* CTA 深色区块 */
    .cta-section {
      background: var(--primary-deep);
      text-align: center;
      color: white;
    }
    
    .cta-section h2 {
      font-size: 36px;
      font-weight: 700;
    }
    
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0 30px;
    }
    
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      text-align: center;
      color: #999;
    }
    
    @media (max-width: 1024px) {
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 32px; }
      .features-grid { grid-template-columns: 1fr; }
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }