/* roulang page: index */
/* 全局设计变量与重置 */
    :root {
      --primary: #FF4D00;
      --primary-hover: #E64400;
      --primary-soft: rgba(255, 77, 0, 0.08);
      --accent-blue: #00C2FF;
      --bg-deep: #0B0E14;
      --bg-card: #161B22;
      --bg-input: #1F2630;
      --border-color: #2A2F3A;
      --text-primary: #E8ECF1;
      --text-secondary: #8A929E;
      --text-white: #FFFFFF;
      --success: #00B578;
      --warning: #FF9F0A;
      --error: #FA5151;
      --shadow-card: 0 10px 28px rgba(0, 0, 0, 0.6);
      --shadow-hover: 0 16px 36px rgba(0, 0, 0, 0.8);
      --radius-lg: 18px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --transition: 0.2s ease-in-out;
      --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --container-padding: 32px;
      --max-width: 1280px;
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-deep);
    }

    body {
      font-family: var(--font-sans);
      background: var(--bg-deep);
      color: var(--text-primary);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      transition: all var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 var(--container-padding);
    }

    /* 按钮系统 */
    .btn-primary {
      background: var(--primary);
      color: var(--text-white);
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
      box-shadow: 0 4px 12px rgba(255, 77, 0, 0.35);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: 0 8px 20px rgba(255, 77, 0, 0.5);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      font-weight: 600;
      font-size: 16px;
    }
    .btn-outline:hover {
      background: rgba(255, 77, 0, 0.1);
      border-color: var(--primary-hover);
      color: #ff6b2b;
    }
    .btn-lg {
      padding: 14px 36px;
      font-size: 18px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(11, 14, 20, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 1000;
      border-bottom: 1px solid rgba(42, 47, 58, 0.6);
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 24px;
      font-weight: 700;
      color: var(--text-white);
      letter-spacing: -0.5px;
    }
    .logo-icon {
      font-size: 28px;
      color: var(--primary);
      transform: rotate(-10deg);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 6px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .menu-toggle span {
      width: 26px;
      height: 2px;
      background: var(--text-primary);
      transition: var(--transition);
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: rgba(11, 14, 20, 0.96);
      backdrop-filter: blur(16px);
      padding: 24px 0;
      flex-direction: column;
      gap: 16px;
      border-bottom: 1px solid var(--border-color);
    }
    .mobile-menu a {
      display: block;
      padding: 12px 32px;
      font-size: 18px;
      color: var(--text-primary);
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
      position: relative;
    }
    .section-title {
      font-size: 40px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 16px;
      color: var(--text-white);
    }
    .section-subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      max-width: 700px;
      margin: 0 auto 48px;
    }
    .text-center {
      text-align: center;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background: radial-gradient(circle at 30% 40%, rgba(255,77,0,0.08) 0%, transparent 60%), var(--bg-deep);
      overflow: hidden;
    }
    .hero-bg {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.18;
      z-index: 0;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }
    .hero h1 {
      font-size: 58px;
      font-weight: 800;
      line-height: 1.15;
      margin-bottom: 20px;
      color: var(--text-white);
    }
    .hero h1 span {
      color: var(--primary);
      position: relative;
    }
    .hero p {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 36px;
      max-width: 560px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .scroll-hint {
      position: absolute;
      bottom: 30px;
      right: 40px;
      color: var(--text-secondary);
      font-size: 14px;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 6px;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      transition: all var(--transition);
      box-shadow: var(--shadow-card);
    }
    .feature-card:hover {
      border-color: var(--primary);
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 32px;
      color: var(--accent-blue);
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 22px;
      margin-bottom: 12px;
      color: var(--text-white);
    }
    .feature-card p {
      color: var(--text-secondary);
      font-size: 15px;
    }

    .scenario-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .scenario-text {
      flex: 1;
    }
    .scenario-text h3 {
      font-size: 28px;
      margin-bottom: 16px;
    }
    .case-card {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      padding: 28px;
      text-align: center;
      border: 1px solid var(--border-color);
    }
    .case-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--primary);
      display: block;
    }

    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pricing-card {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-lg);
      padding: 36px 24px;
      text-align: center;
      transition: all var(--transition);
    }
    .pricing-card.featured {
      border-color: var(--primary);
      box-shadow: 0 0 0 2px rgba(255,77,0,0.3);
      transform: scale(1.02);
    }
    .price {
      font-size: 42px;
      font-weight: 700;
      color: var(--text-white);
      margin: 16px 0;
    }

    .faq-item {
      background: var(--bg-card);
      border: 1px solid var(--border-color);
      border-radius: var(--radius-md);
      margin-bottom: 14px;
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: transparent;
      color: var(--text-primary);
      font-size: 17px;
      font-weight: 600;
      border: none;
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: var(--text-secondary);
      display: none;
    }
    .faq-item.open .faq-answer {
      display: block;
    }

    .cta-banner {
      background: linear-gradient(135deg, #FF4D00 0%, #B83500 100%);
      border-radius: var(--radius-lg);
      padding: 64px 40px;
      text-align: center;
      margin: 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0 30px;
      border-top: 1px solid var(--border-color);
    }

    @media (max-width: 1024px) {
      .grid-3, .pricing-grid { grid-template-columns: repeat(2, 1fr); }
      .scenario-row { flex-direction: column; }
      .hero h1 { font-size: 44px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: flex; }
      .mobile-menu.active { display: flex; }
      .grid-3, .pricing-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 36px; }
    }