/* roulang page: index */
:root {
      --primary: #E63916;
      --primary-hover: #C1121F;
      --secondary: #1A1A2E;
      --accent: #00B4D8;
      --success: #2ECC71;
      --bg: #F8F9FA;
      --white: #FFFFFF;
      --gray-100: #F1F3F5;
      --gray-200: #E2E8F0;
      --gray-400: #718096;
      --gray-600: #4A5568;
      --text-dark: #1A1A2E;
      --text-body: #4A5568;
      --text-muted: #718096;
      --border: #E2E8F0;
      --radius-sm: 8px;
      --radius-md: 12px;
      --shadow-nav: 0 1px 3px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 12px 24px rgba(230,57,22,0.08);
      --transition: 0.2s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "Inter", "SF Mono", monospace;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text-body);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, .btn {
      cursor: pointer;
      border: none;
      background: none;
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: var(--white);
      box-shadow: var(--shadow-nav);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 22px;
      color: var(--text-dark);
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="white" stroke-width="2"><polyline points="13 2 3 14 12 14 11 22 21 10 12 10 13 2"/></svg>') center/contain no-repeat;
      background-color: var(--primary);
      display: inline-block;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-dark);
      position: relative;
      padding: 4px 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,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: background var(--transition), transform 0.1s;
      display: inline-block;
      white-space: nowrap;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: scale(1.02);
    }
    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      background: transparent;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: background var(--transition);
    }
    .btn-outline:hover {
      background: rgba(230,57,22,0.1);
    }
    .btn-ghost {
      border: 2px solid white;
      color: white;
      background: transparent;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: background var(--transition);
    }
    .btn-ghost:hover {
      background: rgba(255,255,255,0.1);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--text-dark);
      border-radius: 2px;
      transition: 0.3s;
    }
    /* 移动端导航 */
    .mobile-menu {
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: white;
      box-shadow: 0 4px 12px rgba(0,0,0,0.05);
      transform: translateY(-120%);
      transition: transform 0.3s ease;
      z-index: 999;
      padding: 24px;
    }
    .mobile-menu.active {
      transform: translateY(0);
    }
    .mobile-menu a {
      display: block;
      padding: 16px 0;
      font-weight: 500;
      border-bottom: 1px solid var(--gray-100);
      color: var(--text-dark);
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: linear-gradient(135deg, var(--secondary) 0%, #2D2D44 100%);
      position: relative;
      overflow: hidden;
      min-height: 90vh;
      display: flex;
      align-items: center;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><path d="M20 80 L380 20" stroke="rgba(255,255,255,0.05)" stroke-width="2"/><path d="M30 180 L370 140" stroke="rgba(255,255,255,0.04)" stroke-width="2"/><circle cx="60" cy="300" r="6" fill="rgba(230,57,22,0.15)"/></svg>') repeat;
      pointer-events: none;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1;
      color: white;
    }
    .hero-text h1 {
      font-size: clamp(32px, 5vw, 48px);
      line-height: 1.2;
      font-weight: 800;
      margin-bottom: 20px;
      color: white;
    }
    .hero-sub {
      font-size: 20px;
      color: rgba(255,255,255,0.85);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      background: rgba(255,255,255,0.05);
      border-radius: 20px;
      overflow: hidden;
      border: 1px solid rgba(255,255,255,0.1);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: 32px;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 12px;
    }
    .section-title p {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto;
    }
    /* 功能卡片矩阵 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 32px;
      transition: transform 0.2s, box-shadow 0.2s, border-color 0.2s;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
      border-color: var(--primary);
    }
    .feature-icon {
      font-size: 40px;
      color: var(--primary);
    }
    .feature-content h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 8px;
    }
    .feature-desc {
      color: var(--text-body);
      margin-bottom: 16px;
    }
    .feature-list {
      list-style: none;
    }
    .feature-list li {
      display: flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 8px;
      color: var(--text-body);
      font-size: 15px;
    }
    .feature-list li::before {
      content: '✓';
      color: var(--success);
      font-weight: bold;
    }
    /* 场景板块 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: 0 8px 20px rgba(0,0,0,0.04);
    }
    .scenario-img img {
      width: 100%;
      height: 320px;
      object-fit: cover;
    }
    .scenario-text {
      flex: 1;
    }
    .scenario-text h3 {
      font-size: 26px;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 16px;
    }
    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--white);
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 28px;
    }
    .case-stat {
      font-size: 36px;
      font-weight: 700;
      color: var(--success);
      margin-bottom: 8px;
    }
    .case-logo {
      width: 60px;
      height: 60px;
      background: var(--gray-100);
      border-radius: 12px;
      margin: 16px 0;
    }
    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .price-card {
      background: white;
      border: 1px solid var(--border);
      border-radius: var(--radius-md);
      padding: 36px;
      position: relative;
    }
    .price-card.recommended {
      border-color: var(--primary);
      transform: scale(1.02);
    }
    .badge {
      background: var(--success);
      color: white;
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 14px;
      font-weight: 600;
      position: absolute;
      top: -12px;
      right: 20px;
    }
    .price-amount {
      font-size: 40px;
      font-weight: 700;
      color: var(--text-dark);
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
    }
    .faq-question {
      width: 100%;
      text-align: left;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      background: none;
      border: none;
      display: flex;
      justify-content: space-between;
      color: var(--text-dark);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding-left: 12px;
      border-left: 3px solid transparent;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      border-left-color: var(--primary);
    }
    /* CTA band */
    .cta-band {
      background: var(--secondary);
      padding: 80px 0;
      text-align: center;
      color: white;
    }
    /* footer */
    .footer {
      background: var(--secondary);
      color: #CBD5E0;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .features-grid, .cases-grid, .pricing-grid { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
      .hero-content { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .features-grid, .cases-grid, .pricing-grid { grid-template-columns: 1fr; }
      .scenario-row, .scenario-row.reverse { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }