/* roulang page: index */
:root {
      --primary-deep: #1A1A2E;
      --accent-red: #E94560;
      --accent-red-hover: #C23152;
      --secondary-blue: #0F3460;
      --bg-warm: #F5F0EB;
      --card-white: #FFFFFF;
      --text-main: #1A1A2E;
      --text-secondary: #4A4A5A;
      --text-muted: #6B6B7B;
      --border-light: #E5E0DA;
      --shadow-card: 0 4px 20px rgba(26, 26, 46, 0.06);
      --shadow-card-hover: 0 8px 30px rgba(26, 26, 46, 0.12);
      --radius-card: 12px;
      --radius-button: 8px;
      --radius-input: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --transition-base: 0.25s ease;
      --transition-fast: 0.2s ease;
      --max-width: 1200px;
      --nav-height: 68px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-fast);
    }
    
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: var(--transition-fast);
    }
    
    .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(--nav-height);
      background: var(--card-white);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary-deep);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.3px;
    }
    
    .logo i {
      color: var(--accent-red);
      font-size: 24px;
    }
    
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    
    .nav-menu a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 4px 0;
      position: relative;
      border-bottom: 2px solid transparent;
    }
    
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--accent-red);
      border-bottom-color: var(--accent-red);
    }
    
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      padding: 8px;
    }
    
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary-deep);
      border-radius: 2px;
      transition: var(--transition-fast);
    }
    
    .mobile-panel {
      display: none;
      position: fixed;
      top: var(--nav-height);
      left: 0;
      width: 100%;
      background: var(--card-white);
      flex-direction: column;
      padding: 24px;
      gap: 24px;
      box-shadow: var(--shadow-card);
      z-index: 999;
    }
    
    .mobile-panel a {
      font-size: 18px;
      font-weight: 500;
      color: var(--primary-deep);
    }
    
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    
    .hero-content {
      flex: 1 1 55%;
    }
    
    .hero-visual {
      flex: 1 1 40%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 24px;
      min-height: 360px;
      box-shadow: var(--shadow-card);
      position: relative;
      overflow: hidden;
    }
    
    .hero-visual::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,26,46,0.25) 0%, rgba(15,52,96,0.2) 100%);
    }
    
    h1 {
      font-size: clamp(36px, 5vw, 48px);
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: var(--primary-deep);
      margin-bottom: 20px;
    }
    
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      max-width: 540px;
      margin-bottom: 32px;
      line-height: 1.7;
    }
    
    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    
    .btn-primary {
      background: var(--accent-red);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 16px;
      box-shadow: 0 6px 16px rgba(233, 69, 96, 0.25);
    }
    
    .btn-primary:hover {
      background: var(--accent-red-hover);
      transform: translateY(-1px);
    }
    
    .btn-outline {
      border: 1.5px solid var(--secondary-blue);
      color: var(--secondary-blue);
      padding: 14px 36px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 16px;
      background: transparent;
    }
    
    .btn-outline:hover {
      background: rgba(15, 52, 96, 0.08);
    }
    
    /* 通用板块 */
    section {
      padding: 90px 0;
    }
    
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    
    h2 {
      font-size: clamp(28px, 4vw, 36px);
      font-weight: 600;
      line-height: 1.3;
      color: var(--primary-deep);
    }
    
    .section-sub {
      color: var(--text-muted);
      font-size: 16px;
      max-width: 620px;
      margin: 12px auto 0;
    }
    
    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    
    .feature-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-base);
    }
    
    .feature-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-6px);
    }
    
    .feature-icon {
      font-size: 36px;
      color: var(--accent-red);
      margin-bottom: 20px;
    }
    
    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    
    .feature-card p {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.7;
    }
    
    /* 使用场景 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
      flex-wrap: wrap;
    }
    
    .scene-row.reverse {
      flex-direction: row-reverse;
    }
    
    .scene-img {
      flex: 1 1 45%;
      background-size: cover;
      background-position: center;
      border-radius: 20px;
      min-height: 300px;
      box-shadow: var(--shadow-card);
    }
    
    .scene-text {
      flex: 1 1 45%;
    }
    
    .scene-text h2 {
      margin-bottom: 18px;
      text-align: left;
    }
    
    .scene-text ul {
      list-style: none;
      margin-top: 18px;
    }
    
    .scene-text li {
      display: flex;
      align-items: baseline;
      gap: 10px;
      margin-bottom: 12px;
      font-size: 16px;
      color: var(--text-secondary);
    }
    
    .scene-text li::before {
      content: "●";
      color: var(--accent-red);
      font-size: 12px;
    }
    
    /* 数据背书 */
    .stats-grid {
      display: flex;
      justify-content: center;
      gap: 80px;
      flex-wrap: wrap;
      text-align: center;
    }
    
    .stat-number {
      font-size: 38px;
      font-weight: 700;
      color: var(--accent-red);
      margin-bottom: 8px;
    }
    
    .stat-label {
      font-size: 15px;
      color: var(--text-secondary);
    }
    
    /* FAQ */
    .faq-list {
      max-width: 820px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 14px;
    }
    
    .faq-item {
      background: var(--card-white);
      border-radius: var(--radius-button);
      overflow: hidden;
      box-shadow: 0 2px 10px rgba(0,0,0,0.02);
    }
    
    .faq-question {
      background: var(--bg-warm);
      padding: 16px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      border: none;
      width: 100%;
      text-align: left;
      color: var(--primary-deep);
    }
    
    .faq-icon {
      font-size: 20px;
      transition: var(--transition-fast);
      color: var(--accent-red);
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: white;
    }
    
    .faq-answer p {
      padding: 16px 24px;
      color: var(--text-secondary);
      font-size: 15px;
      line-height: 1.7;
      border-top: 1px solid var(--border-light);
    }
    
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }
    
    .faq-item.open .faq-answer {
      max-height: 200px;
    }
    
    /* 最终CTA */
    .cta-banner {
      background: linear-gradient(135deg, #1A1A2E 0%, #0F3460 100%);
      padding: 80px 0;
      text-align: center;
      color: white;
    }
    
    .cta-banner h2 {
      color: white;
      margin-bottom: 16px;
    }
    
    .cta-banner .btn-primary {
      background: var(--accent-red);
      font-size: 18px;
      padding: 16px 44px;
    }
    
    /* 页脚 */
    .site-footer {
      background: var(--primary-deep);
      color: #B0B0C0;
      padding: 48px 0 28px;
    }
    
    .footer-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 40px;
      margin-bottom: 32px;
    }
    
    .footer-brand p {
      font-size: 14px;
      max-width: 240px;
      margin-top: 12px;
    }
    
    .footer-links {
      display: flex;
      gap: 48px;
    }
    
    .footer-links a {
      font-size: 14px;
      color: #B0B0C0;
      display: block;
      margin-bottom: 10px;
    }
    
    .footer-links a:hover {
      color: var(--accent-red);
    }
    
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      font-size: 13px;
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
    }
    
    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(2, 1fr); }
      .hero { flex-direction: column; }
      .hero-visual { min-height: 280px; width: 100%; }
    }
    
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .mobile-panel.active { display: flex; }
      .features-grid { grid-template-columns: 1fr; }
      .stats-grid { gap: 40px; }
      .scene-row, .scene-row.reverse { flex-direction: column; }
      .footer-grid { flex-direction: column; }
    }