/* roulang page: index */
:root {
      --primary: #E8451E;
      --primary-dark: #C93D18;
      --secondary: #1A2639;
      --accent-white: #F8F9FA;
      --bg-light: #F0F2F5;
      --success: #2D9F4A;
      --warning: #F5B041;
      --text-dark: #1E1E1E;
      --text-muted: #6B7280;
      --white: #FFFFFF;
      --border-light: #E5E7EB;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.06);
      --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.12);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
      --transition: 0.25s ease;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--accent-white);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: var(--white);
      border-bottom: 1px solid var(--border-light);
      z-index: 100;
      transition: box-shadow var(--transition);
    }

    .site-header.scrolled {
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 20px;
      color: var(--text-dark);
    }

    .logo-icon {
      font-size: 28px;
      color: var(--primary);
      line-height: 1;
    }

    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }

    .nav-menu a {
      font-weight: 500;
      color: var(--text-dark);
      transition: color var(--transition);
      font-size: 15px;
    }

    .nav-menu a:hover {
      color: var(--primary);
    }

    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 8px 18px;
      border-radius: 20px;
      font-weight: 600;
    }

    .nav-cta:hover {
      background: var(--primary-dark);
      color: white !important;
    }

    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      border-top: 1px solid var(--border-light);
      padding: 8px 16px;
      justify-content: space-around;
      z-index: 100;
      box-shadow: 0 -2px 8px rgba(0,0,0,0.04);
    }

    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 12px;
      color: var(--text-muted);
    }

    .mobile-nav-item i {
      font-size: 20px;
      margin-bottom: 2px;
    }

    .mobile-nav-cta {
      background: var(--primary);
      color: white;
      border-radius: 24px;
      padding: 10px 18px;
      font-weight: 600;
      font-size: 14px;
      margin-top: -12px;
    }

    /* Hero */
    .hero {
      background: var(--secondary);
      position: relative;
      overflow: hidden;
      padding: 140px 0 100px;
      margin-top: 64px;
    }

    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 600" opacity="0.08"><path d="M0 400 L1200 100 L1200 600 L0 600 Z" fill="white"/><path d="M0 300 L800 50 L800 300 Z" fill="white" opacity="0.3"/></svg>');
      background-size: cover;
      pointer-events: none;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
      position: relative;
    }

    .hero-content h1 {
      font-size: 52px;
      font-weight: 800;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: white;
      margin-bottom: 20px;
    }

    .hero-content p {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      border: none;
      cursor: pointer;
      transition: background var(--transition);
      display: inline-block;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
    }

    .btn-outline {
      border: 2px solid var(--primary);
      color: white;
      padding: 12px 30px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      background: transparent;
      transition: all var(--transition);
    }

    .btn-outline:hover {
      background: var(--primary);
      border-color: var(--primary);
    }

    .hero-image {
      background: rgba(255,255,255,0.1);
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    }

    /* 板块通用 */
    .section {
      padding: 80px 0;
    }

    .section-title {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--text-dark);
    }

    .section-sub {
      color: var(--text-muted);
      margin-bottom: 48px;
      font-size: 18px;
    }

    .bg-light {
      background: var(--bg-light);
    }

    /* 优势卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
    }

    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }

    .feature-icon {
      font-size: 36px;
      color: var(--primary);
      margin-bottom: 16px;
    }

    /* 功能卡片网格 (错落2+1) */
    .func-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }

    .func-card {
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      overflow: hidden;
      transition: var(--transition);
    }

    .func-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }

    .func-card img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      transition: transform 0.3s;
    }

    .func-card:hover img {
      transform: scale(1.03);
    }

    .func-card-content {
      padding: 24px;
    }

    .func-card.wide {
      grid-column: span 2;
      display: grid;
      grid-template-columns: 1fr 1fr;
    }

    .func-card.wide img {
      height: 100%;
    }

    /* 流程 */
    .steps {
      display: flex;
      justify-content: space-between;
      text-align: center;
      position: relative;
    }

    .step {
      flex: 1;
      padding: 0 16px;
    }

    .step-circle {
      width: 80px;
      height: 80px;
      background: rgba(232,69,30,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 20px;
      font-size: 40px;
      font-weight: 800;
      color: var(--primary);
      font-family: var(--font-number);
    }

    /* 数据区 */
    .stats {
      background: var(--secondary);
      color: white;
      padding: 70px 0;
    }

    .stats-grid {
      display: flex;
      justify-content: space-around;
      text-align: center;
    }

    .stat-number {
      font-size: 48px;
      font-weight: 800;
      font-family: var(--font-number);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 700;
      font-size: 18px;
      cursor: pointer;
    }

    .faq-answer {
      padding-top: 12px;
      color: var(--text-muted);
      display: none;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA */
    .cta-band {
      background: var(--primary);
      padding: 80px 0;
      text-align: center;
      color: white;
    }

    .footer {
      background: var(--secondary);
      color: rgba(255,255,255,0.8);
      padding: 40px 0;
      text-align: center;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
    }

    @media (max-width: 768px) {
      .container { padding: 0 16px; }
      .nav-menu { display: none; }
      .mobile-bottom-nav { display: flex; }
      .hero { padding: 120px 0 60px; margin-top: 64px; }
      .hero-content h1 { font-size: 36px; }
      .features-grid { grid-template-columns: 1fr; }
      .func-grid { grid-template-columns: 1fr; }
      .func-card.wide { grid-column: span 1; grid-template-columns: 1fr; }
      .steps { flex-direction: column; gap: 32px; }
      .stats-grid { flex-direction: column; gap: 32px; }
      .section-title { font-size: 28px; }
    }