/* roulang page: index */
:root {
      --primary-red: #C41E3A;
      --deep-red: #8B1A2B;
      --dark-base: #1A1A1A;
      --gray-bg: #F5F5F5;
      --white: #FFFFFF;
      --text-dark: #333333;
      --text-medium: #555555;
      --text-light: #888888;
      --border-light: #EEEEEE;
      --shadow-card: 0 2px 16px rgba(0,0,0,0.06);
      --shadow-hover: 0 12px 28px rgba(196,30,58,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.25s ease;
      --font-stack: -apple-system, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --container-max: 1200px;
      --nav-height: 72px;
    }

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

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

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

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

    button, input {
      font-family: inherit;
      border: none;
      outline: none;
      cursor: pointer;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 固定导航栏 - 白底平台导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 6px rgba(0,0,0,0.04);
      z-index: 1000;
      display: flex;
      align-items: center;
    }

    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: baseline;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: 0.5px;
      color: var(--dark-base);
    }
    .logo span {
      color: var(--primary-red);
    }
    .logo small {
      font-size: 0.8rem;
      font-weight: 400;
      color: var(--text-light);
      margin-left: 4px;
    }

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

    .nav-links a {
      font-weight: 500;
      color: var(--text-dark);
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: border-color var(--transition), color var(--transition);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary-red);
      border-bottom-color: var(--primary-red);
    }

    .btn-nav {
      background: var(--primary-red);
      color: var(--white) !important;
      padding: 10px 22px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none !important;
      transition: background var(--transition), transform var(--transition);
    }
    .btn-nav:hover {
      background: var(--deep-red);
      transform: translateY(-2px);
    }

    .menu-toggle {
      display: none;
      background: none;
      font-size: 1.8rem;
      color: var(--dark-base);
      padding: 8px;
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: var(--nav-height);
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(16px);
      padding: 24px 0;
      box-shadow: 0 8px 20px rgba(0,0,0,0.08);
      flex-direction: column;
      gap: 24px;
      text-align: center;
      z-index: 999;
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 500;
      display: block;
      padding: 8px;
      color: var(--text-dark);
    }
    .mobile-menu a:hover {
      color: var(--primary-red);
    }

    /* Hero 首屏 */
    .hero {
      background-color: var(--dark-base);
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      min-height: 620px;
      display: flex;
      align-items: center;
      margin-top: var(--nav-height);
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(26,26,26,0.7);
      z-index: 1;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 50%;
    }
    .hero-text h1 {
      font-size: clamp(2.4rem, 5vw, 3.5rem);
      font-weight: 700;
      color: var(--white);
      letter-spacing: -0.5px;
      line-height: 1.3;
      margin-bottom: 20px;
    }
    .hero-text p {
      color: #CCCCCC;
      font-size: 1.1rem;
      max-width: 500px;
      margin-bottom: 36px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary-red);
      color: var(--white);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
      display: inline-block;
      text-align: center;
      box-shadow: 0 4px 12px rgba(196,30,58,0.3);
    }
    .btn-primary:hover {
      background: var(--deep-red);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(139,26,43,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-red);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-outline:hover {
      background: var(--primary-red);
      color: var(--white);
    }
    .hero-image {
      flex: 1 1 40%;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }

    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    .section-title h2 {
      font-size: 2.1rem;
      font-weight: 600;
      color: var(--dark-base);
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--text-light);
      max-width: 600px;
      margin: 0 auto;
    }

    /* 核心优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 32px 20px;
      text-align: center;
      transition: box-shadow var(--transition), transform var(--transition);
    }
    .feature-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--primary-red);
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 1.2rem;
      margin-bottom: 10px;
    }

    /* 服务卡片网格 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: var(--transition);
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--primary-red);
    }
    .service-card img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .service-card-body {
      padding: 24px;
    }
    .service-card h3 {
      font-weight: 600;
      margin-bottom: 8px;
    }

    /* 数据展示区 */
    .stats-band {
      background: var(--dark-base);
      color: var(--white);
      padding: 70px 0;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary-red);
      margin-bottom: 8px;
    }
    .stat-label {
      color: #aaa;
      font-size: 0.95rem;
    }

    /* 流程区 */
    .steps-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    .step-item {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 18px;
      border: 1px solid var(--border-light);
    }
    .step-num {
      width: 40px;
      height: 40px;
      background: var(--primary-red);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 16px;
      font-weight: 700;
    }

    /* 合作品牌区 */
    .brands-wall {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 40px;
      align-items: center;
      opacity: 0.8;
    }

    /* FAQ 手风琴 */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
    }
    .faq-question {
      width: 100%;
      text-align: left;
      background: none;
      font-size: 1.1rem;
      font-weight: 600;
      padding: 20px 16px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-dark);
      border-left: 4px solid var(--primary-red);
      background: var(--white);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: var(--gray-bg);
      padding: 0 16px;
    }
    .faq-answer.active {
      max-height: 200px;
      padding: 16px;
    }

    /* 最终CTA */
    .cta-section {
      background: var(--dark-base);
      text-align: center;
      padding: 80px 0;
    }
    .cta-section h2 {
      color: white;
      font-size: 2rem;
      margin-bottom: 16px;
    }

    /* 页脚 */
    .site-footer {
      background: #111;
      color: #ccc;
      padding: 50px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
    }
    .footer-grid h4 {
      color: white;
      margin-bottom: 16px;
    }
    .footer-grid a {
      color: #aaa;
      display: block;
      margin-bottom: 8px;
    }
    .copyright {
      text-align: center;
      color: #777;
      margin-top: 32px;
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .features-grid, .stats-grid, .steps-grid { grid-template-columns: repeat(2,1fr); }
      .services-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .mobile-menu.active { display: flex; }
      .hero-content { flex-direction: column; }
      .features-grid, .services-grid, .stats-grid, .steps-grid, .footer-grid { grid-template-columns: 1fr; }
      section { padding: 60px 0; }
    }