/* roulang page: index */
:root {
      --color-primary: #C8102E;
      --color-primary-dark: #A50F25;
      --color-dark: #1A1A1A;
      --color-dark-soft: #2D2D2D;
      --color-gold: #FFD700;
      --color-bg: #F5F5F5;
      --color-white: #FFFFFF;
      --color-text: #1A1A1A;
      --color-text-soft: #555555;
      --color-border: #E0E0E0;
      --color-success: #2E7D32;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --shadow-card: 0 2px 8px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 6px 20px rgba(198,16,46,0.15);
      --shadow-button: 0 4px 12px rgba(198,16,46,0.4);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-number: "Inter", "Roboto", sans-serif;
      --max-width: 1200px;
      --nav-height: 64px;
      --section-gap: 80px;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--color-bg);
      color: var(--color-text);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      outline: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all 0.25s ease;
    }

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

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(6px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
      z-index: 1000;
      display: flex;
      align-items: center;
      transition: background 0.3s ease, box-shadow 0.3s ease;
    }

    .header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--color-dark);
      white-space: nowrap;
    }

    .logo-icon {
      width: 36px;
      height: 36px;
      background: linear-gradient(135deg, #C8102E 0%, #1A1A1A 100%);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #FFD700;
      font-weight: bold;
      font-size: 20px;
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-link {
      font-weight: 500;
      color: var(--color-text-soft);
      transition: color 0.2s;
      white-space: nowrap;
    }

    .nav-link:hover,
    .nav-link.active {
      color: var(--color-primary);
    }

    .btn-primary {
      background: var(--color-primary);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 0.95rem;
      box-shadow: 0 4px 10px rgba(198,16,46,0.3);
    }

    .btn-primary:hover {
      background: var(--color-primary-dark);
      box-shadow: var(--shadow-button);
      transform: translateY(-2px);
      color: white;
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--color-primary);
      color: var(--color-primary);
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
    }

    .btn-outline:hover {
      background: var(--color-primary);
      color: white;
      transform: translateY(-2px);
    }

    .btn-gold {
      background: linear-gradient(135deg, #C8102E 0%, #1A1A1A 100%);
      color: var(--color-gold);
      padding: 16px 36px;
      border-radius: var(--radius-sm);
      font-weight: 700;
      font-size: 1.1rem;
      box-shadow: 0 8px 18px rgba(0,0,0,0.3);
    }

    .btn-gold:hover {
      transform: translateY(-3px);
      box-shadow: 0 12px 24px rgba(198,16,46,0.5);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--color-dark);
      transition: 0.3s;
    }

    /* 移动端抽屉 */
    .mobile-drawer {
      position: fixed;
      top: 0;
      right: -100%;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: var(--color-dark);
      z-index: 2000;
      padding: 24px;
      display: flex;
      flex-direction: column;
      gap: 32px;
      transition: right 0.3s ease;
    }

    .mobile-drawer.open {
      right: 0;
    }

    .drawer-close {
      align-self: flex-end;
      background: none;
      border: none;
      color: white;
      font-size: 28px;
    }

    .drawer-menu {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }

    .drawer-link {
      color: white;
      font-size: 1.2rem;
      font-weight: 500;
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #1A1A1A 0%, #2D2D2D 100%);
      color: white;
      padding: 140px 0 100px;
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: "";
      position: absolute;
      top: -50%;
      right: -10%;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle, rgba(200,16,46,0.25) 0%, transparent 70%);
      border-radius: 50%;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
      position: relative;
      z-index: 2;
    }

    .hero-content {
      flex: 1;
    }

    .hero h1 {
      font-size: clamp(2.2rem, 5vw, 3.2rem);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }

    .hero .subtitle {
      font-size: 1.15rem;
      color: #DDDDDD;
      margin-bottom: 32px;
      max-width: 500px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }

    .hero-image img {
      max-height: 380px;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      object-fit: cover;
    }

    /* 板块通用 */
    .section {
      padding: var(--section-gap) 0;
    }

    .section-title {
      font-size: 2rem;
      font-weight: 600;
      text-align: center;
      margin-bottom: 48px;
      color: var(--color-dark);
    }

    /* 优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .feature-card {
      background: var(--color-white);
      border: 1px solid var(--color-border);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      text-align: center;
      transition: all 0.25s;
    }

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

    .feature-icon {
      font-size: 2.5rem;
      margin-bottom: 16px;
    }

    .feature-card h3 {
      font-size: 1.3rem;
      margin-bottom: 8px;
    }

    /* 产品卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .product-card {
      background: white;
      border-radius: var(--radius-md);
      border: 1px solid var(--color-border);
      box-shadow: var(--shadow-card);
      overflow: hidden;
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }

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

    .card-img {
      height: 200px;
      background: #E8E8E8;
      position: relative;
      overflow: hidden;
    }

    .card-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }

    .card-body {
      padding: 20px;
      flex: 1;
    }

    .card-body h3 {
      font-size: 1.25rem;
      margin-bottom: 8px;
    }

    .tags {
      display: flex;
      gap: 8px;
      flex-wrap: wrap;
      margin-top: 12px;
    }

    .tag {
      background: #F0F0F0;
      color: var(--color-primary);
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }

    /* 流程/数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }

    .stat-number {
      font-family: var(--font-number);
      font-size: 3rem;
      font-weight: 700;
      color: var(--color-gold);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid #E0E0E0;
      margin-bottom: 8px;
    }

    .faq-question {
      width: 100%;
      background: #F9F9F9;
      padding: 20px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border: none;
      text-align: left;
      font-size: 1rem;
      transition: 0.2s;
    }

    .faq-question:hover {
      background: #F0F0F0;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: white;
      padding: 0 20px;
      line-height: 1.8;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px;
    }

    .faq-item.active .faq-question {
      background: white;
      border-left: 4px solid var(--color-primary);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #C8102E 0%, #1A1A1A 100%);
      color: white;
      text-align: center;
      padding: 80px 0;
    }

    /* Footer */
    .footer {
      background: var(--color-dark);
      color: #CCCCCC;
      padding: 40px 0;
      font-size: 0.9rem;
    }

    .footer a:hover {
      color: var(--color-gold);
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .cards-grid, .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .nav-menu {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .hero-grid {
        flex-direction: column;
        text-align: center;
      }
      .hero-buttons {
        justify-content: center;
      }
      .cards-grid, .features-grid {
        grid-template-columns: 1fr;
      }
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      :root {
        --section-gap: 60px;
      }
    }