/* roulang page: index */
:root {
      --primary-brown: #3E2723;
      --gold: #C5A059;
      --burgundy: #7B2D3E;
      --bg-warm: #F9F6F1;
      --dark-bg: #2A1A17;
      --text-dark: #2c231f;
      --text-soft: #5e5048;
      --card-shadow: 0 4px 20px rgba(62,39,35,0.06);
      --hover-shadow: 0 12px 32px rgba(62,39,35,0.12);
      --radius: 8px;
      --transition: all 0.25s ease;
      --font-serif: 'Cinzel', 'Noto Serif SC', serif;
      --font-sans: 'Inter', 'PingFang SC', sans-serif;
      --container-max: 1280px;
      --nav-height: 80px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-dark);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

    h1, h2, h3, h4 {
      font-family: var(--font-serif);
      font-weight: 600;
      letter-spacing: 0.5px;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 500;
      border: none;
      background: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      white-space: nowrap;
    }

    /* 导航栏 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(62, 39, 35, 0.75);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(197, 160, 89, 0.25);
      transition: background 0.3s ease;
    }

    .main-header.scrolled {
      background: rgba(42, 26, 23, 0.96);
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: var(--nav-height);
    }

    .logo {
      font-family: var(--font-serif);
      font-weight: 800;
      font-size: 1.9rem;
      letter-spacing: 2px;
      color: var(--gold);
      text-transform: uppercase;
      line-height: 1;
      background: linear-gradient(135deg, #E0B868 0%, #C5A059 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }

    .nav-links a {
      color: #F9F6F1;
      font-weight: 500;
      font-size: 0.95rem;
      letter-spacing: 0.8px;
      position: relative;
      padding: 6px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--gold);
      transition: width 0.25s ease;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      color: #F9F6F1;
      font-size: 1.8rem;
    }

    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: rgba(42, 26, 23, 0.92);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-top: 1px solid rgba(197, 160, 89, 0.3);
      justify-content: space-around;
      padding: 12px 16px;
      z-index: 1001;
    }

    .mobile-bottom-nav a {
      color: #ccc;
      font-size: 0.75rem;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      transition: 0.2s;
    }

    .mobile-bottom-nav a i {
      font-size: 1.4rem;
    }

    .mobile-bottom-nav a.active {
      color: var(--gold);
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, rgba(30,18,15,0.85) 0%, rgba(62,39,35,0.7) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-blend-mode: overlay;
      position: relative;
      margin-top: 0;
      padding: 120px 0 80px;
    }

    .hero-content {
      max-width: 780px;
    }

    .hero h1 {
      font-size: clamp(2.8rem, 6vw, 4rem);
      font-weight: 700;
      color: #F9F6F1;
      line-height: 1.25;
      margin-bottom: 24px;
      text-shadow: 0 4px 12px rgba(0,0,0,0.4);
    }

    .hero .subtitle {
      font-size: 1.25rem;
      color: #e0d3c5;
      margin-bottom: 36px;
      max-width: 600px;
      font-weight: 400;
    }

    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
    }

    .btn-primary {
      background: var(--burgundy);
      color: white;
      padding: 14px 36px;
      border-radius: 6px;
      font-weight: 600;
      font-size: 1rem;
      box-shadow: 0 6px 18px rgba(123,45,62,0.4);
      letter-spacing: 0.5px;
    }

    .btn-primary:hover {
      background: #962f47;
      transform: translateY(-2px);
      box-shadow: 0 12px 28px rgba(123,45,62,0.5);
    }

    .btn-outline {
      border: 2px solid var(--gold);
      color: var(--gold);
      padding: 14px 36px;
      border-radius: 6px;
      font-weight: 600;
      background: transparent;
    }

    .btn-outline:hover {
      background: rgba(197, 160, 89, 0.15);
      color: #f0d89c;
    }

    /* 板块标题 */
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }

    .section-title h2 {
      font-size: 2.5rem;
      color: var(--primary-brown);
      margin-bottom: 12px;
    }

    .gold-line {
      width: 70px;
      height: 3px;
      background: var(--gold);
      margin: 16px auto;
    }

    .section-desc {
      color: var(--text-soft);
      max-width: 650px;
      margin: 0 auto;
      font-size: 1.1rem;
    }

    /* 核心优势 非对称网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }

    .feature-item {
      background: white;
      padding: 32px 24px;
      border-radius: var(--radius);
      box-shadow: var(--card-shadow);
      transition: var(--transition);
      border: 1px solid transparent;
    }

    .feature-item:hover {
      transform: translateY(-6px);
      box-shadow: var(--hover-shadow);
      border-color: var(--gold);
    }

    .feature-icon {
      font-size: 2.4rem;
      color: var(--gold);
      margin-bottom: 20px;
    }

    .feature-item h3 {
      font-size: 1.4rem;
      margin-bottom: 12px;
      color: var(--primary-brown);
    }

    /* 服务宽卡 */
    .service-card {
      display: flex;
      background: white;
      border-radius: var(--radius);
      overflow: hidden;
      margin-bottom: 36px;
      box-shadow: var(--card-shadow);
      transition: var(--transition);
    }

    .service-card.reverse {
      flex-direction: row-reverse;
    }

    .service-card:hover {
      box-shadow: var(--hover-shadow);
    }

    .service-text {
      flex: 1 1 60%;
      padding: 48px 40px;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .service-img {
      flex: 1 1 40%;
      background: #eae1d5;
      min-height: 280px;
    }

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

    .service-text h3 {
      font-size: 1.8rem;
      color: var(--primary-brown);
      margin-bottom: 16px;
    }

    .text-link {
      color: var(--burgundy);
      font-weight: 600;
      margin-top: 16px;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    /* 数据滚动条 */
    .data-strip {
      background: #f3ede6;
      padding: 48px 0;
      overflow-x: auto;
      white-space: nowrap;
    }

    .data-track {
      display: flex;
      gap: 64px;
      justify-content: center;
      min-width: max-content;
    }

    .data-item {
      text-align: center;
    }

    .data-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--burgundy);
      font-family: var(--font-serif);
    }

    .data-label {
      color: var(--text-soft);
      font-weight: 500;
    }

    /* 解决方案卡片 */
    .solutions-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .solution-card {
      background: white;
      padding: 32px 24px;
      border-radius: var(--radius);
      box-shadow: var(--card-shadow);
      position: relative;
    }

    .step-badge {
      position: absolute;
      top: -16px;
      left: 24px;
      background: var(--gold);
      color: #2A1A17;
      font-weight: 700;
      width: 40px;
      height: 40px;
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      font-family: var(--font-serif);
    }

    .tech-tags {
      margin-top: 20px;
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
    }

    .tag {
      background: #f0e7db;
      color: var(--primary-brown);
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
    }

    /* FAQ */
    .faq-wrapper {
      display: grid;
      grid-template-columns: 240px 1fr;
      gap: 40px;
    }

    .faq-categories {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .cat-btn {
      background: transparent;
      border: 1px solid #d9cdbc;
      padding: 12px 20px;
      border-radius: 30px;
      color: var(--text-dark);
      text-align: left;
    }

    .cat-btn.active {
      background: var(--gold);
      border-color: var(--gold);
      color: #2A1A17;
      font-weight: 600;
    }

    .accordion-item {
      border-bottom: 1px solid #ddd3c4;
      padding: 18px 0;
    }

    .accordion-header {
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }

    /* CTA */
    .cta-dark {
      background: var(--dark-bg);
      padding: 80px 0;
      text-align: center;
      color: #F9F6F1;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0;
    }

    .footer-brand p {
      color: #c4b5a6;
      margin: 16px 0;
    }

    .footer-links a {
      display: block;
      color: #c4b5a6;
      margin-bottom: 10px;
    }

    .social-icons i {
      font-size: 1.6rem;
      margin-right: 18px;
      color: var(--gold);
    }

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

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-toggle { display: block; }
      .mobile-bottom-nav { display: flex; }
      .hero { padding: 100px 0 60px; }
      .service-card, .service-card.reverse { flex-direction: column; }
      .features-grid { grid-template-columns: 1fr; }
      .solutions-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }