/* roulang page: index */
:root {
      --primary: #1A1A2E;
      --accent: #E94560;
      --accent-hover: #C23152;
      --ocean: #0F3460;
      --bg-light: #F8F9FA;
      --white: #FFFFFF;
      --card-bg: #FFFFFF;
      --text-primary: #1A1A2E;
      --text-secondary: #4A4A6A;
      --text-muted: #9CA3AF;
      --border-light: #E5E7EB;
      --success: #2ECC71;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      --shadow-sm: 0 4px 20px rgba(26,26,46,0.06);
      --shadow-md: 0 8px 30px rgba(26,26,46,0.12);
      --shadow-xl: 0 12px 40px rgba(26,26,46,0.18);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      --font-number: "Inter", "Roboto", "Segoe UI", sans-serif;
      --transition: 0.3s ease;
      --header-height: 76px;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--header-height);
    }

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

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      background: none;
      font-weight: 600;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      border-radius: var(--radius-sm);
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      line-height: 1.3;
    }

    h1 {
      font-size: 48px;
      font-weight: 800;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 32px;
      font-weight: 700;
      margin-bottom: 16px;
    }

    h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    p {
      color: var(--text-secondary);
      margin-bottom: 16px;
    }

    .section {
      padding: 120px 0;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      z-index: 1000;
      border-bottom: 1px solid transparent;
      transition: box-shadow 0.3s, border-color 0.3s;
      display: flex;
      align-items: center;
    }
    .header.scrolled {
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
      border-bottom: 1px solid var(--border-light);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 800;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 1px;
    }
    .logo-icon {
      font-size: 28px;
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
      border-radius: 2px;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(233,69,96,0.3);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 18px rgba(233,69,96,0.4);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--ocean);
      color: var(--ocean);
      padding: 12px 28px;
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--ocean);
      color: white;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 26px;
      height: 3px;
      background: var(--primary);
      border-radius: 3px;
      transition: 0.3s;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(20px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 36px;
      z-index: 999;
      font-size: 20px;
      font-weight: 600;
    }
    .mobile-menu a {
      color: var(--primary);
    }
    .mobile-menu .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 32px;
      color: var(--primary);
    }

    /* Hero */
    .hero {
      padding: 160px 0 120px;
      background: var(--white);
      display: flex;
      align-items: center;
      min-height: 90vh;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-text h1 {
      margin-bottom: 20px;
    }
    .hero-text .subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-lg);
      height: 420px;
      position: relative;
      overflow: hidden;
      box-shadow: var(--shadow-xl);
    }
    .hero-visual::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(26,26,46,0.5);
      backdrop-filter: blur(2px);
      border-radius: var(--radius-lg);
    }
    .visual-overlay {
      position: absolute;
      top: 20px;
      right: 20px;
      background: rgba(255,255,255,0.15);
      backdrop-filter: blur(8px);
      padding: 16px 24px;
      border-radius: var(--radius-md);
      color: white;
      font-weight: 700;
      z-index: 2;
      font-family: var(--font-number);
      font-size: 24px;
    }

    /* 核心优势 非对称 */
    .features-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      margin-top: 48px;
    }
    .feature-large {
      grid-row: span 2;
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 36px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border-left: 4px solid transparent;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .feature-large:hover {
      box-shadow: var(--shadow-md);
      border-left-color: var(--accent);
      transform: translateY(-4px);
    }
    .feature-small {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border-left: 4px solid transparent;
    }
    .feature-small:hover {
      box-shadow: var(--shadow-md);
      border-left-color: var(--accent);
      transform: translateY(-4px);
    }
    .feature-icon {
      font-size: 36px;
      color: var(--accent);
      margin-bottom: 16px;
    }
    .feature-large img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      border-radius: var(--radius-sm);
      margin-top: 20px;
    }

    /* 服务卡片 */
    .service-tags {
      display: flex;
      gap: 12px;
      margin-bottom: 40px;
      flex-wrap: wrap;
    }
    .service-tag {
      padding: 8px 20px;
      background: #EDF2F7;
      border-radius: 20px;
      font-weight: 500;
      cursor: pointer;
      transition: 0.2s;
    }
    .service-tag.active {
      background: var(--accent);
      color: white;
    }
    .services-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 24px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .service-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .service-card img {
      width: 100%;
      height: 180px;
      object-fit: cover;
    }
    .service-info {
      padding: 20px;
    }

    /* 数据深色条 */
    .stats {
      background: var(--primary);
      padding: 80px 0;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    .stat-number {
      font-size: 56px;
      font-weight: 800;
      color: var(--accent);
      font-family: var(--font-number);
      line-height: 1.1;
    }
    .stat-label {
      color: rgba(255,255,255,0.8);
      margin-top: 8px;
      font-size: 16px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-md);
    }
    .case-img {
      position: relative;
      overflow: hidden;
      height: 200px;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.04);
    }
    .case-content {
      padding: 20px;
    }
    .case-tag {
      background: #FEE2E2;
      color: var(--accent);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
      display: inline-block;
      margin-bottom: 8px;
    }

    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      margin-top: 48px;
      position: relative;
    }
    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }
    .step-circle {
      width: 48px;
      height: 48px;
      background: var(--accent);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 20px;
      margin: 0 auto 16px;
      z-index: 2;
      position: relative;
    }
    .step::after {
      content: '';
      position: absolute;
      top: 24px;
      left: calc(50% + 24px);
      width: calc(100% - 48px);
      height: 2px;
      border-top: 2px dashed var(--border-light);
      z-index: 1;
    }
    .step:last-child::after {
      display: none;
    }

    /* FAQ */
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
      background: white;
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #F9FAFB;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      background: #F8F9FA;
      padding: 0 24px;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
    }
    .faq-icon {
      color: var(--accent);
    }

    /* CTA */
    .cta-section {
      background: var(--primary);
      padding: 100px 0;
      text-align: center;
    }
    .cta-title {
      color: white;
      margin-bottom: 16px;
    }
    .cta-sub {
      color: #CBD5E1;
      margin-bottom: 32px;
    }
    .cta-form {
      display: flex;
      justify-content: center;
      gap: 12px;
      flex-wrap: wrap;
    }
    .cta-input {
      padding: 14px 20px;
      border-radius: var(--radius-sm);
      border: 1px solid #D1D5DB;
      min-width: 260px;
      outline: none;
    }
    .cta-input:focus {
      border-color: var(--accent);
      box-shadow: 0 0 0 3px rgba(233,69,96,0.15);
    }

    /* Footer */
    .footer {
      background: #F3F4F6;
      border-top: 4px solid var(--accent);
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .copyright {
      text-align: center;
      color: var(--text-muted);
      font-size: 13px;
      border-top: 1px solid var(--border-light);
      padding-top: 24px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      .hero-grid { grid-template-columns: 1fr; gap: 40px; }
      .cases-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-links, .header .btn-primary { display: none; }
      .hamburger { display: flex; }
      h1 { font-size: 32px; }
      .section { padding: 80px 0; }
      .features-grid { grid-template-columns: 1fr; }
      .feature-large { grid-row: auto; }
      .services-grid { grid-template-columns: 1fr; }
      .process-steps { flex-direction: column; gap: 40px; }
      .step::after { display: none; }
      .cases-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .stat-number { font-size: 40px; }
    }