/* roulang page: index */
:root {
      --primary: #FF4D00;
      --primary-dark: #CC3D00;
      --primary-hover: #E64400;
      --secondary: #2D2D2D;
      --accent: #00C2FF;
      --bg-white: #FFFFFF;
      --bg-light: #F8F8F8;
      --text-dark: #1A1A1A;
      --text-mid: #666666;
      --text-light: #999999;
      --text-cta: #CCCCCC;
      --success: #00C853;
      --old-scheme: #9E9E9E;
      --border-light: #E8E8E8;
      --border-input: #555555;
      --footer-bg: #1A1A1A;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 8px 30px rgba(0, 0, 0, 0.12);
      --shadow-btn: 0 6px 20px rgba(255, 77, 0, 0.3);
      --transition: 0.3s ease;
      --font-stack: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-number: "DIN Alternate", "Arial", sans-serif;
      --max-width: 1280px;
      --header-height-desktop: 72px;
      --header-height-mobile: 56px;
    }

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

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

    body {
      font-family: var(--font-stack);
      font-size: 16px;
      font-weight: 400;
      line-height: 1.7;
      color: var(--text-dark);
      background-color: var(--bg-white);
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

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

    button, input {
      font-family: var(--font-stack);
      outline: none;
    }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: var(--header-height-desktop);
      display: flex;
      align-items: center;
      transition: background-color var(--transition), backdrop-filter var(--transition), box-shadow var(--transition);
      background-color: transparent;
      backdrop-filter: blur(0px);
    }

    .header.scrolled {
      background-color: rgba(45, 45, 45, 0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }

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

    .logo {
      font-size: 24px;
      font-weight: 700;
      letter-spacing: 1px;
      color: #FF4D00;
      display: flex;
      align-items: baseline;
      gap: 6px;
    }
    .logo .logo-small {
      font-size: 14px;
      font-weight: 500;
      color: #CCCCCC;
      letter-spacing: 0.5px;
    }
    .header.scrolled .logo .logo-small {
      color: #AAAAAA;
    }

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

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: #1A1A1A;
      position: relative;
      padding: 8px 0;
      transition: color var(--transition);
    }
    .header.scrolled .nav-links a {
      color: #FFFFFF;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: #FF4D00;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: #FF4D00;
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: #1A1A1A;
      transition: var(--transition);
    }
    .header.scrolled .hamburger span {
      background: #FFFFFF;
    }

    /* 移动端导航 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(45, 45, 45, 0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      z-index: 999;
      transform: translateX(100%);
      transition: transform 0.4s ease;
    }
    .mobile-menu.open {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 24px;
      font-weight: 600;
      color: #FFFFFF;
      transition: color var(--transition);
    }
    .mobile-menu a:hover {
      color: #FF4D00;
    }

    /* Hero */
    .hero {
      background: var(--secondary);
      position: relative;
      overflow: hidden;
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding-top: var(--header-height-desktop);
    }
    .hero::before {
      content: '';
      position: absolute;
      top: -20%;
      left: -20%;
      width: 140%;
      height: 140%;
      background: radial-gradient(circle at 30% 40%, rgba(255,77,0,0.15) 0%, rgba(45,45,45,0) 70%);
      animation: heroGlow 8s ease-in-out infinite alternate;
    }
    @keyframes heroGlow {
      0% { transform: scale(1); opacity: 0.6; }
      100% { transform: scale(1.1); opacity: 1; }
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: 48px;
      font-weight: 700;
      letter-spacing: 2px;
      color: #FFFFFF;
      margin-bottom: 20px;
      line-height: 1.2;
    }
    .hero-sub {
      font-size: 18px;
      color: #CCCCCC;
      margin-bottom: 36px;
      display: flex;
      gap: 24px;
      flex-wrap: wrap;
    }
    .hero-sub span {
      white-space: nowrap;
    }
    .btn-primary {
      background: var(--primary);
      color: #FFFFFF;
      border: none;
      border-radius: var(--radius-btn);
      padding: 14px 36px;
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      transition: all 0.25s ease;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: var(--shadow-btn);
      color: #FFFFFF;
    }
    .btn-primary:active {
      background: var(--primary-dark);
      transform: translateY(0);
    }
    .btn-link {
      color: var(--accent);
      font-weight: 500;
      margin-left: 24px;
      transition: color var(--transition);
      display: inline-block;
    }
    .btn-link:hover {
      color: #FFFFFF;
      text-decoration: underline;
    }
    .hero-image {
      flex: 1;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    /* 通用板块 */
    .section {
      padding: 120px 0;
    }
    .section-light {
      background: var(--bg-light);
    }
    .section-title {
      font-size: 36px;
      font-weight: 600;
      letter-spacing: 1px;
      color: var(--text-dark);
      text-align: center;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 50%;
      transform: translateX(-50%);
      width: 60px;
      height: 4px;
      background: var(--primary);
      border-radius: 2px;
    }
    .title-wrapper {
      text-align: center;
      margin-bottom: 64px;
    }

    /* 数据看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      padding: 32px 24px;
      text-align: center;
      box-shadow: var(--shadow-card);
      border: none;
      transition: all var(--transition);
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 56px;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 8px;
    }
    .stat-card:nth-child(3) .stat-number,
    .stat-card:nth-child(4) .stat-number {
      color: var(--accent);
    }
    .stat-label {
      font-size: 13px;
      font-weight: 500;
      color: var(--text-mid);
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .dashboard-cta {
      text-align: center;
      margin-top: 40px;
    }

    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      padding: 32px;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-card);
      display: flex;
      gap: 24px;
      align-items: flex-start;
      transition: all var(--transition);
      cursor: default;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: var(--primary);
    }
    .service-icon {
      width: 30%;
      flex-shrink: 0;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .service-icon i {
      font-size: 48px;
      color: var(--primary);
    }
    .service-content {
      width: 70%;
    }
    .service-content h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--secondary);
      margin-bottom: 12px;
    }
    .service-content p {
      color: var(--text-mid);
      font-size: 15px;
      margin-bottom: 16px;
    }
    .service-link {
      color: var(--primary);
      font-weight: 500;
    }

    /* 对比区 */
    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      align-items: start;
    }
    .compare-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      padding: 36px;
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
    }
    .compare-old {
      background: #EEEEEE;
      border: 1px solid #DDD;
    }
    .compare-new {
      border: 2px solid var(--success);
      box-shadow: 0 8px 30px rgba(0,200,83,0.1);
    }
    .compare-label {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .compare-old .compare-label {
      color: var(--old-scheme);
      text-decoration: line-through;
    }
    .compare-new .compare-label {
      color: var(--success);
    }
    .compare-list {
      list-style: none;
    }
    .compare-list li {
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 16px;
    }
    .compare-old li {
      color: #999999;
    }
    .compare-new li {
      color: var(--text-dark);
      font-weight: 500;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .case-card {
      background: #FFFFFF;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      position: relative;
      height: 200px;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s ease;
    }
    .case-card:hover .case-img img {
      transform: scale(1.05);
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      background: linear-gradient(to top, rgba(0,0,0,0.7), transparent);
      padding: 20px;
    }
    .case-overlay h3 {
      color: #FFFFFF;
      font-size: 20px;
      font-weight: 600;
    }
    .case-body {
      padding: 24px;
    }
    .case-body p {
      color: var(--text-mid);
      margin-bottom: 12px;
    }
    .case-highlight {
      font-weight: 700;
      color: var(--primary);
    }
    .case-tag {
      display: inline-block;
      background: #F0F0F0;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 12px;
      color: var(--text-mid);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: #FFFFFF;
      border-radius: 8px;
      margin-bottom: 8px;
      box-shadow: 0 2px 10px rgba(0,0,0,0.04);
      overflow: hidden;
    }
    .faq-question {
      padding: 20px;
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: color var(--transition);
    }
    .faq-question i {
      transition: transform 0.3s ease;
    }
    .faq-item.active .faq-question {
      color: var(--primary);
    }
    .faq-item.active .faq-question i {
      transform: rotate(45deg);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      padding: 0 20px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 0 20px 20px 20px;
    }

    /* CTA */
    .cta-section {
      background: var(--secondary);
      position: relative;
      background-image: repeating-linear-gradient(45deg, rgba(255,255,255,0.02) 0px, rgba(255,255,255,0.02) 2px, transparent 2px, transparent 8px);
    }
    .cta-title {
      color: #FFFFFF;
      font-size: 36px;
      font-weight: 600;
      text-align: center;
    }
    .cta-sub {
      color: #CCCCCC;
      text-align: center;
      margin-bottom: 36px;
    }
    .cta-form {
      display: flex;
      gap: 16px;
      max-width: 600px;
      margin: 0 auto;
      flex-wrap: wrap;
    }
    .cta-input {
      flex: 1;
      background: #FFFFFF;
      border: 1px solid var(--border-input);
      border-radius: var(--radius-btn);
      padding: 14px 20px;
      font-size: 16px;
    }
    .cta-note {
      text-align: center;
      color: #999999;
      font-size: 13px;
      margin-top: 16px;
    }

    /* Footer */
    .footer {
      background: var(--footer-bg);
      color: #CCCCCC;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }
    .footer-logo {
      font-size: 24px;
      font-weight: 700;
      color: #FF4D00;
      margin-bottom: 12px;
    }
    .footer-desc {
      color: #AAAAAA;
      margin-bottom: 20px;
    }
    .social-icons i {
      font-size: 20px;
      margin-right: 16px;
      color: #777;
      transition: color var(--transition);
      cursor: pointer;
    }
    .social-icons i:hover {
      color: var(--primary);
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 12px;
    }
    .footer-links a {
      color: #CCCCCC;
      transition: color var(--transition);
    }
    .footer-links a:hover {
      color: var(--primary);
    }
    .footer-contact p {
      margin-bottom: 8px;
    }
    .footer-bottom {
      border-top: 1px solid #333;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 13px;
      color: #777777;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .dashboard-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .cases-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-text h1 { font-size: 40px; }
      .comparison-wrapper { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .cta-form { flex-direction: column; }
    }
    @media (max-width: 480px) {
      .hero-text h1 { font-size: 32px; }
      .section-title { font-size: 26px; }
      .dashboard-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .cases-grid { grid-template-columns: 1fr; }
      .stat-number { font-size: 40px; }
    }