/* roulang page: index */
:root {
      --brand-red: #E63946;
      --deep-navy: #1D3557;
      --ice-cyan: #A8DADC;
      --off-white: #F1FAEE;
      --text-dark: #2B2D42;
      --text-mid: #8D99AE;
      --white: #FFFFFF;
      --border-light: #D1D5DB;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 12px 24px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 30px;
      --radius-input: 8px;
      --transition: 0.25s ease;
      --max-width: 1200px;
      --section-gap: 100px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Roboto', sans-serif;
      background-color: var(--off-white);
      color: var(--text-dark);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-weight: 600;
      letter-spacing: -0.02em;
      color: var(--text-dark);
    }

    h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.15;
      margin-bottom: 1.2rem;
    }

    h2 {
      font-size: 34px;
      margin-bottom: 1rem;
      position: relative;
      display: inline-block;
    }

    h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 0.5rem;
    }

    .section-title {
      margin-bottom: 2.5rem;
    }

    .section-title h2 {
      margin-bottom: 0.5rem;
    }

    .section-subtitle {
      font-size: 1.1rem;
      color: var(--text-mid);
      max-width: 700px;
      margin: 0 auto 2rem;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* 导航栏 */
    .site-header {
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.04);
      position: sticky;
      top: 0;
      z-index: 99;
      transition: box-shadow var(--transition);
    }

    .site-header.scrolled {
      box-shadow: 0 4px 15px rgba(0,0,0,0.06);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 75px;
    }

    .logo {
      font-size: 1.7rem;
      font-weight: 700;
      color: var(--text-dark);
      display: flex;
      align-items: center;
      gap: 0.3rem;
      letter-spacing: -0.5px;
    }

    .logo span {
      color: var(--brand-red);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2.5rem;
      list-style: none;
      margin: 0;
    }

    .nav-menu a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-dark);
      text-decoration: none;
      padding: 0.4rem 0;
      border-bottom: 2px solid transparent;
      transition: all var(--transition);
      text-transform: uppercase;
      letter-spacing: 0.3px;
    }

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

    .nav-cta {
      background-color: var(--brand-red);
      color: white !important;
      padding: 0.6rem 1.8rem !important;
      border-radius: var(--radius-btn);
      border: none !important;
      font-weight: 600;
      box-shadow: 0 8px 16px rgba(230,57,70,0.25);
      transition: all var(--transition);
    }

    .nav-cta:hover {
      background-color: #C1121F;
      box-shadow: 0 12px 20px rgba(230,57,70,0.35);
      transform: translateY(-1px);
      color: white !important;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      cursor: pointer;
      gap: 5px;
    }

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--text-dark);
      border-radius: 2px;
      transition: 0.2s;
    }

    /* Hero */
    .hero {
      padding: 3rem 0 5rem;
      background: linear-gradient(180deg, #FFFFFF 0%, var(--off-white) 100%);
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }

    .hero-content {
      flex: 0 0 50%;
    }

    .hero-content h1 {
      color: var(--text-dark);
      margin-bottom: 1.2rem;
    }

    .hero-highlight {
      color: var(--brand-red);
      position: relative;
    }

    .hero-desc {
      font-size: 1.2rem;
      color: var(--text-mid);
      margin-bottom: 2.5rem;
      line-height: 1.6;
    }

    .hero-buttons {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.9rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: all var(--transition);
      border: 2px solid transparent;
      font-size: 1rem;
      letter-spacing: 0.3px;
      cursor: pointer;
    }

    .btn-primary {
      background: var(--brand-red);
      color: white;
      border-color: var(--brand-red);
      box-shadow: 0 10px 20px rgba(230,57,70,0.3);
    }

    .btn-primary:hover {
      background: #C1121F;
      border-color: #C1121F;
      box-shadow: 0 14px 28px rgba(230,57,70,0.4);
      transform: translateY(-2px);
      color: white;
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--deep-navy);
      color: var(--deep-navy);
    }

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

    .hero-visual {
      flex: 0 0 48%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: 28px;
      height: 420px;
      position: relative;
      box-shadow: 0 25px 40px -15px rgba(0,0,0,0.25);
      overflow: hidden;
    }

    .data-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(0deg, rgba(29,53,87,0.9) 0%, transparent 100%);
      padding: 2rem;
      color: white;
      display: flex;
      justify-content: space-around;
    }

    .live-badge {
      background: var(--ice-cyan);
      color: var(--deep-navy);
      padding: 0.25rem 1rem;
      border-radius: 20px;
      font-weight: 700;
      font-size: 0.9rem;
    }

    /* 数据看板 */
    .dashboard {
      padding: var(--section-gap) 0;
      background: var(--white);
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.8rem;
    }

    .stat-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
      border: 1px solid rgba(0,0,0,0.02);
      text-align: center;
    }

    .stat-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }

    .stat-label {
      font-size: 0.9rem;
      text-transform: uppercase;
      letter-spacing: 0.5px;
      color: var(--text-mid);
      margin-bottom: 0.8rem;
    }

    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      font-family: 'Inter', 'Roboto', monospace;
      color: var(--brand-red);
      line-height: 1.1;
      margin-bottom: 0.5rem;
    }

    .stat-trend {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 0.3rem;
      color: var(--deep-navy);
      font-size: 0.9rem;
    }

    /* 服务矩阵 */
    .services {
      padding: var(--section-gap) 0;
      background: var(--off-white);
    }

    .service-matrix {
      display: grid;
      grid-template-columns: 1.2fr 0.9fr;
      gap: 1.8rem;
    }

    .service-card {
      border-radius: var(--radius-card);
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
      color: white;
      display: flex;
      flex-direction: column;
      justify-content: flex-end;
      min-height: 320px;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
    }

    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }

    .card-overlay {
      background: linear-gradient(0deg, rgba(29,53,87,0.92) 0%, rgba(29,53,87,0.4) 100%);
      padding: 2rem;
      height: 100%;
      display: flex;
      flex-direction: column;
      justify-content: flex-end;
    }

    .service-card.large {
      background-image: url('/assets/images/coverpic/cover-2.webp');
    }

    .small-stack {
      display: flex;
      flex-direction: column;
      gap: 1.8rem;
    }

    .service-card.small {
      min-height: 150px;
    }

    .service-card.s1 {
      background-image: url('/assets/images/coverpic/cover-3.webp');
    }

    .service-card.s2 {
      background-image: url('/assets/images/coverpic/cover-4.webp');
    }

    /* 案例对比 */
    .cases {
      padding: var(--section-gap) 0;
      background: var(--white);
    }

    .comparison {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0;
      background: #f8fafc;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .compare-col {
      padding: 2.5rem;
    }

    .compare-col.old {
      background: #f1f5f9;
    }

    .compare-col.new {
      background: #e6f7f9;
    }

    .compare-list {
      list-style: none;
      margin: 1.5rem 0 0;
      padding: 0;
    }

    .compare-list li {
      display: flex;
      align-items: center;
      gap: 0.8rem;
      margin-bottom: 1.3rem;
      font-weight: 500;
    }

    .icon-red {
      color: var(--brand-red);
      font-size: 1.3rem;
    }

    .icon-green {
      color: #2a9d8f;
      font-size: 1.3rem;
    }

    .client-logos {
      display: flex;
      justify-content: center;
      gap: 2.5rem;
      margin-top: 3rem;
      filter: grayscale(1);
      opacity: 0.7;
    }

    /* FAQ */
    .faq {
      padding: var(--section-gap) 0;
      background: var(--off-white);
    }

    .accordion-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 1rem;
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }

    .accordion-header {
      padding: 1.4rem 2rem;
      display: flex;
      align-items: center;
      gap: 1.2rem;
      cursor: pointer;
      font-weight: 600;
      background: white;
      transition: background 0.2s;
    }

    .accordion-header i {
      font-size: 1.4rem;
      color: var(--brand-red);
    }

    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #f9fafb;
      padding: 0 2rem;
    }

    .accordion-content p {
      padding: 1rem 0 1.5rem;
      margin: 0;
    }

    /* 表单 */
    .contact {
      padding: var(--section-gap) 0;
      background: var(--white);
    }

    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }

    .contact-info h3 {
      font-size: 2rem;
    }

    .trust-badge {
      background: var(--deep-navy);
      color: white;
      display: inline-block;
      padding: 0.5rem 1.5rem;
      border-radius: 20px;
      margin-top: 1rem;
    }

    .contact-form input,
    .contact-form textarea {
      width: 100%;
      padding: 1rem;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-input);
      margin-bottom: 1rem;
      transition: all 0.2s;
    }

    .contact-form input:focus,
    .contact-form textarea:focus {
      outline: none;
      border-color: var(--brand-red);
      box-shadow: 0 0 0 3px rgba(230,57,70,0.2);
    }

    .btn-submit {
      width: 100%;
      background: var(--brand-red);
      color: white;
      border: none;
      font-weight: 700;
    }

    /* 页脚 */
    .footer {
      background: var(--deep-navy);
      color: #ccd6e0;
      padding: 4rem 0 1.5rem;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
    }

    .footer a {
      color: #a0b3cc;
      text-decoration: none;
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 2.5rem;
      padding-top: 1.5rem;
      text-align: center;
      color: #8b9bb5;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 42px; }
      .hero-grid { flex-direction: column; }
      .hero-visual { width: 100%; height: 350px; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .service-matrix { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .nav-menu { display: none; flex-direction: column; position: absolute; top: 75px; left: 0; width: 100%; background: white; padding: 1rem; box-shadow: 0 10px 15px rgba(0,0,0,0.05); }
      .nav-menu.active { display: flex; }
      .hamburger { display: flex; }
      .stats-grid { grid-template-columns: 1fr; }
      .comparison { grid-template-columns: 1fr; }
      .contact-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      h1 { font-size: 36px; }
    }

    @media (max-width: 520px) {
      .footer-grid { grid-template-columns: 1fr; }
    }