/* roulang page: index */
:root {
      --primary-red: #D42027;
      --primary-red-hover: #B01A20;
      --deep-blue: #0F1A2E;
      --warm-gold: #C8963E;
      --soft-bg: #F0F3F8;
      --white: #FFFFFF;
      --text-dark: #1E2A3A;
      --text-gray: #5A6A7E;
      --text-light: #8E9BAB;
      --border-light: #E8ECF1;
      --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.06);
      --shadow-md: 0 8px 30px rgba(0, 0, 0, 0.12);
      --shadow-lg: 0 15px 40px rgba(0, 0, 0, 0.15);
      --radius-md: 12px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", "Inter", sans-serif;
      --max-width: 1200px;
      --transition: all 0.3s ease;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      line-height: 1.7;
      color: var(--text-dark);
      background-color: var(--white);
      overflow-x: hidden;
    }

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

    /* 排版 */
    h1, h2, h3, h4 {
      font-weight: 700;
      line-height: 1.3;
    }
    h1 { font-size: 3rem; }
    h2 { font-size: 2rem; letter-spacing: -0.5px; }
    h3 { font-size: 1.25rem; }
    h4 { font-size: 1.1rem; }

    p {
      color: var(--text-gray);
      margin-bottom: 1.2rem;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    /* 按钮体系 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      cursor: pointer;
      border: 2px solid transparent;
      font-size: 1rem;
      min-width: 160px;
      text-align: center;
    }
    .btn-primary {
      background: var(--primary-red);
      color: white;
      border-color: var(--primary-red);
    }
    .btn-primary:hover {
      background: var(--primary-red-hover);
      border-color: var(--primary-red-hover);
      transform: translateY(-2px);
      box-shadow: var(--shadow-md);
    }
    .btn-outline {
      background: transparent;
      color: white;
      border-color: white;
    }
    .btn-outline:hover {
      background: white;
      color: var(--primary-red);
    }
    .btn-lg {
      padding: 16px 36px;
      font-size: 1.1rem;
      min-width: 200px;
    }

    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(10px);
      z-index: 1000;
      transition: var(--transition);
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    }
    .nav.scrolled {
      background: white;
      box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      height: 72px;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--deep-blue);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      color: var(--primary-red);
      font-size: 2rem;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      color: var(--text-dark);
      font-weight: 500;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-red);
      transition: width 0.2s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-cta {
      background: var(--primary-red);
      color: white !important;
      padding: 8px 20px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .nav-cta:hover {
      background: var(--primary-red-hover);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--deep-blue);
      background: none;
      border: none;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--deep-blue);
      padding: 24px;
      flex-direction: column;
      gap: 20px;
      z-index: 999;
      transform: translateY(-10px);
      opacity: 0;
      pointer-events: none;
      transition: 0.25s ease;
    }
    .mobile-menu.active {
      display: flex;
      transform: translateY(0);
      opacity: 1;
      pointer-events: auto;
    }
    .mobile-menu a {
      color: white;
      font-size: 1.2rem;
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 1px solid rgba(255,255,255,0.2);
    }

    /* Hero */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(15,26,46,0.75) 0%, rgba(15,26,46,0.85) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      padding: 0 24px;
    }
    .hero h1 {
      color: white;
      font-size: 3.2rem;
      margin-bottom: 20px;
      text-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }
    .hero .subtitle {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.9);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      color: white;
      font-size: 2rem;
      animation: bounce 2s infinite;
    }
    @keyframes bounce {
      0%,20%,50%,80%,100%{transform:translateY(0) translateX(-50%);}
      40%{transform:translateY(-10px) translateX(-50%);}
      60%{transform:translateY(-5px) translateX(-50%);}
    }

    /* 板块通用 */
    section {
      padding: 80px 0;
    }
    .section-header {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-header h2 {
      color: var(--deep-blue);
      margin-bottom: 12px;
    }
    .bg-soft {
      background: var(--soft-bg);
    }

    /* 核心优势 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 40px;
      text-align: center;
    }
    .stat-item i {
      font-size: 2.5rem;
      color: var(--primary-red);
      margin-bottom: 16px;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--deep-blue);
    }
    .stat-label {
      color: var(--text-gray);
      font-weight: 500;
    }

    /* 服务卡片 2x3 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: white;
      padding: 32px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .service-icon {
      font-size: 2.2rem;
      color: var(--primary-red);
      margin-bottom: 20px;
    }
    .service-card h3 {
      margin-bottom: 12px;
    }
    .service-desc {
      color: var(--text-gray);
      font-size: 0.95rem;
      flex:1;
    }
    .card-link {
      margin-top: 20px;
      color: var(--primary-red);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 案例双栏 */
    .case-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 60px;
    }
    .case-row.reverse {
      flex-direction: row-reverse;
    }
    .case-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-md);
    }
    .case-text {
      flex: 1;
    }
    .case-text h3 {
      margin-bottom: 16px;
    }
    .data-list {
      list-style: none;
      margin: 24px 0;
    }
    .data-list li {
      display: flex;
      align-items: baseline;
      gap: 8px;
      margin-bottom: 10px;
    }
    .data-number {
      font-size: 2rem;
      font-weight: 700;
      color: var(--primary-red);
    }

    /* 步骤条 */
    .steps {
      display: flex;
      justify-content: space-between;
      position: relative;
      margin-top: 40px;
    }
    .steps::before {
      content: '';
      position: absolute;
      top: 25px;
      left: 8%;
      width: 84%;
      height: 2px;
      background: repeating-linear-gradient(to right, var(--primary-red) 0px, var(--primary-red) 8px, transparent 8px, transparent 16px);
      z-index: 0;
    }
    .step {
      text-align: center;
      position: relative;
      z-index: 1;
      flex:1;
    }
    .step-circle {
      width: 50px;
      height: 50px;
      background: var(--primary-red);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.2rem;
      margin: 0 auto 16px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
    }
    .faq-question {
      padding: 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
    }
    .faq-answer {
      padding: 0 20px 20px;
      display: none;
      color: var(--text-gray);
      background: var(--soft-bg);
      margin: 0 10px 10px;
      border-radius: 8px;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-icon {
      font-size: 1.2rem;
      color: var(--primary-red);
    }

    /* CTA Banner */
    .cta-banner {
      background: var(--deep-blue);
      padding: 70px 0;
      text-align: center;
    }
    .cta-banner h2 {
      color: white;
    }

    /* Footer */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      padding: 60px 0 40px;
    }
    .footer-col p {
      color: var(--text-light);
      font-size: 0.95rem;
    }
    .footer-col h4 {
      margin-bottom: 16px;
      color: var(--deep-blue);
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 10px;
    }
    .footer-links a {
      color: var(--text-gray);
    }
    .copyright {
      background: #0A1220;
      color: rgba(255,255,255,0.7);
      text-align: center;
      padding: 20px;
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .case-row { flex-direction: column; gap: 30px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      h1 { font-size: 2.4rem; }
      .stats-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .steps { flex-direction: column; gap: 24px; }
      .steps::before { display: none; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero h1 { font-size: 2.4rem; }
    }
    @media (max-width: 520px) {
      .footer-grid { grid-template-columns: 1fr; }
    }