/* roulang page: index */
:root {
      --deep-blue: #1A2A3A;
      --amber-gold: #D4A843;
      --warm-white: #F7F5F2;
      --pure-white: #ffffff;
      --text-dark: #1e1e1e;
      --text-muted: #5A5A5A;
      --text-light: #8A8A8A;
      --border-light: #E8E6E1;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-btn: 8px;
      --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --spacing-section: 100px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--warm-white);
      color: var(--text-dark);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(10px);
      -webkit-backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(26,42,58,0.06);
      transition: box-shadow 0.3s;
    }
    .header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      background: rgba(255,255,255,0.9);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 28px;
      font-weight: 800;
      color: var(--deep-blue);
      letter-spacing: -0.5px;
      display: flex;
      align-items: baseline;
      gap: 4px;
    }
    .logo small {
      font-size: 12px;
      font-weight: 400;
      color: var(--text-light);
      letter-spacing: 0.5px;
      margin-left: 4px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-dark);
      position: relative;
      padding: 4px 0;
      font-size: 15px;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--amber-gold);
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--amber-gold);
      color: var(--deep-blue) !important;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 14px;
      transition: all 0.25s;
      display: inline-block;
      border: none;
      cursor: pointer;
      letter-spacing: 0.3px;
    }
    .btn-primary:hover {
      background: #c99b3a;
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(212,168,67,0.25);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--amber-gold);
      color: var(--amber-gold);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 14px;
      transition: 0.25s;
      display: inline-block;
      cursor: pointer;
    }
    .btn-outline:hover {
      background: var(--amber-gold);
      color: var(--deep-blue);
      transform: translateY(-2px);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--deep-blue);
      border-radius: 2px;
      transition: 0.3s;
    }
    /* 英雄区 */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #1A2A3A 0%, #0F1F2E 100%);
      position: relative;
      overflow: hidden;
      padding-top: 72px;
    }
    .hero::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: repeating-linear-gradient(45deg, rgba(255,255,255,0.02) 0px, rgba(255,255,255,0.02) 2px, transparent 2px, transparent 8px);
      pointer-events: none;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
      flex-wrap: wrap;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1 1 400px;
      color: white;
    }
    .hero-text h1 {
      font-size: 52px;
      font-weight: 800;
      line-height: 1.2;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }
    .hero-text .sub {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1 1 400px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 360px;
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
      opacity: 0.9;
    }
    /* 板块通用 */
    section {
      padding: var(--spacing-section) 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 48px;
      height: 4px;
      background: var(--amber-gold);
      border-radius: 2px;
    }
    .bg-white {
      background: var(--pure-white);
    }
    /* 服务卡片 - 4列不等高 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .service-card {
      background: var(--pure-white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
      border: 1px solid var(--border-light);
    }
    .service-card.featured {
      background: linear-gradient(180deg, #FFF9ED 0%, #ffffff 100%);
      border-color: var(--amber-gold);
      transform: scale(1.02);
    }
    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
    }
    .service-icon {
      font-size: 32px;
      color: var(--amber-gold);
      margin-bottom: 20px;
    }
    .service-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .service-desc {
      color: var(--text-muted);
      font-size: 15px;
      flex: 1;
      margin-bottom: 20px;
    }
    .learn-more {
      color: var(--amber-gold);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: gap 0.2s;
    }
    .learn-more:hover {
      gap: 12px;
    }
    /* 优势数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .stat-item {
      background: #EEECEA;
      padding: 28px 16px;
      border-radius: var(--radius-card);
      text-align: center;
      transition: 0.3s;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      background: linear-gradient(135deg, var(--amber-gold), var(--deep-blue));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1.2;
    }
    .stat-label {
      color: var(--text-muted);
      margin-top: 8px;
    }
    /* 案例 2x2 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
      margin-top: 40px;
    }
    .case-card {
      background: var(--pure-white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
      position: relative;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img {
      transform: scale(1.05);
    }
    .case-tag {
      position: absolute;
      bottom: 16px;
      left: 16px;
      background: rgba(26,42,58,0.8);
      color: white;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 13px;
      backdrop-filter: blur(4px);
    }
    .case-body {
      padding: 20px;
    }
    /* 解决方案交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-top: 60px;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-text {
      flex: 1;
    }
    .solution-img {
      flex: 1;
      min-height: 300px;
      background-size: cover;
      border-radius: 20px;
    }
    .icon-list {
      list-style: none;
      margin: 20px 0;
    }
    .icon-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 12px;
      color: var(--text-dark);
    }
    .icon-list li::before {
      content: '';
      width: 8px;
      height: 8px;
      background: var(--amber-gold);
      border-radius: 50%;
      flex-shrink: 0;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
    }
    .faq-question {
      background: #F1EFEC;
      padding: 18px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
      border-radius: 8px;
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      background: white;
      padding: 0 24px;
      color: var(--text-muted);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
    }
    .faq-item.open .arrow {
      transform: rotate(180deg);
    }
    /* CTA */
    .cta-block {
      background: linear-gradient(135deg, #1A2A3A, #0F1F2E);
      color: white;
      text-align: center;
      padding: 80px 0;
    }
    .shimmer-btn {
      position: relative;
      overflow: hidden;
    }
    .shimmer-btn::after {
      content: '';
      position: absolute;
      top: 0;
      left: -75%;
      width: 50%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255,255,255,0.25), transparent);
      transform: skewX(-20deg);
      transition: 0.7s;
    }
    .shimmer-btn:hover::after {
      left: 125%;
    }
    /* 页脚 */
    .footer {
      background: var(--deep-blue);
      color: #B0B8C1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #B0B8C1;
    }
    .footer a:hover {
      color: var(--amber-gold);
    }
    .social-icons i {
      font-size: 20px;
      margin-right: 16px;
      transition: 0.2s;
    }
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .hamburger { display: flex; }
      .nav-links {
        position: fixed;
        top: 72px;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: white;
        flex-direction: column;
        padding: 40px 24px;
        gap: 24px;
        box-shadow: -8px 0 24px rgba(0,0,0,0.08);
        transition: right 0.3s;
      }
      .nav-links.active { right: 0; }
      .hero .container { flex-direction: column; }
      .hero-text h1 { font-size: 36px; }
      .services-grid { grid-template-columns: 1fr; }
      .cases-grid { grid-template-columns: 1fr; }
      .solution-row, .solution-row.reverse { flex-direction: column; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .section-title { font-size: 28px; }
    }