/* roulang page: index */
:root {
      --primary-xuan: #1A2B3C;
      --accent-gold: #C59B3C;
      --accent-gold-deep: #A8812E;
      --bg-light: #F8F9FA;
      --white: #FFFFFF;
      --text-body: #4A5568;
      --text-muted: #718096;
      --border-light: rgba(0,0,0,0.04);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(26,43,60,0.1);
      --radius-card: 16px;
      --radius-btn: 8px;
      --font-cn: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-en: "Inter", "SF Pro Display", sans-serif;
      --transition-smooth: all 0.25s ease;
      --container-max: 1200px;
      --nav-height: 80px;
    }

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

    body {
      font-family: var(--font-cn);
      background: var(--bg-light);
      color: var(--text-body);
      line-height: 1.8;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, .nav-logo, .cta-text strong {
      font-family: var(--font-cn);
      font-weight: 700;
    }

    .en-font, .stat-number, .btn, .tag {
      font-family: var(--font-en);
    }

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

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

    button, .btn {
      cursor: pointer;
      border: none;
      background: none;
      font-family: inherit;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
      width: 100%;
    }

    /* 导航系统 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: var(--nav-height);
      display: flex;
      align-items: center;
      transition: background 0.3s ease, backdrop-filter 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
    }

    .site-header.scrolled {
      background: rgba(26, 43, 60, 0.85);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }

    .logo {
      font-size: 28px;
      font-weight: 800;
      color: var(--accent-gold);
      letter-spacing: 2px;
      font-family: var(--font-cn);
      transition: color 0.3s;
    }
    .site-header.scrolled .logo {
      color: var(--accent-gold);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-link {
      font-weight: 500;
      color: var(--white);
      font-size: 15px;
      position: relative;
      padding: 6px 0;
    }
    .site-header.scrolled .nav-link {
      color: #E2E8F0;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-gold);
      transition: width 0.3s;
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    .nav-link:hover {
      color: var(--accent-gold);
    }

    .btn-primary {
      background: var(--accent-gold);
      color: #FFF;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      font-size: 15px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition-smooth);
      border: none;
      letter-spacing: 0.5px;
      box-shadow: 0 4px 12px rgba(197,155,60,0.3);
      white-space: nowrap;
    }
    .btn-primary:hover {
      background: var(--accent-gold-deep);
      transform: translateY(-1px);
      box-shadow: 0 8px 18px rgba(197,155,60,0.4);
    }

    .btn-ghost {
      background: transparent;
      color: #FFF;
      border: 1px solid rgba(255,255,255,0.5);
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      transition: var(--transition-smooth);
    }
    .btn-ghost:hover {
      background: #FFF;
      color: var(--primary-xuan);
      border-color: #FFF;
    }

    .btn-outline {
      background: transparent;
      color: var(--primary-xuan);
      border: 2px solid var(--primary-xuan);
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      transition: var(--transition-smooth);
    }
    .btn-outline:hover {
      background: var(--primary-xuan);
      color: #FFF;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--accent-gold);
      transition: 0.3s;
    }

    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background: var(--primary-xuan);
        flex-direction: column;
        justify-content: center;
        gap: 40px;
        transition: right 0.4s ease;
        backdrop-filter: blur(20px);
      }
      .nav-menu.open {
        right: 0;
      }
      .nav-link {
        font-size: 20px;
        color: #FFF;
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
      .btn-primary.nav-cta {
        display: none;
      }
      .mobile-cta {
        display: block;
      }
    }
    @media (min-width: 769px) {
      .mobile-cta {
        display: none;
      }
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      background: radial-gradient(circle at 30% 30%, #1F3A4B, var(--primary-xuan));
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding-top: var(--nav-height);
    }
    .hero-bg-svg {
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      opacity: 0.15;
      background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 600"><circle cx="200" cy="200" r="120" fill="none" stroke="%23C59B3C" stroke-width="2"/><circle cx="260" cy="280" r="80" fill="none" stroke="%23C59B3C" stroke-width="1.5"/><path d="M100 350 Q200 250 300 400" stroke="%23C59B3C" stroke-width="2" fill="none"/></svg>') no-repeat center/contain;
    }
    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      max-width: 600px;
    }
    .hero h1 {
      font-size: 52px;
      font-weight: 800;
      color: #FFF;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 20px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
      font-weight: 400;
    }
    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      color: rgba(255,255,255,0.7);
      font-size: 24px;
      animation: bounce 2s infinite;
    }
    @keyframes bounce {
      0%,20%,50%,80%,100%{transform:translateX(-50%) translateY(0);}
      40%{transform:translateX(-50%) translateY(-8px);}
    }

    @media (max-width: 768px) {
      .hero h1 { font-size: 36px; }
      .hero-content { flex-direction: column; text-align: center; }
      .hero-bg-svg { display: none; }
    }

    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary-xuan);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 48px;
    }

    /* 优势网格 2x3 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .adv-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-light);
      transition: var(--transition-smooth);
    }
    .adv-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .adv-icon {
      font-size: 32px;
      color: var(--accent-gold);
      margin-bottom: 20px;
    }
    .adv-title {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-xuan);
      margin-bottom: 12px;
    }

    /* 数据徽章 */
    .stats-row {
      display: flex;
      justify-content: space-around;
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 40px 20px;
      box-shadow: var(--shadow-card);
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--accent-gold);
    }
    .stat-label {
      color: var(--primary-xuan);
      font-weight: 600;
      margin-top: 8px;
    }

    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      height: 240px;
      object-fit: cover;
      width: 100%;
    }
    .case-body {
      padding: 24px;
    }
    .tag {
      background: rgba(197,155,60,0.1);
      color: var(--accent-gold);
      border-radius: 20px;
      padding: 4px 12px;
      font-size: 13px;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 12px;
    }

    /* 服务方案交替 */
    .service-block {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .service-left {
      flex: 1;
      border-left: 2px solid var(--accent-gold);
      padding-left: 30px;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 28px;
      margin-bottom: 24px;
      box-shadow: var(--shadow-card);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid #E2E8F0;
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 700;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
    }

    /* CTA横幅 */
    .cta-band {
      background: var(--primary-xuan);
      color: #FFF;
      text-align: center;
      border-radius: var(--radius-card);
      padding: 60px;
    }

    footer {
      background: var(--primary-xuan);
      color: #A0AEC0;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .advantages-grid, .cases-grid { grid-template-columns: 1fr; }
      .stats-row { flex-wrap: wrap; gap: 20px; }
      .footer-grid { grid-template-columns: 1fr; }
    }