/* roulang page: index */
:root {
      /* 品牌色系 */
      --deep-space: #1B2A4A;
      --warm-gold: #D4A843;
      --bg-page: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-advantage: #EDF2F7;
      --text-title: #1B2A4A;
      --text-body: #4A5568;
      --text-muted: #718096;
      --text-light: #CBD5E0;
      --border-light: #E2E8F0;
      --footer-dark: #0F172A;
      
      /* Bootstrap 覆盖变量 */
      --bs-primary: #1B2A4A;
      --bs-body-bg: #F8FAFC;
      --bs-border-radius: 12px;
      --bs-btn-border-radius: 8px;
      --bs-btn-padding-x: 1.5rem;
      --bs-btn-padding-y: 0.6rem;
      --bs-card-border-radius: 12px;
      --bs-card-box-shadow: 0 4px 12px rgba(0,0,0,0.04);
      
      /* 间距 */
      --section-padding: 5rem 0;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.6;
      font-size: 16px;
      margin: 0;
      padding: 0;
    }
    
    h1, h2, h3, h4, h5, h6 {
      color: var(--text-title);
      font-weight: 700;
      letter-spacing: -0.02em;
    }
    
    h1 { font-size: 48px; }
    h2 { font-size: 31px; }
    h3 { font-size: 25px; }
    h4 { font-size: 20px; }
    
    @media (max-width: 768px) {
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      h3 { font-size: 22px; }
      h4 { font-size: 18px; }
    }
    
    a {
      color: var(--deep-space);
      text-decoration: none;
      transition: color 0.2s;
    }
    a:hover {
      color: var(--warm-gold);
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    button, input, textarea {
      font-family: inherit;
    }
    
    /* 容器自定义 */
    .container-lg {
      max-width: 1140px;
      margin: 0 auto;
      padding: 0 15px;
    }
    
    /* 顶部信息条 */
    .top-bar {
      background-color: var(--deep-space);
      color: var(--text-light);
      font-size: 13px;
      height: 36px;
      line-height: 36px;
      padding: 0;
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: relative;
      z-index: 1030;
    }
    .top-bar .container-lg {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .top-bar a {
      color: var(--text-light);
      text-decoration: none;
      margin-left: 20px;
      transition: color 0.2s;
    }
    .top-bar a:hover {
      color: var(--warm-gold);
    }
    
    /* 主导航 */
    .main-nav {
      height: 64px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      box-shadow: 0 1px 4px rgba(0,0,0,0.04);
      position: sticky;
      top: 0;
      z-index: 1020;
      display: flex;
      align-items: center;
      transition: all 0.3s;
    }
    .main-nav .container-lg {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo-area {
      display: flex;
      align-items: center;
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--deep-space);
    }
    .logo-area i {
      color: var(--warm-gold);
      font-size: 0.6rem;
      margin-left: 4px;
      transform: translateY(-2px);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 24px;
      list-style: none;
      margin: 0;
      padding: 0;
    }
    .nav-menu a {
      color: var(--text-body);
      font-weight: 500;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--deep-space);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--warm-gold);
      transition: width 0.25s ease;
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }
    
    /* 汉堡菜单 */
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--deep-space);
      cursor: pointer;
    }
    
    /* Hero */
    .hero-section {
      min-height: 85vh;
      background: linear-gradient(135deg, #0F172A 0%, #1B2A4A 50%, #2D1B3A 100%);
      position: relative;
      overflow: hidden;
      display: flex;
      align-items: center;
      color: white;
      padding: 2rem 0;
    }
    /* 星点粒子效果 (CSS only) */
    .hero-section::before {
      content: '';
      position: absolute;
      width: 4px;
      height: 4px;
      background: rgba(255,255,255,0.6);
      border-radius: 50%;
      box-shadow: 
        20px 30px 0 rgba(255,255,255,0.4), 80px 120px 0 rgba(255,255,255,0.3), 150px 50px 0 rgba(255,255,255,0.5),
        300px 200px 0 rgba(255,255,255,0.2), 500px 80px 0 rgba(255,255,255,0.4), 700px 300px 0 rgba(255,255,255,0.3),
        850px 120px 0 rgba(255,255,255,0.5), 1000px 250px 0 rgba(255,255,255,0.2), 150px 400px 0 rgba(255,255,255,0.3),
        400px 350px 0 rgba(255,255,255,0.4), 650px 450px 0 rgba(255,255,255,0.2), 900px 400px 0 rgba(255,255,255,0.5),
        1100px 150px 0 rgba(255,255,255,0.3);
      animation: twinkle 3s infinite alternate;
    }
    @keyframes twinkle {
      0% { opacity: 0.4; }
      100% { opacity: 0.9; }
    }
    .hero-content {
      position: relative;
      z-index: 10;
    }
    .hero-title {
      font-size: 48px;
      font-weight: 700;
      letter-spacing: 0.04em;
      color: white;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 2rem;
    }
    .btn-outline-light-custom {
      border: 2px solid white;
      color: white;
      background: transparent;
      padding: 0.7rem 2rem;
      border-radius: 8px;
      font-weight: 600;
      transition: all 0.25s;
    }
    .btn-outline-light-custom:hover {
      background: rgba(255,255,255,0.1);
      color: white;
    }
    .btn-warm-gold {
      background: var(--warm-gold);
      border: none;
      color: var(--deep-space);
      font-weight: 700;
      padding: 0.7rem 2rem;
      border-radius: 8px;
      transition: all 0.25s;
    }
    .btn-warm-gold:hover {
      filter: brightness(1.1);
      color: var(--deep-space);
    }
    
    /* 板块通用 */
    .section-padding {
      padding: var(--section-padding);
    }
    .section-title {
      margin-bottom: 3rem;
      text-align: center;
    }
    
    /* 服务卡片 */
    .service-card {
      background: var(--bg-card);
      border-radius: 12px;
      padding: 2rem;
      box-shadow: 0 4px 12px rgba(0,0,0,0.04);
      transition: all 0.25s ease;
      height: 100%;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: 0 8px 24px rgba(0,0,0,0.08);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      margin-bottom: 1.2rem;
      background: #EDF2F7;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }
    .service-icon img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    
    /* 优势数据 */
    .advantage-bg {
      background-color: var(--bg-advantage);
    }
    .big-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--warm-gold);
      line-height: 1.1;
    }
    .divider-gold {
      width: 30px;
      height: 2px;
      background: var(--warm-gold);
      margin: 0.8rem 0;
    }
    
    /* 案例卡片 */
    .case-card {
      background: white;
      border-radius: 12px;
      overflow: hidden;
      box-shadow: 0 4px 12px rgba(0,0,0,0.04);
      transition: 0.25s ease;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 12px 28px rgba(0,0,0,0.1);
    }
    .case-img {
      height: 200px;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.3s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.02);
    }
    
    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: #F8FAFC;
      color: var(--deep-space);
      font-weight: 700;
    }
    .accordion-button:focus {
      box-shadow: none;
      border-color: var(--border-light);
    }
    
    /* 联系表单 */
    .form-control {
      border-radius: 8px;
      border: 1px solid var(--border-light);
      padding: 0.7rem 1rem;
    }
    .form-control:focus {
      border-color: var(--deep-space);
      box-shadow: 0 0 0 0.2rem rgba(27,42,74,0.15);
    }
    
    /* 页脚 */
    .footer-dark {
      background: var(--deep-space);
      color: var(--text-light);
      padding: 3rem 0 1rem;
    }
    .footer-dark a {
      color: var(--text-light);
      text-decoration: none;
    }
    .footer-dark a:hover {
      color: var(--warm-gold);
    }
    .copyright-bar {
      background: var(--footer-dark);
      color: #A0AEC0;
      font-size: 0.9rem;
      padding: 1rem 0;
      margin-top: 2rem;
    }
    
    /* 响应式 */
    @media (max-width: 768px) {
      .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: white;
        padding: 1.5rem;
        box-shadow: 0 8px 20px rgba(0,0,0,0.1);
        gap: 16px;
      }
      .nav-menu.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .hero-title {
        font-size: 32px;
      }
      .top-bar .container-lg {
        flex-direction: column;
        align-items: flex-start;
      }
    }