/* roulang page: index */
:root {
      --primary-deep: #1B3A5C;
      --accent-warm: #F47B3E;
      --bg-light: #FAFBFD;
      --card-white: #FFFFFF;
      --text-main: #1E293B;
      --text-soft: #64748B;
      --text-title: #0F172A;
      --border-light: #E2E8F0;
      --success-green: #10B981;
      --warning-gray: #94A3B8;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 4px 12px rgba(0,0,0,0.08);
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.5;
      margin: 0;
      padding: 0;
    }
    h1, h2, h3, h4 {
      color: var(--text-title);
      margin-bottom: 0.5rem;
    }
    a {
      text-decoration: none;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container {
      max-width: 1140px;
      margin: 0 auto;
    }
    /* 导航栏 */
    .navbar-custom {
      background-color: rgba(255,255,255,0.92);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border-light);
      padding: 0.5rem 0;
      position: sticky;
      top: 0;
      z-index: 1020;
    }
    .navbar-brand-custom {
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .navbar-brand-custom img {
      width: 36px;
      height: 36px;
      object-fit: contain;
      border-radius: 6px;
    }
    .navbar-brand-custom span {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-deep);
      letter-spacing: -0.3px;
    }
    .nav-link-custom {
      color: var(--text-soft);
      font-size: 14px;
      margin-left: 32px;
      font-weight: 500;
      position: relative;
      padding: 0.25rem 0;
    }
    .nav-link-custom:hover,
    .nav-link-custom.active {
      color: var(--primary-deep);
    }
    .nav-link-custom.active::after {
      content: "";
      position: absolute;
      bottom: -4px;
      left: 50%;
      transform: translateX(-50%);
      width: 20px;
      height: 2px;
      background-color: var(--primary-deep);
      border-radius: 2px;
    }
    .offcanvas-body .nav-link-custom {
      margin-left: 0;
      padding: 12px 16px;
      border-bottom: 1px solid var(--border-light);
      font-size: 16px;
    }
    /* 按钮 */
    .btn-primary-custom {
      background-color: var(--primary-deep);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 500;
      font-size: 15px;
      border: none;
      transition: background-color 0.2s;
    }
    .btn-primary-custom:hover {
      background-color: #152E4A;
      color: white;
    }
    .btn-accent {
      background-color: var(--accent-warm);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 500;
      font-size: 15px;
      border: none;
      transition: background-color 0.2s;
    }
    .btn-accent:hover {
      background-color: #E0692C;
      color: white;
    }
    .btn-outline-custom {
      border: 1px solid var(--primary-deep);
      color: var(--primary-deep);
      background: transparent;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 500;
      font-size: 15px;
      transition: all 0.2s;
    }
    .btn-outline-custom:hover {
      background-color: var(--primary-deep);
      color: white;
    }
    /* 板块间距 */
    section {
      padding: 120px 0;
    }
    @media (max-width: 992px) {
      section {
        padding: 80px 0;
      }
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    .section-title {
      font-size: 24px;
      font-weight: 600;
      margin-bottom: 12px;
      position: relative;
      display: inline-block;
    }
    .section-title::before {
      content: "";
      display: inline-block;
      width: 4px;
      height: 20px;
      background-color: var(--primary-deep);
      margin-right: 12px;
      vertical-align: middle;
      border-radius: 2px;
    }
    .section-lead {
      color: var(--text-soft);
      font-size: 15px;
      margin-bottom: 40px;
    }
    /* 卡片 */
    .card-custom {
      background: var(--card-white);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      padding: 24px;
      transition: transform 0.2s, box-shadow 0.2s;
      border: none;
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-2px);
      box-shadow: var(--shadow-card-hover);
    }
    /* 指标卡片 */
    .metric-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 24px 16px;
      text-align: center;
      box-shadow: var(--shadow-card);
      border-bottom: 4px solid var(--accent-warm);
    }
    .metric-number {
      font-family: var(--font-number);
      font-size: 40px;
      font-weight: 700;
      color: var(--primary-deep);
      line-height: 1.2;
    }
    .metric-label {
      font-size: 13px;
      color: var(--text-soft);
    }
    .progress-custom {
      height: 4px;
      background-color: var(--border-light);
      border-radius: 2px;
      margin-top: 12px;
    }
    .progress-custom .progress-bar {
      background-color: var(--accent-warm);
      border-radius: 2px;
    }
    /* 对比区块 */
    .compare-before {
      background-color: #F8FAFC;
      border-radius: var(--radius-card);
      padding: 32px;
      color: var(--text-soft);
    }
    .compare-after {
      background-color: var(--card-white);
      border-left: 4px solid var(--success-green);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
    }
    .vs-divider {
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--text-soft);
      font-size: 18px;
    }
    /* FAQ 手风琴覆盖 */
    .accordion-button:not(.collapsed) {
      background-color: transparent;
      color: var(--primary-deep);
      box-shadow: none;
      font-weight: 600;
    }
    .accordion-button {
      font-weight: 600;
      color: var(--text-main);
      background-color: transparent;
      padding: 16px 20px;
      border-bottom: 1px solid var(--border-light);
    }
    .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-light);
      background: transparent;
    }
    .accordion-button:focus {
      box-shadow: none;
      border-color: var(--border-light);
    }
    .accordion-body {
      color: #475569;
      padding: 16px 20px;
    }
    /* 表单 */
    .form-control-custom {
      border: 1px solid var(--border-light);
      border-radius: var(--radius-input);
      padding: 12px 16px;
      font-size: 15px;
      transition: border-color 0.2s, box-shadow 0.2s;
    }
    .form-control-custom:focus {
      border-color: var(--primary-deep);
      box-shadow: 0 0 0 3px rgba(27,58,92,0.1);
      outline: none;
    }
    /* 页脚 */
    .footer-custom {
      background-color: var(--primary-deep);
      color: #CBD5E1;
      padding: 48px 0 24px;
    }
    .footer-custom a {
      color: #94A3B8;
      transition: color 0.2s;
    }
    .footer-custom a:hover {
      color: white;
    }
    .footer-brand {
      display: flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 12px;
    }
    .footer-brand img {
      width: 32px;
      height: 32px;
      object-fit: contain;
    }
    /* 响应式微调 */
    @media (max-width: 576px) {
      .metric-number {
        font-size: 32px;
      }
    }
    .hero-img {
      border-radius: 16px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.06);
      object-fit: cover;
      width: 100%;
      height: auto;
      max-height: 400px;
    }
    .service-icon {
      width: 48px;
      height: 48px;
      background-color: #F0F4FA;
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary-deep);
      font-size: 24px;
      margin-bottom: 16px;
    }