/* roulang page: index */
:root {
      --primary-deep: #0A1929;
      --primary-navy: #001F3F;
      --secondary-glow: #00E5A0;
      --secondary-hover: #00C78C;
      --accent-red: #FF4D4D;
      --bg-light: #F4F6F8;
      --bg-white: #FFFFFF;
      --text-dark: #0A1929;
      --text-body: #4A5568;
      --text-muted: #8892B0;
      --border-light: rgba(0, 229, 160, 0.15);
      --border-subtle: #E2E8F0;
      --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.04);
      --shadow-hover: 0 12px 30px rgba(0, 229, 160, 0.08);
      --border-radius: 8px;
      --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
      --sidebar-width: 240px;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-body);
      margin: 0;
      line-height: 1.7;
      display: flex;
      flex-direction: row;
      min-height: 100vh;
    }
    h1, h2, h3, h4, .h1, .h2, .h3 {
      font-weight: 700;
      color: var(--text-dark);
      letter-spacing: -0.02em;
    }
    a {
      text-decoration: none;
      transition: color 0.2s ease;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    /* 左侧竖向导航 */
    .sidebar-nav {
      width: var(--sidebar-width);
      background-color: var(--primary-deep);
      color: white;
      display: flex;
      flex-direction: column;
      position: fixed;
      top: 0;
      left: 0;
      bottom: 0;
      z-index: 1030;
      box-shadow: 2px 0 15px rgba(0,0,0,0.2);
      transition: transform 0.3s ease;
      padding: 1.8rem 1.2rem;
    }
    .brand-logo {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      margin-bottom: 2.5rem;
      font-size: 1.6rem;
      font-weight: 700;
      color: white;
      letter-spacing: -0.5px;
    }
    .brand-logo i {
      font-size: 2rem;
      color: var(--secondary-glow);
    }
    .nav-menu {
      display: flex;
      flex-direction: column;
      gap: 0.5rem;
      flex: 1;
    }
    .nav-link-item {
      color: var(--text-muted);
      padding: 0.7rem 1rem;
      border-radius: 6px;
      font-weight: 500;
      display: flex;
      align-items: center;
      gap: 0.8rem;
      transition: all 0.2s ease;
      border-left: 4px solid transparent;
    }
    .nav-link-item i {
      width: 20px;
      font-size: 1.1rem;
      text-align: center;
    }
    .nav-link-item:hover, .nav-link-item.active {
      color: white;
      background-color: rgba(0, 229, 160, 0.08);
      border-left-color: var(--secondary-glow);
    }
    .nav-link-item.active {
      color: var(--secondary-glow);
      font-weight: 600;
    }
    .sidebar-footer {
      margin-top: auto;
      font-size: 0.8rem;
      color: var(--text-muted);
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 1.2rem;
    }
    /* 主内容区域 */
    .main-content {
      margin-left: var(--sidebar-width);
      flex: 1;
      width: calc(100% - var(--sidebar-width));
      background-color: var(--bg-light);
    }
    section {
      padding: 5rem 0;
    }
    .section-title h2 {
      font-size: 2.5rem;
      font-weight: 700;
      margin-bottom: 0.8rem;
      position: relative;
      display: inline-block;
    }
    .section-title h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 60px;
      height: 4px;
      background-color: var(--secondary-glow);
      border-radius: 2px;
    }
    .btn-primary-custom {
      background-color: var(--secondary-glow);
      border: none;
      color: var(--primary-deep);
      font-weight: 600;
      padding: 0.75rem 2rem;
      border-radius: var(--border-radius);
      transition: all 0.25s ease;
      box-shadow: 0 4px 12px rgba(0, 229, 160, 0.25);
      display: inline-block;
    }
    .btn-primary-custom:hover {
      background-color: var(--secondary-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(0, 229, 160, 0.35);
      color: var(--primary-deep);
    }
    .btn-outline-custom {
      background: transparent;
      border: 2px solid var(--secondary-glow);
      color: var(--secondary-glow);
      font-weight: 600;
      padding: 0.75rem 2rem;
      border-radius: var(--border-radius);
      transition: all 0.25s ease;
    }
    .btn-outline-custom:hover {
      background-color: var(--secondary-glow);
      color: var(--primary-deep);
      transform: translateY(-2px);
    }
    .card-custom {
      background: var(--bg-white);
      border: 1px solid var(--border-light);
      border-radius: var(--border-radius);
      box-shadow: var(--shadow-card);
      transition: box-shadow 0.25s ease, transform 0.25s ease;
      height: 100%;
    }
    .card-custom:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-5px);
    }
    .accent-number {
      font-feature-settings: "tnum";
      font-weight: 700;
      color: var(--secondary-glow);
    }
    .hero-section {
      background: linear-gradient(135deg, var(--primary-deep) 0%, #001F3F 100%);
      min-height: 90vh;
      display: flex;
      align-items: center;
      color: white;
      position: relative;
      overflow: hidden;
    }
    .hero-bg-visual {
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.25;
      mask-image: linear-gradient(to left, rgba(0,0,0,0.7), transparent);
    }
    .faq-accordion .accordion-button {
      font-weight: 600;
      color: var(--text-dark);
      background-color: white;
      box-shadow: none;
      border-bottom: 1px solid var(--border-subtle);
      padding: 1.2rem 1.5rem;
    }
    .faq-accordion .accordion-button:not(.collapsed) {
      background-color: #F8FAFC;
      color: var(--primary-deep);
      box-shadow: none;
    }
    .faq-accordion .accordion-button::after {
      color: var(--secondary-glow);
    }
    .form-control-custom {
      border: none;
      border-bottom: 1px solid #CBD5E0;
      border-radius: 4px;
      padding: 0.75rem 0.5rem;
      background: transparent;
      transition: border 0.2s;
    }
    .form-control-custom:focus {
      border-bottom-color: var(--secondary-glow);
      box-shadow: 0 4px 10px rgba(0,229,160,0.1);
      outline: none;
    }
    /* 移动端响应式 */
    @media (max-width: 768px) {
      body {
        flex-direction: column;
      }
      .sidebar-nav {
        transform: translateX(-100%);
        width: 260px;
        position: fixed;
        height: 100%;
      }
      .sidebar-nav.mobile-show {
        transform: translateX(0);
      }
      .main-content {
        margin-left: 0;
        width: 100%;
      }
      .mobile-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        padding: 1rem 1.5rem;
        background: var(--primary-deep);
        color: white;
        position: sticky;
        top: 0;
        z-index: 1020;
      }
      .hero-bg-visual {
        width: 100%;
        opacity: 0.15;
      }
      section {
        padding: 3rem 0;
      }
      .section-title h2 {
        font-size: 2rem;
      }
    }
    @media (min-width: 769px) {
      .mobile-header, .mobile-menu-toggle {
        display: none;
      }
    }