/* roulang page: index */
:root {
      --primary: #E6004C;
      --primary-hover: #CC0040;
      --primary-soft: rgba(230, 0, 76, 0.08);
      --accent: #FFB800;
      --dark-bg: #1A1A2E;
      --gray-bg: #F9F9FB;
      --card-bg: #FFFFFF;
      --text-main: #1f1f2e;
      --text-body: #444;
      --text-weak: #777;
      --shadow-sm: 0 8px 30px rgba(230, 0, 76, 0.06);
      --shadow-hover: 0 12px 40px rgba(230, 0, 76, 0.12);
      --radius-card: 16px;
      --radius-pill: 50px;
      --radius-input: 12px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'Inter', system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
      margin: 0;
      background-color: var(--gray-bg);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
    }

    h1, h2, h3, .font-heading {
      font-weight: 700;
      color: var(--text-main);
      line-height: 1.3;
    }

    .container-nav, .container-section {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    #nav {
      background: rgba(26, 26, 46, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      position: fixed;
      top: 0;
      width: 100%;
      z-index: 50;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .nav-desktop {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 0.75rem;
      font-weight: 700;
      font-size: 1.6rem;
      letter-spacing: -0.3px;
      color: #fff;
      text-decoration: none;
    }

    .logo-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 40px;
      height: 40px;
      background: var(--primary);
      border-radius: 10px;
      font-size: 1.5rem;
      font-weight: 700;
      color: #fff;
      text-transform: uppercase;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-link {
      color: rgba(255, 255, 255, 0.85);
      text-decoration: none;
      font-weight: 500;
      font-size: 0.975rem;
      transition: all 0.2s;
      padding: 0.25rem 0;
    }

    .nav-link:hover {
      color: var(--primary);
    }

    .cta-btn {
      background-color: var(--primary);
      color: #fff;
      padding: 0.6rem 1.8rem;
      border-radius: var(--radius-pill);
      font-weight: 600;
      font-size: 0.95rem;
      text-decoration: none;
      display: inline-block;
      transition: all 0.25s;
      box-shadow: 0 4px 10px rgba(230, 0, 76, 0.4);
      border: none;
      cursor: pointer;
    }

    .cta-btn:hover {
      background-color: var(--primary-hover);
      box-shadow: 0 10px 20px rgba(230, 0, 76, 0.55);
      transform: translateY(-2px);
    }

    .mobile-nav {
      display: none;
      position: fixed;
      bottom: 16px;
      left: 16px;
      right: 16px;
      background: rgba(26, 26, 46, 0.95);
      backdrop-filter: blur(20px);
      border-radius: 40px;
      padding: 0.5rem 1.2rem;
      z-index: 60;
      box-shadow: 0 20px 35px rgba(0,0,0,0.3);
    }

    .mobile-nav-links {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      font-size: 0.7rem;
      font-weight: 500;
    }

    .mobile-cta-wrapper {
      background: var(--primary);
      border-radius: 50%;
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-top: -25px;
      box-shadow: 0 8px 20px rgba(230,0,76,0.7);
    }

    section {
      scroll-margin-top: 90px;
      padding: 5rem 0;
    }

    .section-title {
      font-size: 2.25rem;
      margin-bottom: 0.75rem;
    }

    .text-accent {
      color: var(--primary);
    }

    .btn-outline-light {
      border: 2px solid rgba(255,255,255,0.8);
      background: transparent;
      color: #fff;
      padding: 0.6rem 2rem;
      border-radius: var(--radius-pill);
      font-weight: 600;
      transition: 0.2s;
      white-space: nowrap;
      text-decoration: none;
      display: inline-block;
    }

    .btn-outline-light:hover {
      background: rgba(255,255,255,0.15);
    }

    .hero-bg {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }

    .overlay-gradient {
      background: radial-gradient(circle at 70% 30%, rgba(230,0,76,0.3) 0%, rgba(26,26,46,0.75) 80%);
      position: absolute;
      inset: 0;
    }

    .solution-card {
      transition: 0.25s ease;
      cursor: pointer;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      padding: 2rem;
      display: flex;
      align-items: flex-start;
      gap: 1.5rem;
      border-left: 5px solid transparent;
    }

    .solution-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-left-color: var(--primary);
    }

    .faq-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 28px 0;
      cursor: pointer;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.1rem;
      color: var(--text-main);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
      font-size: 0.95rem;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 1rem;
    }

    .stats-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.2;
    }

    input:focus, textarea:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(230,0,76,0.1);
    }

    @media (max-width: 768px) {
      .nav-desktop {
        display: none;
      }
      .mobile-nav {
        display: block;
      }
      section {
        padding: 3.5rem 0;
      }
      .section-title {
        font-size: 1.8rem !important;
      }
      .solution-card {
        flex-direction: column;
        gap: 1rem;
      }
    }

    @media (min-width: 769px) {
      .mobile-nav {
        display: none;
      }
    }