/* roulang page: index */
:root {
      --bg-deep: #0A0E27;
      --cyan: #00F0FF;
      --amber: #FFB800;
      --white-soft: #F0F4FF;
      --gray-mid: #8E9CB2;
      --gray-light: #B0BED0;
      --card-bg: rgba(255,255,255,0.03);
      --card-border: rgba(0,240,255,0.15);
      --card-hover-border: rgba(0,240,255,0.5);
      --glass-bg: rgba(10,14,39,0.65);
      --font-head: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      --radius-card: 20px;
      --radius-btn: 40px;
      --shadow-card: 0 15px 35px rgba(0,0,0,0.55);
      --spacing-section: 100px;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg-deep);
      color: #E0E8F5;
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-head);
      font-weight: 600;
      letter-spacing: -0.02em;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.2s ease, border-color 0.2s ease;
    }

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 40;
      background: rgba(10,14,39,0.7);
      backdrop-filter: blur(18px);
      -webkit-backdrop-filter: blur(18px);
      border-bottom: 1px solid rgba(0,240,255,0.1);
      transition: background 0.25s ease;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 75px;
    }
    .logo {
      font-family: var(--font-head);
      font-size: 1.9rem;
      font-weight: 700;
      color: white;
      letter-spacing: 1px;
      background: linear-gradient(135deg, #fff 0%, #00F0FF 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 2.2rem;
    }
    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: #ccd6f0;
      padding: 0.4rem 0;
      border-bottom: 2px solid transparent;
      transition: 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: white;
      border-bottom-color: var(--cyan);
    }
    .btn-nav {
      background: var(--amber);
      color: #0A0E27 !important;
      font-weight: 700;
      padding: 0.6rem 1.8rem !important;
      border-radius: 30px;
      border: none;
      font-size: 0.9rem;
      letter-spacing: 0.3px;
      transition: all 0.25s;
      box-shadow: 0 4px 14px rgba(255,184,0,0.3);
    }
    .btn-nav:hover {
      background: #ffc940;
      box-shadow: 0 0 20px rgba(255,184,0,0.7);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: white;
      cursor: pointer;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }

    /* Hero */
    .hero {
      padding: 140px 0 90px;
      position: relative;
      background: radial-gradient(circle at 20% 30%, rgba(0,240,255,0.08) 0%, #0A0E27 70%);
      overflow: hidden;
    }
    .hero-bg-img {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.25;
      z-index: 0;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3.5rem;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 1.1;
    }
    .hero-right {
      flex: 0.9;
      display: flex;
      justify-content: center;
    }
    .hero-tag {
      color: var(--cyan);
      font-weight: 500;
      font-size: 1.2rem;
      letter-spacing: 1px;
      margin-bottom: 1.2rem;
    }
    .hero h1 {
      font-size: 3.3rem;
      font-weight: 700;
      line-height: 1.2;
      color: white;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.15rem;
      color: #b9c7e0;
      margin-bottom: 2.5rem;
    }
    .btn-group {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: linear-gradient(135deg, #FFB800, #FFA000);
      color: #0A0E27;
      font-weight: 700;
      padding: 0.9rem 2.5rem;
      border-radius: 30px;
      font-size: 1rem;
      border: none;
      transition: 0.25s;
      box-shadow: 0 6px 18px rgba(255,184,0,0.45);
      display: inline-block;
    }
    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(255,184,0,0.8);
      transform: translateY(-2px);
      background: #ffc526;
    }
    .btn-ghost {
      border: 1px solid var(--cyan);
      color: var(--cyan);
      background: transparent;
      padding: 0.9rem 2.3rem;
      border-radius: 30px;
      font-weight: 600;
      transition: 0.25s;
    }
    .btn-ghost:hover {
      background: rgba(0,240,255,0.12);
      border-color: #99f6ff;
    }
    .hero-image-card {
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(18px);
      border-radius: 28px;
      border: 1px solid rgba(0,240,255,0.25);
      padding: 12px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
    }
    .hero-image-card img {
      border-radius: 20px;
      width: 100%;
    }

    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero h1 {
        font-size: 2.5rem;
      }
      .hero-right {
        order: -1;
      }
    }

    /* 信任条 */
    .trust-bar {
      border-top: 1px solid rgba(255,255,255,0.08);
      border-bottom: 1px solid rgba(255,255,255,0.08);
      padding: 24px 0;
      display: flex;
      justify-content: center;
      gap: 3rem;
      flex-wrap: wrap;
      color: #9aa9c1;
      font-size: 0.9rem;
      font-weight: 500;
    }

    section {
      padding: var(--spacing-section) 0;
    }

    .section-title {
      font-size: 2.3rem;
      font-weight: 600;
      color: white;
      margin-bottom: 1rem;
      text-align: center;
    }
    .section-sub {
      color: #a4b4cc;
      text-align: center;
      max-width: 650px;
      margin: 0 auto 3.5rem;
    }

    /* 痛点卡片 */
    .pain-grid {
      display: flex;
      gap: 2rem;
      flex-wrap: wrap;
    }
    .pain-card {
      flex: 1 1 280px;
      background: rgba(20,25,45,0.7);
      backdrop-filter: blur(14px);
      border: 1px solid rgba(0,240,255,0.12);
      border-radius: 24px;
      padding: 2rem;
      transition: 0.25s;
    }
    .pain-card:hover {
      border-color: rgba(0,240,255,0.4);
      background: rgba(30,35,55,0.8);
    }
    .pain-icon {
      font-size: 2.2rem;
      color: var(--cyan);
      margin-bottom: 1.3rem;
    }

    /* 解决方案玻璃卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 2rem;
    }
    .glass-card {
      background: rgba(255,255,255,0.02);
      backdrop-filter: blur(22px);
      border: 1px solid var(--card-border);
      border-radius: 24px;
      padding: 2.4rem 1.8rem;
      transition: all 0.3s;
    }
    .glass-card:hover {
      border-color: var(--card-hover-border);
      box-shadow: 0 0 28px rgba(0,240,255,0.2);
      transform: translateY(-5px);
    }
    .card-icon {
      font-size: 2.8rem;
      color: var(--cyan);
      margin-bottom: 1.2rem;
    }
    .glass-card h3 {
      font-size: 1.5rem;
      margin-bottom: 0.8rem;
    }
    .link-arrow {
      color: var(--cyan);
      font-weight: 600;
      margin-top: 1.2rem;
      display: inline-block;
    }

    /* 数据看板 */
    .stats-grid {
      display: flex;
      justify-content: center;
      gap: 3rem;
      flex-wrap: wrap;
      text-align: center;
    }
    .stat-item h3 {
      font-size: 3.4rem;
      font-weight: 700;
      color: var(--amber);
    }

    /* 证言 */
    .testimonial-grid {
      display: flex;
      gap: 2rem;
      flex-wrap: wrap;
    }
    .testimonial-card {
      flex: 1 1 300px;
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(16px);
      border-radius: 24px;
      padding: 2rem;
      display: flex;
      gap: 1.3rem;
      border: 1px solid rgba(0,240,255,0.1);
    }
    .avatar {
      width: 56px;
      height: 56px;
      border-radius: 50%;
      background: url('/assets/images/backpic/back-2.webp') center/cover;
      flex-shrink: 0;
    }

    /* FAQ */
    .accordion-faq .accordion-item {
      background: rgba(20,25,45,0.6);
      border: 1px solid rgba(0,240,255,0.12);
      border-radius: 18px;
      margin-bottom: 1rem;
    }
    .accordion-title {
      font-size: 1.1rem;
      font-weight: 600;
      color: white;
      padding: 1.2rem 1.8rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .accordion-content {
      padding: 0 1.8rem 1.4rem;
      color: #ccd7ec;
    }

    /* CTA */
    .cta-dark {
      background: #060B1F;
      border-radius: 32px;
      padding: 3.5rem 2rem;
      text-align: center;
      border: 1px solid rgba(0,240,255,0.2);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 2rem;
      color: #b0bed0;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }