/* roulang page: index */
:root {
      --deep-blue: #0A0F24;
      --electric-cyan: #00E5FF;
      --amber-orange: #FF6B35;
      --glass-bg: rgba(255, 255, 255, 0.04);
      --glass-border: rgba(255, 255, 255, 0.08);
      --text-body: rgba(255, 255, 255, 0.75);
      --text-heading: rgba(255, 255, 255, 0.95);
      --text-muted: rgba(255, 255, 255, 0.45);
      --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
      --cyan-glow: 0 0 24px rgba(0, 229, 255, 0.5);
      --border-radius-card: 16px;
      --border-radius-btn: 12px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif;
      --font-number: "DIN Alternate", "Oswald", "Inter", sans-serif;
      --section-gap: 120px;
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--deep-blue);
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--deep-blue);
      color: var(--text-body);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s ease;
    }

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

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      padding: 16px 0;
      transition: background 0.3s ease, backdrop-filter 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
    }

    .site-header.scrolled {
      background: rgba(10, 15, 36, 0.85);
      backdrop-filter: blur(24px);
      -webkit-backdrop-filter: blur(24px);
      box-shadow: 0 1px 0 rgba(255, 255, 255, 0.06);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: #fff;
      letter-spacing: -0.3px;
    }
    .logo-icon {
      font-size: 1.8rem;
      color: var(--electric-cyan);
      filter: drop-shadow(0 0 8px rgba(0,229,255,0.6));
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-body);
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--electric-cyan);
      border-bottom-color: var(--electric-cyan);
    }

    .btn-nav {
      background: transparent;
      border: 1px solid var(--electric-cyan);
      color: var(--electric-cyan);
      padding: 10px 22px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.3s ease;
    }
    .btn-nav:hover {
      background: rgba(0,229,255,0.12);
      box-shadow: 0 0 18px rgba(0,229,255,0.4);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      display: block;
      width: 26px;
      height: 2px;
      background: #fff;
      transition: 0.2s;
    }
    .mobile-menu {
      display: none;
    }

    /* 按钮系统 */
    .btn-primary {
      background: linear-gradient(135deg, #00E5FF, #FF6B35);
      color: #000;
      font-weight: 700;
      padding: 16px 40px;
      border-radius: var(--border-radius-btn);
      border: none;
      cursor: pointer;
      box-shadow: 0 0 24px rgba(0, 229, 255, 0.5);
      transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      display: inline-block;
      text-align: center;
      font-size: 1rem;
    }
    .btn-primary:hover {
      box-shadow: 0 0 40px rgba(0, 229, 255, 0.8);
      transform: scale(1.04);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--electric-cyan);
      color: var(--electric-cyan);
      padding: 14px 38px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      transition: 0.3s;
      display: inline-block;
    }
    .btn-secondary:hover {
      background: rgba(0, 229, 255, 0.1);
      box-shadow: 0 0 18px rgba(0,229,255,0.5);
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      padding: 120px 0 80px;
      background: radial-gradient(circle at 30% 40%, rgba(0,229,255,0.18) 0%, rgba(10,15,36,1) 70%);
    }
    .hero-content {
      display: flex;
      gap: 48px;
      align-items: center;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 55%;
    }
    .hero h1 {
      font-size: clamp(2.2rem, 5vw, 3.5rem);
      font-weight: 800;
      color: var(--text-heading);
      line-height: 1.15;
      letter-spacing: -0.02em;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 1.1rem;
      color: var(--text-body);
      max-width: 540px;
      margin-bottom: 36px;
    }
    .hero-visual {
      flex: 1 1 40%;
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      backdrop-filter: blur(8px);
    }
    .hero-visual img {
      border-radius: 20px;
      opacity: 0.85;
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    /* 板块通用 */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-desc {
      color: var(--text-muted);
      text-align: center;
      max-width: 680px;
      margin: 0 auto 48px;
      font-size: 1.1rem;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
    }
    .glass-card {
      background: rgba(255,255,255,0.04);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: var(--border-radius-card);
      padding: 32px 24px;
      box-shadow: var(--card-shadow);
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      border-color: var(--electric-cyan);
      background: rgba(255,255,255,0.06);
      box-shadow: 0 16px 48px rgba(0,229,255,0.15);
    }
    .icon-cyan {
      font-size: 2rem;
      color: var(--electric-cyan);
      margin-bottom: 20px;
    }

    /* 解决方案矩阵 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 24px;
    }
    .solution-card {
      background: rgba(255,255,255,0.04);
      backdrop-filter: blur(18px);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: 16px;
      overflow: hidden;
      transition: 0.3s;
    }
    .solution-card:hover {
      border-color: var(--electric-cyan);
    }
    .solution-img {
      height: 180px;
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .solution-content {
      padding: 20px;
    }

    /* 数据区 */
    .results-bg {
      background: #060B1C;
    }
    .stats-grid {
      display: flex;
      justify-content: center;
      flex-wrap: wrap;
      gap: 48px;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--electric-cyan);
    }
    .stat-label {
      font-size: 0.9rem;
      letter-spacing: 0.08em;
      text-transform: uppercase;
      color: var(--text-muted);
    }

    /* 证言横向滚动 */
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 20px;
      scroll-snap-type: x mandatory;
    }
    .testimonial-card {
      flex: 0 0 380px;
      scroll-snap-align: start;
      background: var(--glass-bg);
      backdrop-filter: blur(18px);
      border-radius: 16px;
      padding: 28px;
      border: 1px solid var(--glass-border);
    }
    .quote-mark {
      font-size: 3rem;
      color: var(--electric-cyan);
      line-height: 1;
    }

    /* FAQ */
    .faq-item {
      background: rgba(255,255,255,0.03);
      border-radius: 12px;
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      padding: 0 20px;
      color: var(--text-body);
    }

    /* CTA */
    .cta-band {
      background: #060B1C;
      text-align: center;
      padding: 80px 0;
    }

    /* Footer */
    .footer {
      background: #040812;
      padding: 60px 0 30px;
      color: var(--text-muted);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 36px;
    }

    @media (max-width: 1024px) {
      .footer-grid { grid-template-columns: repeat(2,1fr); }
      .hero-content { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .mobile-menu.active { display: flex; flex-direction: column; background: rgba(10,15,36,0.96); position: fixed; top: 70px; left:0; width:100%; padding:32px; }
      .footer-grid { grid-template-columns: 1fr; }
      .stats-grid { gap: 28px; }
    }