/* roulang page: index */
:root {
      --deep-space: #0A0E17;
      --aurora-cyan: #00F0FF;
      --deep-blue: #101826;
      --warm-gold: #D4AF37;
      --text-white: #FFFFFF;
      --text-steel: #B0C4DE;
      --text-muted: #6B7B8D;
      --border-glow: rgba(0, 240, 255, 0.15);
      --card-bg: rgba(16, 24, 38, 0.7);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-pill: 50px;
      --shadow-glow: 0 20px 40px rgba(0, 240, 255, 0.1);
      --transition-smooth: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-mono: 'DIN Alternate', 'Inter', sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--deep-space);
      color: var(--text-steel);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      background: none;
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.05em;
      white-space: nowrap;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 80px;
      display: flex;
      align-items: center;
      padding: 0 60px;
      background: rgba(10, 14, 23, 0.6);
      backdrop-filter: blur(16px);
      transition: var(--transition-smooth);
      border-bottom: 1px solid transparent;
    }

    .header.scrolled {
      background: rgba(10, 14, 23, 0.92);
      backdrop-filter: blur(30px);
      border-bottom: 1px solid var(--border-glow);
      box-shadow: 0 8px 32px rgba(0,0,0,0.4);
    }

    .logo {
      font-size: 28px;
      font-weight: 900;
      color: var(--text-white);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .logo .accent {
      color: var(--aurora-cyan);
      text-shadow: 0 0 12px rgba(0,240,255,0.6);
    }
    .logo .gold-dot {
      width: 8px;
      height: 8px;
      background: var(--warm-gold);
      border-radius: 50%;
      margin-left: 2px;
      box-shadow: 0 0 10px var(--warm-gold);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 36px;
      margin-left: auto;
    }

    .nav-link {
      color: var(--text-steel);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 8px 0;
    }

    .nav-link:hover,
    .nav-link.active {
      color: var(--text-white);
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--aurora-cyan);
      transition: width 0.3s ease;
      box-shadow: 0 0 8px var(--aurora-cyan);
    }

    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--aurora-cyan);
      color: var(--deep-space);
      border-radius: var(--radius-pill);
      padding: 12px 28px;
      font-weight: 700;
      box-shadow: 0 4px 20px rgba(0,240,255,0.3);
    }

    .btn-primary:hover {
      background: #33F5FF;
      box-shadow: 0 8px 30px rgba(0,240,255,0.55);
      transform: translateY(-2px);
    }

    .btn-outline {
      border: 1px solid var(--aurora-cyan);
      color: var(--aurora-cyan);
      border-radius: var(--radius-pill);
      padding: 12px 28px;
      background: transparent;
      font-weight: 600;
    }

    .btn-outline:hover {
      background: var(--aurora-cyan);
      color: var(--deep-space);
      box-shadow: 0 8px 25px rgba(0,240,255,0.4);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      margin-left: auto;
      z-index: 1001;
    }
    .hamburger span {
      width: 28px;
      height: 2px;
      background: var(--text-white);
      transition: var(--transition-smooth);
      border-radius: 2px;
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 80%;
      max-width: 360px;
      height: 100vh;
      background: rgba(10, 14, 23, 0.95);
      backdrop-filter: blur(30px);
      display: flex;
      flex-direction: column;
      padding: 100px 40px 40px;
      gap: 32px;
      transition: right 0.4s ease;
      z-index: 999;
      border-left: 1px solid var(--border-glow);
    }
    .mobile-menu.open {
      right: 0;
    }
    .mobile-menu .nav-link {
      font-size: 20px;
      font-weight: 600;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding: 100px 60px 60px;
      position: relative;
      background: var(--deep-space);
      background-image: radial-gradient(circle at 70% 30%, rgba(0,240,255,0.08) 0%, transparent 35%);
      overflow: hidden;
    }
    .hero-content {
      max-width: 650px;
      z-index: 2;
    }
    .hero h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.1;
      letter-spacing: -0.02em;
      color: var(--text-white);
      margin-bottom: 24px;
    }
    .hero h1 .highlight {
      color: var(--aurora-cyan);
      text-shadow: 0 0 30px rgba(0,240,255,0.5);
    }
    .hero p {
      font-size: 18px;
      color: var(--text-steel);
      max-width: 560px;
      margin-bottom: 40px;
    }
    .hero-visual {
      position: absolute;
      right: 0;
      top: 0;
      height: 100%;
      width: 50%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.5;
      mask-image: linear-gradient(to left, black 30%, transparent 100%);
      -webkit-mask-image: linear-gradient(to left, black 30%, transparent 100%);
    }
    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      color: var(--aurora-cyan);
      font-size: 28px;
      animation: bounce 2s infinite;
    }
    @keyframes bounce {
      0%,20%,50%,80%,100%{transform:translateX(-50%) translateY(0);}
      40%{transform:translateX(-50%) translateY(-12px);}
      60%{transform:translateX(-50%) translateY(-6px);}
    }

    /* 通用板块 */
    section {
      padding: 120px 0;
    }
    .section-title {
      font-size: 42px;
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 20px;
      line-height: 1.2;
    }
    .section-sub {
      color: var(--text-muted);
      max-width: 700px;
      margin-bottom: 60px;
      font-size: 17px;
    }

    /* 核心优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .adv-card {
      background: var(--card-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-lg);
      padding: 40px 32px;
      transition: var(--transition-smooth);
      position: relative;
    }
    .adv-card.featured {
      transform: scale(1.03);
      border-color: rgba(0,240,255,0.4);
      box-shadow: var(--shadow-glow);
      background: rgba(16, 24, 38, 0.8);
    }
    .adv-card:hover {
      transform: translateY(-10px);
      border-color: var(--aurora-cyan);
      box-shadow: 0 30px 45px rgba(0,240,255,0.15);
    }
    .adv-icon {
      font-size: 36px;
      color: var(--aurora-cyan);
      margin-bottom: 24px;
    }
    .adv-card h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--text-white);
      margin-bottom: 16px;
    }

    /* 解决方案混合网格 */
    .solutions-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .sol-card {
      background: var(--card-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-lg);
      padding: 36px;
      transition: var(--transition-smooth);
      position: relative;
      overflow: hidden;
    }
    .sol-card.wide {
      grid-column: span 2;
      display: flex;
      align-items: center;
      gap: 40px;
      background: linear-gradient(135deg, rgba(0,240,255,0.05) 0%, rgba(16,24,38,0.9) 100%);
    }
    .sol-card:hover {
      border-color: var(--aurora-cyan);
      box-shadow: var(--shadow-glow);
    }
    .sol-icon {
      font-size: 32px;
      color: var(--warm-gold);
    }

    /* 数据区 */
    .data-trust {
      background: var(--deep-blue);
      background-image: radial-gradient(circle at 20% 40%, rgba(0,240,255,0.05) 0%, transparent 50%);
      padding: 100px 0;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 40px;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: 52px;
      font-weight: 700;
      color: var(--warm-gold);
      text-shadow: 0 0 20px rgba(212,175,55,0.4);
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid var(--border-glow);
      transition: var(--transition-smooth);
    }
    .case-card:hover {
      transform: translateY(-12px);
      box-shadow: var(--shadow-glow);
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
      transition: transform 0.4s ease;
    }
    .case-card:hover .case-img {
      transform: scale(1.05);
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: rgba(16,24,38,0.4);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-sm);
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      color: var(--text-white);
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: rgba(0,0,0,0.2);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
    }

    /* CTA */
    .cta-block {
      background: linear-gradient(135deg, #0A0E17 0%, #101826 100%);
      position: relative;
    }

    /* Footer */
    .footer {
      background: #060A10;
      padding: 80px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .advantages-grid, .cases-grid { grid-template-columns: repeat(2,1fr); }
      .solutions-grid { grid-template-columns: 1fr; }
      .sol-card.wide { grid-column: span 1; flex-direction: column; }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .header { padding: 0 24px; }
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .hero { flex-direction: column; padding: 120px 24px 60px; }
      .hero h1 { font-size: 36px; }
      .section-title { font-size: 30px; }
      .advantages-grid, .cases-grid, .faq-grid, .footer-grid { grid-template-columns: 1fr; }
      .hero-visual { width: 100%; opacity: 0.25; }
    }