/* roulang page: index */
:root {
      --deep-blue: #0A1128;
      --electric-cyan: #00E5FF;
      --energy-orange: #FF5722;
      --card-bg: rgba(15, 25, 45, 0.7);
      --text-primary: #E0E6F0;
      --text-white: #FFFFFF;
      --text-muted: #8892B0;
      --border-glow: rgba(0, 229, 255, 0.15);
      --border-strong: rgba(0, 229, 255, 0.25);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-hover: 0 12px 40px rgba(0, 229, 255, 0.15);
      --radius-card: 16px;
      --radius-btn: 30px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'Roboto', sans-serif;
      --transition: all 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--deep-blue);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, input, textarea {
      font-family: inherit;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 80px;
      background: linear-gradient(180deg, rgba(10,17,40,0.95) 0%, rgba(10,17,40,0.5) 100%);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,229,255,0.1);
      transition: var(--transition);
    }
    .header.scrolled {
      background: rgba(10, 17, 40, 0.85);
      backdrop-filter: blur(24px);
      border-bottom: 1px solid var(--border-glow);
      box-shadow: 0 4px 20px rgba(0,0,0,0.6);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 80px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 24px;
      color: var(--text-white);
      letter-spacing: -0.3px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--electric-cyan);
      clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
      display: inline-block;
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }
    .nav-links a {
      color: #B0C4DE;
      font-weight: 500;
      font-size: 16px;
      padding: 6px 0;
      position: relative;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--electric-cyan);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--electric-cyan);
      transition: width 0.3s;
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--electric-cyan);
      color: var(--deep-blue);
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      letter-spacing: 0.3px;
    }
    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(0, 229, 255, 0.7);
      filter: brightness(1.1);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid rgba(255,255,255,0.4);
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: var(--transition);
      backdrop-filter: blur(8px);
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.08);
      border-color: white;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 1100;
    }
    .hamburger span {
      width: 26px;
      height: 3px;
      background: white;
      border-radius: 2px;
      transition: var(--transition);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(5, 10, 25, 0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      z-index: 1050;
      opacity: 0;
      visibility: hidden;
      transition: opacity 0.4s ease, visibility 0.4s;
    }
    .mobile-menu.active {
      opacity: 1;
      visibility: visible;
    }
    .mobile-menu a {
      font-size: 28px;
      font-weight: 600;
      color: white;
      transition: color 0.3s;
    }
    .mobile-menu a:hover {
      color: var(--electric-cyan);
    }
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background: radial-gradient(circle at 30% 40%, #0a1a3a 0%, #0A1128 70%);
      overflow: hidden;
    }
    .hero::before {
      content: '';
      position: absolute;
      width: 600px;
      height: 600px;
      background: radial-gradient(circle, rgba(0,229,255,0.12) 0%, transparent 70%);
      top: -100px;
      right: -100px;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: clamp(40px, 6vw, 64px);
      font-weight: 700;
      line-height: 1.2;
      color: white;
      margin-bottom: 24px;
    }
    .hero-text h1 span {
      background: linear-gradient(135deg, #00E5FF, #6EE7FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-sub {
      font-size: 20px;
      color: #B0C4DE;
      margin-bottom: 36px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-image img {
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
      max-height: 420px;
      object-fit: cover;
    }
    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 40px;
      font-weight: 700;
      color: white;
      margin-bottom: 16px;
      line-height: 1.3;
    }
    .section-desc {
      color: var(--text-muted);
      font-size: 18px;
      max-width: 700px;
    }
    /* 优势混合网格 */
    .advantages-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr;
      gap: 24px;
      margin-top: 48px;
    }
    .adv-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: var(--radius-card);
      padding: 32px;
      transition: var(--transition);
    }
    .adv-card:hover {
      border-color: var(--border-strong);
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .adv-large {
      grid-row: span 2;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .adv-small-group {
      display: grid;
      grid-template-rows: 1fr 1fr;
      gap: 24px;
    }
    .adv-icon {
      font-size: 32px;
      color: var(--electric-cyan);
      margin-bottom: 20px;
    }
    .adv-card h3 {
      font-size: 24px;
      font-weight: 600;
      color: white;
      margin-bottom: 12px;
    }
    /* 数据带 */
    .stats-band {
      background: #060B1A;
      padding: 48px 0;
      border-top: 1px solid rgba(0,229,255,0.15);
      border-bottom: 1px solid rgba(0,229,255,0.15);
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--electric-cyan);
    }
    .stat-label {
      color: var(--text-muted);
      font-size: 16px;
      margin-top: 8px;
    }
    /* 方案图文交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-img {
      flex: 1;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 20px 35px rgba(0,0,0,0.6);
    }
    .solution-img img {
      width: 100%;
      height: 320px;
      object-fit: cover;
      transition: transform 0.5s;
    }
    .solution-img:hover img {
      transform: scale(1.05);
    }
    .solution-text {
      flex: 1;
    }
    .solution-text h2 {
      font-size: 36px;
      font-weight: 700;
      color: white;
      margin-bottom: 16px;
    }
    .feature-list {
      list-style: none;
      margin: 24px 0;
    }
    .feature-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 14px;
      color: #E0E6F0;
    }
    .feature-list li::before {
      content: "✓";
      color: var(--electric-cyan);
      font-weight: bold;
    }
    .text-link {
      color: var(--electric-cyan);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }
    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 28px;
      margin-top: 48px;
    }
    .case-card {
      background: #111B2F;
      border-radius: 14px;
      overflow: hidden;
      box-shadow: 0 4px 20px rgba(0,0,0,0.5);
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: 0 12px 30px rgba(0,229,255,0.2);
      transform: translateY(-5px);
    }
    .case-img {
      height: 200px;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.04);
    }
    .case-info {
      padding: 20px;
      background: linear-gradient(180deg, rgba(17,27,47,0.9) 0%, #111B2F 100%);
    }
    .case-tag {
      background: rgba(0,229,255,0.15);
      color: var(--electric-cyan);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
      display: inline-block;
      margin-bottom: 8px;
    }
    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      margin-top: 40px;
    }
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      align-items: baseline;
      gap: 16px;
      font-size: 20px;
      font-weight: 600;
      color: white;
    }
    .faq-num {
      font-family: var(--font-number);
      font-size: 28px;
      font-weight: 700;
      color: rgba(0,229,255,0.3);
      min-width: 40px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: #B0C4DE;
      padding-left: 56px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
      padding-bottom: 8px;
      background: rgba(0,229,255,0.03);
    }
    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0A1128 0%, #0B1A3A 100%);
      text-align: center;
    }
    .cta-form {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      justify-content: center;
      margin-top: 36px;
    }
    .cta-form input {
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: 8px;
      padding: 14px 20px;
      color: white;
      min-width: 220px;
      outline: none;
    }
    .cta-form input:focus {
      border-color: var(--electric-cyan);
      box-shadow: 0 0 10px rgba(0,229,255,0.3);
    }
    /* 页脚 */
    .footer {
      background: #060B1A;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
    }
    .footer-logo {
      font-size: 24px;
      font-weight: 700;
      color: white;
      margin-bottom: 14px;
    }
    .social-icons {
      display: flex;
      gap: 16px;
      margin-top: 20px;
    }
    .social-icons a {
      width: 36px;
      height: 36px;
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.08);
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      color: var(--text-muted);
    }
    @media (max-width: 1024px) {
      .hero-content {
        flex-direction: column;
      }
      .advantages-grid {
        grid-template-columns: 1fr;
      }
      .solution-row, .solution-row.reverse {
        flex-direction: column;
      }
      .faq-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-text h1 { font-size: 36px; }
      .section-title { font-size: 28px; }
      .stats-grid { gap: 24px; }
    }