/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-red: #FF3366;
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(255, 255, 255, 0.08);
      --text-body: #E0E6F0;
      --text-secondary: #8892B0;
      --text-muted: #5A6380;
      --glass-blur: blur(24px);
      --radius-card: 20px;
      --radius-btn: 12px;
      --radius-container: 24px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-glow: 0 0 20px rgba(0, 240, 255, 0.15);
      --shadow-btn: 0 0 30px rgba(0, 240, 255, 0.4);
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--primary-deep);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      background-image: radial-gradient(circle at 30% 20%, rgba(0,240,255,0.08) 0%, transparent 45%),
                        radial-gradient(circle at 80% 70%, rgba(255,51,102,0.05) 0%, transparent 45%);
      background-attachment: fixed;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, input, textarea {
      font-family: inherit;
    }

    /* 导航 */
    .nav {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(10, 14, 39, 0.7);
      backdrop-filter: blur(30px);
      -webkit-backdrop-filter: blur(30px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.2);
      height: 72px;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      letter-spacing: -0.5px;
      background: linear-gradient(to right, #FFFFFF, #00F0FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: inline-block;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      position: relative;
      font-weight: 500;
      color: var(--text-secondary);
      font-size: 15px;
      padding: 8px 0;
      transition: color 0.2s;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--accent-cyan);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .nav-cta {
      background: linear-gradient(135deg, #00F0FF, #0088CC);
      color: #0A0E27;
      font-weight: 700;
      padding: 10px 24px;
      border-radius: 12px;
      font-size: 14px;
      box-shadow: 0 0 20px rgba(0,240,255,0.3);
      transition: box-shadow 0.2s, transform 0.2s;
    }
    .nav-cta:hover {
      box-shadow: 0 0 35px rgba(0,240,255,0.6);
      transform: scale(1.02);
    }
    .mobile-nav {
      display: none;
      position: fixed;
      bottom: 16px;
      left: 16px;
      right: 16px;
      background: rgba(10, 14, 39, 0.8);
      backdrop-filter: blur(30px);
      border: 1px solid rgba(0,240,255,0.15);
      border-radius: 40px;
      padding: 8px 20px;
      justify-content: space-around;
      z-index: 55;
      box-shadow: 0 10px 30px rgba(0,0,0,0.6);
    }
    .mobile-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 11px;
      color: var(--text-secondary);
      gap: 4px;
      font-weight: 500;
    }
    .mobile-nav a.active, .mobile-nav a:hover {
      color: var(--accent-cyan);
    }
    .mobile-nav i {
      font-size: 20px;
    }

    /* Hero */
    .hero {
      padding: 80px 0 100px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      position: relative;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      background-color: rgba(10, 14, 39, 0.75);
    }
    .hero-left {
      flex: 1 1 50%;
      max-width: 600px;
    }
    .hero h1 {
      font-size: 56px;
      font-weight: 700;
      letter-spacing: -1.5px;
      line-height: 1.2;
      background: linear-gradient(to right, #FFFFFF, #00F0FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .btn-primary {
      background: linear-gradient(135deg, #00F0FF, #0088CC);
      color: #0A0E27;
      font-weight: 700;
      padding: 16px 40px;
      border-radius: 12px;
      display: inline-block;
      box-shadow: 0 0 30px rgba(0,240,255,0.4);
      transition: box-shadow 0.25s, transform 0.2s;
      font-size: 16px;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      box-shadow: 0 0 50px rgba(0,240,255,0.7);
      transform: scale(1.02);
    }
    .hero-right {
      flex: 1 1 50%;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .data-card {
      background: rgba(10, 14, 39, 0.45);
      backdrop-filter: blur(24px);
      border: 1px solid rgba(0,240,255,0.15);
      border-radius: 20px;
      padding: 20px 24px;
      display: flex;
      align-items: center;
      gap: 16px;
      box-shadow: 0 8px 24px rgba(0,0,0,0.5);
    }
    .data-number {
      font-size: 36px;
      font-weight: 700;
      font-feature-settings: "tnum";
      color: var(--accent-cyan);
      text-shadow: 0 0 12px rgba(0,240,255,0.5);
      min-width: 140px;
    }
    .data-label {
      color: var(--text-secondary);
      font-size: 15px;
    }

    /* 通用区块 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 40px;
      font-weight: 600;
      letter-spacing: -0.5px;
      color: #FFFFFF;
      margin-bottom: 16px;
    }
    .section-sub {
      color: var(--text-secondary);
      max-width: 600px;
      margin-bottom: 48px;
      font-size: 16px;
    }

    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: rgba(10, 14, 39, 0.4);
      backdrop-filter: blur(24px);
      border: 1px solid rgba(0,240,255,0.12);
      border-radius: 20px;
      padding: 32px 24px;
      transition: all 0.3s ease;
      box-shadow: 0 4px 16px rgba(0,0,0,0.3);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      border-color: rgba(0,240,255,0.4);
      box-shadow: 0 0 20px rgba(0,240,255,0.15);
      transform: translateY(-4px);
    }
    .service-icon {
      font-size: 38px;
      color: var(--accent-cyan);
      margin-bottom: 20px;
      filter: drop-shadow(0 0 6px rgba(0,240,255,0.5));
    }
    .service-card h3 {
      font-size: 24px;
      font-weight: 600;
      color: #E0E6F0;
      margin-bottom: 12px;
    }
    .service-card p {
      color: var(--text-secondary);
      flex: 1;
      margin-bottom: 20px;
    }
    .text-link {
      color: var(--accent-cyan);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: gap 0.2s;
    }
    .text-link:hover {
      gap: 12px;
    }

    /* 数据对比 */
    .compare-row {
      display: flex;
      gap: 24px;
      flex-wrap: wrap;
    }
    .compare-card {
      flex: 1 1 280px;
      background: rgba(10, 14, 39, 0.35);
      backdrop-filter: blur(20px);
      border-radius: 24px;
      padding: 32px;
      border: 1px solid rgba(255,255,255,0.08);
    }
    .compare-card.old {
      border-left: 4px solid rgba(255,51,102,0.6);
    }
    .compare-card.new {
      border-left: 4px solid rgba(0,240,255,0.7);
    }
    .compare-title {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 24px;
    }
    .metric {
      display: flex;
      justify-content: space-between;
      margin-bottom: 16px;
    }
    .progress-bg {
      height: 6px;
      background: rgba(255,255,255,0.08);
      border-radius: 6px;
      margin-top: 8px;
      width: 100%;
    }
    .progress-fill {
      height: 6px;
      background: var(--accent-cyan);
      border-radius: 6px;
      width: 0%;
      transition: width 1s ease;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 16px;
    }
    .faq-item {
      background: rgba(10, 14, 39, 0.4);
      backdrop-filter: blur(20px);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: 20px;
      padding: 20px;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      color: #fff;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      margin-top: 0;
    }
    .faq-item.open .faq-answer {
      max-height: 150px;
      margin-top: 16px;
    }

    /* 表单 */
    .contact-card {
      background: rgba(6, 11, 32, 0.7);
      backdrop-filter: blur(28px);
      border: 1px solid rgba(0,240,255,0.25);
      border-radius: 32px;
      padding: 48px;
      max-width: 720px;
      margin: 0 auto;
      box-shadow: 0 0 40px rgba(0,240,255,0.1);
    }
    .input-field {
      background: transparent;
      border: none;
      border-bottom: 2px solid rgba(255,255,255,0.2);
      padding: 14px 8px;
      width: 100%;
      color: #fff;
      font-size: 16px;
      margin-bottom: 24px;
      transition: border 0.2s;
    }
    .input-field:focus {
      outline: none;
      border-bottom-color: var(--accent-cyan);
    }

    footer {
      background: #060B20;
      border-top: 1px solid rgba(255,255,255,0.05);
      padding: 32px 0;
      text-align: center;
      color: var(--text-muted);
    }

    @media (max-width: 1024px) {
      .hero {
        flex-direction: column;
        text-align: center;
      }
      .services-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-nav { display: flex; }
      .hero h1 { font-size: 36px; }
      .services-grid { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .compare-row { flex-direction: column; }
    }