/* roulang page: index */
:root {
      --primary-deep: #0B1A2F;
      --primary-bg: #132238;
      --accent-cyan: #00E5FF;
      --accent-orange: #FF5722;
      --text-primary: #ffffff;
      --text-secondary: rgba(255, 255, 255, 0.7);
      --text-muted: rgba(255, 255, 255, 0.5);
      --glass-bg: rgba(255, 255, 255, 0.04);
      --glass-border: rgba(255, 255, 255, 0.08);
      --glass-hover-brightness: 1.1;
      --card-radius: 16px;
      --button-radius: 50px;
      --section-gap: 120px;
      --container-width: 1280px;
      --transition-default: 0.3s ease;
      --font-mono: "SF Mono", "Cascadia Code", "Consolas", monospace;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      background: linear-gradient(135deg, #0B1A2F 0%, #132238 100%);
      color: var(--text-primary);
      line-height: 1.8;
      min-height: 100vh;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container-width);
      margin: 0 auto;
      padding: 0 32px;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-default);
    }
    button, input, textarea {
      font-family: inherit;
    }
    /* 沉浸式导航 */
    .nav-bar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(11, 26, 47, 0.85);
      backdrop-filter: blur(16px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.15);
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-width);
      margin: 0 auto;
      padding: 0 32px;
      height: 72px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--text-primary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo span {
      color: var(--accent-cyan);
      font-weight: 800;
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }
    .nav-links a {
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--accent-cyan);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      cursor: pointer;
      gap: 6px;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 28px;
      height: 2px;
      background: white;
      border-radius: 2px;
      transition: 0.3s;
    }
    /* Hero 双栏 */
    .hero-section {
      padding-top: 160px;
      padding-bottom: 100px;
      display: flex;
      align-items: center;
      gap: 60px;
      min-height: 90vh;
    }
    .hero-left {
      flex: 0 0 58%;
    }
    .hero-right {
      flex: 1;
      position: relative;
    }
    .hero-title {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.3;
      letter-spacing: -0.5px;
      margin-bottom: 24px;
    }
    .hero-title em {
      color: var(--accent-cyan);
      font-style: normal;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 40px;
      max-width: 540px;
    }
    .hero-cta {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
      align-items: center;
    }
    .btn-primary {
      background: var(--accent-cyan);
      color: #0B1A2F;
      border: none;
      padding: 14px 36px;
      border-radius: var(--button-radius);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      box-shadow: 0 0 20px rgba(0, 229, 255, 0.45);
      transition: all 0.25s;
      display: inline-block;
    }
    .btn-primary:hover {
      box-shadow: 0 0 32px rgba(0, 229, 255, 0.7);
      transform: scale(1.03);
    }
    .btn-ghost {
      background: transparent;
      border: 1px solid rgba(255, 255, 255, 0.3);
      color: white;
      padding: 14px 36px;
      border-radius: var(--button-radius);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      transition: all 0.25s;
      backdrop-filter: blur(10px);
    }
    .btn-ghost:hover {
      background: var(--accent-cyan);
      border-color: var(--accent-cyan);
      color: #0B1A2F;
      box-shadow: 0 0 18px rgba(0,229,255,0.3);
    }
    .hero-stats {
      display: flex;
      gap: 40px;
      margin-top: 48px;
    }
    .stat-item h3 {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--accent-cyan);
      font-feature-settings: "tnum";
    }
    .hero-image-bg {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 32px;
      height: 420px;
      width: 100%;
      position: relative;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
      border: 1px solid rgba(255,255,255,0.1);
    }
    .overlay-data {
      position: absolute;
      bottom: 20px;
      left: 20px;
      background: rgba(0,0,0,0.6);
      backdrop-filter: blur(12px);
      padding: 12px 20px;
      border-radius: 24px;
      font-size: 0.9rem;
      color: var(--accent-cyan);
      display: flex;
      gap: 20px;
    }
    /* 区块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }
    .section-desc {
      color: var(--text-secondary);
      margin-bottom: 56px;
      font-size: 1.1rem;
    }
    /* 亮点网格 2x3 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .highlight-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--card-radius);
      padding: 36px 28px;
      transition: all 0.3s;
      box-shadow: 0 8px 32px rgba(0,0,0,0.4);
    }
    .highlight-card:hover {
      background: rgba(255,255,255,0.07);
      border-color: rgba(0,229,255,0.3);
      transform: translateY(-5px);
    }
    .icon-circle {
      width: 52px;
      height: 52px;
      background: rgba(0,229,255,0.1);
      border-radius: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: var(--accent-cyan);
      font-size: 1.6rem;
    }
    .highlight-card h3 {
      font-size: 1.3rem;
      margin-bottom: 10px;
    }
    /* 案例瀑布 */
    .cases-waterfall {
      columns: 2;
      column-gap: 28px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 28px;
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--card-radius);
      overflow: hidden;
      transition: 0.3s;
    }
    .case-card:hover {
      border-color: rgba(0,229,255,0.4);
      transform: translateY(-4px);
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .case-tag {
      position: absolute;
      top: 16px;
      left: 16px;
      background: var(--accent-cyan);
      color: #0B1A2F;
      padding: 4px 14px;
      border-radius: 30px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    .case-content {
      padding: 24px;
    }
    .case-content h3 {
      font-size: 1.3rem;
      margin-bottom: 8px;
    }
    /* 方案对比 */
    .compare-row {
      display: flex;
      gap: 32px;
      align-items: stretch;
    }
    .plan-card {
      flex: 1;
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: 24px;
      padding: 40px 32px;
    }
    .plan-recommend {
      border-color: var(--accent-cyan);
      box-shadow: 0 0 24px rgba(0,229,255,0.2);
    }
    .plan-price {
      font-size: 2rem;
      font-weight: 700;
      margin: 20px 0 24px;
    }
    .feature-list {
      list-style: none;
      margin-bottom: 36px;
    }
    .feature-list li {
      padding: 10px 0;
      border-bottom: 1px solid rgba(255,255,255,0.06);
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      color: white;
      font-size: 1.1rem;
      font-weight: 500;
      padding: 24px 0;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.4s;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }
    /* 联系表单 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: start;
    }
    .form-input {
      width: 100%;
      background: rgba(255,255,255,0.04);
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: 14px;
      padding: 14px;
      color: white;
      margin-bottom: 20px;
      backdrop-filter: blur(12px);
    }
    .form-input:focus {
      outline: none;
      border-color: var(--accent-cyan);
      box-shadow: 0 0 10px rgba(0,229,255,0.3);
    }
    footer {
      background: #0A1625;
      padding: 70px 0 30px;
      margin-top: 80px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .hero-section { flex-direction: column; }
      .highlights-grid { grid-template-columns: repeat(2,1fr); }
      .cases-waterfall { columns: 1; }
      .contact-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-title { font-size: 2.4rem; }
      .compare-row { flex-direction: column; }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }