/* roulang page: index */
:root {
      --primary-deep: #0A1F3F;
      --accent-cyan: #00E5FF;
      --bg-light: #F4F6FA;
      --card-white: #FFFFFF;
      --text-body: #1E2B3C;
      --text-muted: #5A6B7F;
      --border-light: #E2E8F0;
      --shadow-sm: 0 4px 20px rgba(10, 31, 63, 0.06);
      --shadow-hover: 0 12px 32px rgba(10, 31, 63, 0.12);
      --radius-card: 12px;
      --radius-btn: 24px;
      --radius-sm: 8px;
      --transition: 0.25s ease;
      --font-title: 'Inter', 'Noto Sans SC', sans-serif;
      --font-body: 'Noto Sans SC', 'Inter', sans-serif;
      --font-mono: 'JetBrains Mono', monospace;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-title);
      letter-spacing: -0.02em;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航卡片化控制面板 */
    .nav-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      margin: 16px auto 0;
      padding: 12px 28px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      position: sticky;
      top: 16px;
      z-index: 50;
      width: 90%;
      max-width: 1200px;
      transition: var(--transition);
    }
    .nav-logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 1.6rem;
      color: var(--primary-deep);
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
    }
    .nav-logo i {
      color: var(--accent-cyan);
      font-size: 1.8rem;
    }
    .nav-menu {
      display: flex;
      gap: 8px;
      align-items: center;
    }
    .nav-item {
      background: transparent;
      border: 1px solid transparent;
      padding: 8px 16px;
      border-radius: var(--radius-sm);
      font-weight: 500;
      color: var(--text-body);
      transition: var(--transition);
      text-decoration: none;
      font-size: 0.95rem;
      display: inline-block;
    }
    .nav-item:hover {
      border-color: var(--accent-cyan);
      color: var(--accent-cyan);
      background: rgba(0,229,255,0.03);
    }
    .btn-cta {
      background: var(--accent-cyan);
      color: white;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      border: none;
      transition: var(--transition);
      text-decoration: none;
      display: inline-block;
      font-size: 0.95rem;
      box-shadow: 0 4px 10px rgba(0,229,255,0.2);
    }
    .btn-cta:hover {
      background: var(--primary-deep);
      color: white;
      box-shadow: 0 8px 18px rgba(10,31,63,0.25);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary-deep);
      cursor: pointer;
    }
    /* Hero 双栏 */
    .hero {
      display: flex;
      align-items: center;
      gap: 48px;
      padding: 64px 0 80px;
      position: relative;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-right {
      flex: 1 1 50%;
      position: relative;
    }
    .hero h1 {
      font-size: 3.4rem;
      font-weight: 700;
      color: var(--primary-deep);
      margin-bottom: 20px;
      line-height: 1.2;
    }
    .hero .subtitle {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 32px;
    }
    .hero-stats {
      display: flex;
      gap: 24px;
      margin-top: 28px;
      flex-wrap: wrap;
    }
    .stat-badge {
      background: white;
      padding: 10px 18px;
      border-radius: 30px;
      box-shadow: var(--shadow-sm);
      font-weight: 600;
      color: var(--primary-deep);
      font-family: var(--font-mono);
    }
    .hero-image {
      width: 100%;
      border-radius: 16px;
      box-shadow: var(--shadow-hover);
      object-fit: cover;
      aspect-ratio: 4/3;
      background: #d9e2ef;
    }
    .semi-transparent-card {
      position: absolute;
      bottom: -18px;
      right: -18px;
      background: rgba(255,255,255,0.9);
      backdrop-filter: blur(8px);
      padding: 14px 20px;
      border-radius: 12px;
      box-shadow: var(--shadow-sm);
      font-weight: 600;
      color: var(--primary-deep);
      font-size: 0.9rem;
    }
    /* 板块标题 */
    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      color: var(--primary-deep);
      margin-bottom: 16px;
    }
    .section-desc {
      color: var(--text-muted);
      margin-bottom: 40px;
      font-size: 1.1rem;
    }
    section {
      padding: 80px 0;
    }
    /* 亮点网格 3x2 卡片 */
    .grid-cards {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: left;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .feature-icon {
      font-size: 2rem;
      color: var(--accent-cyan);
      margin-bottom: 18px;
      display: inline-block;
    }
    .feature-card h3 {
      font-size: 1.4rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .feature-card p {
      color: var(--text-muted);
    }
    /* 案例瀑布 */
    .masonry-cases {
      column-count: 3;
      column-gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      margin-bottom: 24px;
      break-inside: avoid;
      overflow: hidden;
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      width: 100%;
      display: block;
      border-radius: 8px 8px 0 0;
      transition: transform 0.3s ease;
    }
    .case-card:hover .case-img {
      transform: scale(1.03);
    }
    .case-content {
      padding: 20px;
    }
    .case-tag {
      background: rgba(0,229,255,0.1);
      color: var(--primary-deep);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.75rem;
      font-weight: 600;
    }
    /* 方案对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .plan-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      border: 2px solid transparent;
      transition: var(--transition);
      position: relative;
    }
    .plan-card.recommend {
      border-color: var(--accent-cyan);
    }
    .badge-recommend {
      background: var(--accent-cyan);
      color: white;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.75rem;
      position: absolute;
      top: -12px;
      right: 20px;
      font-weight: 600;
    }
    .plan-price {
      font-family: var(--font-mono);
      font-size: 1.8rem;
      font-weight: 600;
    }
    .plan-features {
      list-style: none;
      margin: 20px 0;
      padding: 0;
    }
    .plan-features li {
      padding: 8px 0;
      border-bottom: 1px solid var(--border-light);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .btn-outline {
      border: 2px solid var(--primary-deep);
      background: transparent;
      padding: 10px 24px;
      border-radius: 24px;
      font-weight: 600;
      color: var(--primary-deep);
      transition: var(--transition);
    }
    .btn-outline:hover {
      background: var(--primary-deep);
      color: white;
    }
    /* FAQ */
    .accordion-card {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-sm);
    }
    .accordion-title {
      font-size: 1.1rem;
      font-weight: 600;
      padding: 18px 24px;
      color: var(--primary-deep);
      transition: 0.3s;
    }
    .accordion-title:hover {
      color: var(--accent-cyan);
    }
    .accordion-content {
      border-top: 1px solid var(--border-light);
      padding: 18px 24px;
      color: var(--text-muted);
    }
    /* CTA 横幅 */
    .cta-banner {
      background: var(--primary-deep);
      padding: 64px 24px;
      text-align: center;
      border-radius: 24px;
      color: white;
      margin: 40px 0;
    }
    .cta-banner h2 {
      color: white;
      font-weight: 600;
    }
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      color: #B0C4DE;
    }
    footer {
      background: var(--primary-deep);
      padding: 60px 0 30px;
      margin-top: 60px;
    }
    .footer-links a {
      color: #B0C4DE;
      text-decoration: none;
      display: block;
      margin-bottom: 6px;
      transition: 0.2s;
    }
    .footer-links a:hover {
      color: var(--accent-cyan);
    }
    @media (max-width: 1024px) {
      .grid-cards { grid-template-columns: repeat(2,1fr); }
      .masonry-cases { column-count: 2; }
      .compare-grid { grid-template-columns: 1fr; }
      .hero { flex-direction: column; }
      .hero h1 { font-size: 2.6rem; }
    }
    @media (max-width: 640px) {
      .nav-menu { display: none; width: 100%; flex-direction: column; margin-top: 16px; }
      .nav-menu.active { display: flex; }
      .hamburger { display: block; }
      .grid-cards { grid-template-columns: 1fr; }
      .masonry-cases { column-count: 1; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 2rem; }
      .nav-card { width: 96%; }
    }