/* roulang page: index */
/* ===== 设计变量与基础重置 ===== */
    :root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-purple: #7B2FFF;
      --signal-green: #00E676;
      --card-bg: rgba(30, 35, 54, 0.6);
      --card-border: rgba(0, 240, 255, 0.15);
      --text-body: #E8ECF1;
      --text-white: #FFFFFF;
      --neutral-gray: #1E2336;
      --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);
      --shadow-glow: 0 8px 40px rgba(0, 240, 255, 0.25);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --transition: all 0.3s ease;
      --container-max: 1280px;
    }

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

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      background-color: var(--primary-deep);
      color: var(--text-body);
      line-height: 1.8;
      font-size: 16px;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 排版体系 */
    h1 {
      font-size: 48px;
      line-height: 1.2;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--text-white);
    }
    h2 {
      font-size: 36px;
      line-height: 1.3;
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 12px;
    }
    h3 {
      font-size: 24px;
      line-height: 1.4;
      font-weight: 600;
      color: var(--text-white);
    }
    h4 {
      font-size: 20px;
      font-weight: 600;
      color: var(--text-white);
    }
    .lead {
      font-size: 18px;
      color: var(--text-body);
      margin-bottom: 8px;
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 span {
      color: var(--accent-cyan);
    }
    .decorative-line {
      width: 60px;
      height: 4px;
      background: linear-gradient(90deg, var(--accent-cyan), var(--accent-purple));
      margin: 16px auto 0;
      border-radius: 2px;
    }

    /* 按钮系统 */
    .btn {
      display: inline-block;
      padding: 12px 32px;
      border-radius: 40px;
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
      cursor: pointer;
      border: none;
      transition: all 0.25s ease;
      text-align: center;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--accent-cyan), var(--accent-purple));
      color: #0A0E27;
      box-shadow: 0 0 20px rgba(0, 240, 255, 0.4);
    }
    .btn-primary:hover {
      box-shadow: 0 0 35px rgba(0, 240, 255, 0.7);
      transform: translateY(-2px);
    }
    .btn-secondary {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      margin-left: 16px;
    }
    .btn-secondary:hover {
      background: rgba(0, 240, 255, 0.1);
      border-color: var(--accent-purple);
    }

    /* ===== 导航 (Mega Menu 风格) ===== */
    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 24px;
      font-weight: 800;
      background: linear-gradient(to right, var(--accent-cyan), var(--accent-purple));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 14px;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.3s;
      box-shadow: 0 0 8px var(--accent-cyan);
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    /* Mega面板 (纯CSS) */
    .mega-trigger {
      position: relative;
      cursor: pointer;
    }
    .mega-panel {
      position: absolute;
      top: 100%;
      right: 0;
      background: rgba(30, 35, 54, 0.9);
      backdrop-filter: blur(24px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 24px;
      display: flex;
      gap: 24px;
      opacity: 0;
      visibility: hidden;
      transform: translateY(10px);
      transition: all 0.3s ease;
      width: 480px;
      box-shadow: var(--shadow-card);
      z-index: 99;
    }
    .mega-trigger:hover .mega-panel {
      opacity: 1;
      visibility: visible;
      transform: translateY(0);
    }
    .mega-card {
      background: rgba(10, 14, 39, 0.7);
      border-radius: var(--radius-md);
      overflow: hidden;
      border: 1px solid transparent;
      transition: var(--transition);
      width: 50%;
    }
    .mega-card:hover {
      border-color: var(--accent-cyan);
      box-shadow: 0 0 20px rgba(0, 240, 255, 0.3);
    }
    .mega-card img {
      height: 80px;
      object-fit: cover;
    }
    .mega-card p {
      padding: 8px;
      font-size: 14px;
      font-weight: 600;
    }

    /* 移动端汉堡菜单 */
    #menu-toggle {
      display: none;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--text-body);
      transition: var(--transition);
    }

    /* ===== Hero 双栏杂志流 ===== */
    .hero {
      padding: 140px 0 80px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      min-height: 90vh;
      display: flex;
      align-items: center;
    }
    .hero::before {
      content: '';
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: linear-gradient(90deg, rgba(10,14,39,0.92) 40%, rgba(10,14,39,0.7) 100%);
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 48px;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 0 0 55%;
    }
    .hero-left h1 {
      margin-bottom: 20px;
    }
    .hero-left .lead {
      margin-bottom: 32px;
      font-size: 20px;
    }
    .hero-right {
      flex: 0 0 40%;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .data-card-stack {
      position: relative;
    }
    .data-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .data-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-glow);
      border-color: var(--accent-cyan);
    }
    .data-card .stat {
      font-size: 32px;
      font-weight: 700;
      color: var(--accent-cyan);
      font-family: 'Inter', monospace;
    }
    .data-card .label {
      color: var(--accent-purple);
      font-weight: 600;
      margin-top: 8px;
    }

    /* ===== 核心亮点网格 ===== */
    .highlights {
      padding: 80px 0;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .highlight-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      text-align: center;
      transition: var(--transition);
    }
    .highlight-card:hover {
      transform: translateY(-6px);
      border-color: var(--accent-cyan);
      box-shadow: var(--shadow-glow);
    }
    .highlight-icon {
      font-size: 40px;
      margin-bottom: 16px;
      color: var(--accent-cyan);
    }
    .highlight-number {
      font-size: 36px;
      font-weight: 800;
      color: var(--accent-cyan);
      font-family: 'Inter', monospace;
    }

    /* ===== 案例瀑布流 ===== */
    .cases {
      padding: 80px 0;
      background: rgba(10, 14, 39, 0.5);
    }
    .masonry {
      columns: 3;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--card-border);
      transition: var(--transition);
    }
    .case-card:hover {
      border-color: var(--accent-cyan);
      box-shadow: var(--shadow-glow);
      transform: translateY(-4px);
    }
    .case-card img {
      width: 100%;
      object-fit: cover;
    }
    .case-info {
      padding: 16px;
    }
    .case-info h4 {
      margin-bottom: 8px;
    }
    .tag {
      display: inline-block;
      background: rgba(123, 47, 255, 0.2);
      color: var(--accent-purple);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 600;
    }

    /* ===== 方案对比表 ===== */
    .compare {
      padding: 80px 0;
    }
    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      align-items: start;
    }
    .plan-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      padding: 32px 24px;
      border: 1px solid var(--card-border);
      transition: var(--transition);
    }
    .plan-card.featured {
      border-color: var(--accent-purple);
      box-shadow: 0 0 30px rgba(123, 47, 255, 0.3);
      transform: scale(1.02);
    }
    .plan-card h3 {
      margin-bottom: 16px;
    }
    .plan-price {
      font-size: 32px;
      font-weight: 800;
      color: var(--accent-cyan);
    }
    .plan-features {
      list-style: none;
      margin: 24px 0;
    }
    .plan-features li {
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    /* FAQ */
    .faq {
      padding: 80px 0;
      background: rgba(10, 14, 39, 0.5);
    }
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    details {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-md);
      padding: 20px;
      cursor: pointer;
      transition: var(--transition);
    }
    details[open] {
      border-color: var(--accent-cyan);
      box-shadow: 0 0 20px rgba(0,240,255,0.2);
    }
    summary {
      font-weight: 600;
      font-size: 18px;
      list-style: none;
      display: flex;
      justify-content: space-between;
    }
    summary::-webkit-details-marker { display: none; }

    /* CTA横幅 */
    .cta-banner {
      padding: 80px 0;
      text-align: center;
      background: #060A1A;
    }
    .trust-badges {
      display: flex;
      justify-content: center;
      gap: 32px;
      margin-top: 24px;
      color: var(--text-body);
    }

    /* 页脚 */
    footer {
      background: #060A1A;
      border-top: 1px solid var(--accent-cyan);
      padding: 60px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer-bottom {
      text-align: center;
      padding-top: 24px;
      border-top: 1px solid rgba(255,255,255,0.1);
      font-size: 14px;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .masonry { columns: 2; }
      .compare-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      #menu-toggle:checked ~ .nav-links {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(10,14,39,0.95);
        backdrop-filter: blur(20px);
        padding: 24px;
      }
      .hero .container { flex-direction: column; }
      .hero-left, .hero-right { flex: auto; }
      .faq-grid { grid-template-columns: 1fr; }
      .masonry { columns: 1; }
      .footer-grid { grid-template-columns: 1fr; }
    }