/* roulang page: index */
:root {
      --deep-bg: #0A0E27;
      --card-bg: #141832;
      --card-hover-bg: #1A2040;
      --primary-cyan: #00F0FF;
      --accent-pink: #FF2D78;
      --text-main: #E8ECF1;
      --text-secondary: #8892B0;
      --border-glow: rgba(0, 240, 255, 0.15);
      --border-hover: rgba(0, 240, 255, 0.5);
      --success-green: #00E676;
      --warning-amber: #FFB300;
      --gradient-btn: linear-gradient(135deg, #00F0FF 0%, #0088FF 100%);
      --gradient-hero: radial-gradient(ellipse at 50% 0%, #1A1F4A 0%, #0A0E27 70%);
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --font-data: 'DIN Alternate', 'Inter', 'PingFang SC', sans-serif;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --shadow-card: 0 4px 20px rgba(0, 240, 255, 0.08);
      --shadow-hover: 0 8px 32px rgba(0, 240, 255, 0.2);
      --container-max: 1280px;
      --section-padding: 80px;
      --card-padding: 32px;
      --nav-height: 72px;
      --bottom-nav-height: 64px;
    }

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

    body {
      background-color: var(--deep-bg);
      color: var(--text-main);
      font-family: var(--font-body);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

    button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
    }

    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border-glow);
      transition: background 0.3s ease, box-shadow 0.3s ease;
      height: var(--nav-height);
    }

    .main-header.scrolled {
      background: rgba(10, 14, 39, 0.95);
      box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--text-main);
      letter-spacing: 0.5px;
    }

    .logo-icon {
      color: var(--primary-cyan);
      font-size: 1.8rem;
      line-height: 1;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      font-weight: 500;
      color: var(--text-secondary);
    }

    .nav-links a {
      padding: 8px 0;
      position: relative;
      transition: color 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary-cyan);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-cyan);
      transition: width 0.2s ease;
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .btn-nav {
      background: var(--gradient-btn);
      color: white;
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      letter-spacing: 0.5px;
      transition: box-shadow 0.2s, transform 0.2s;
      font-size: 0.95rem;
      border: none;
    }

    .btn-nav:hover {
      box-shadow: 0 0 20px rgba(0, 240, 255, 0.5);
      transform: scale(1.02);
    }

    .mobile-menu-toggle {
      display: none;
      font-size: 1.8rem;
      color: var(--text-main);
      background: none;
      border: none;
    }

    /* 底部导航（移动端） */
    .bottom-mobile-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: rgba(10, 14, 39, 0.95);
      backdrop-filter: blur(20px);
      border-top: 1px solid var(--border-glow);
      z-index: 999;
      height: var(--bottom-nav-height);
      justify-content: space-around;
      align-items: center;
    }

    .bottom-mobile-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: var(--text-secondary);
      font-size: 0.7rem;
      font-weight: 500;
      gap: 4px;
      padding: 8px 12px;
    }

    .bottom-mobile-nav a i {
      font-size: 1.3rem;
    }

    .bottom-mobile-nav a.active {
      color: var(--primary-cyan);
    }

    /* 板块通用 */
    section {
      padding: var(--section-padding) 0;
    }

    .section-title {
      font-family: var(--font-heading);
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-main);
    }

    .section-subtitle {
      font-size: 1.125rem;
      color: var(--text-secondary);
      max-width: 700px;
      margin: 0 auto 48px;
      text-align: center;
    }

    .text-center {
      text-align: center;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .card {
      background: var(--card-bg);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-card);
      padding: var(--card-padding);
      transition: transform 0.25s ease, border-color 0.25s, box-shadow 0.25s, background 0.25s;
      box-shadow: var(--shadow-card);
    }

    .card:hover {
      transform: translateY(-4px);
      border-color: var(--border-hover);
      background: var(--card-hover-bg);
      box-shadow: var(--shadow-hover);
    }

    /* Hero */
    .hero {
      padding-top: calc(var(--nav-height) + 60px);
      padding-bottom: 80px;
      background: var(--gradient-hero);
      position: relative;
      overflow: hidden;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
    }

    .hero-left {
      flex: 1;
    }

    .hero-right {
      flex: 1;
      position: relative;
    }

    .hero-right img {
      border-radius: 16px;
      box-shadow: 0 0 40px rgba(0, 240, 255, 0.2);
    }

    .hero-h1 {
      font-family: var(--font-heading);
      font-size: 3rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
      color: white;
    }

    .hero-lead {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 90%;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--gradient-btn);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      letter-spacing: 0.5px;
      transition: box-shadow 0.2s, transform 0.2s;
      box-shadow: 0 0 12px rgba(0,240,255,0.3);
    }

    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(0,240,255,0.6);
      transform: scale(1.02);
    }

    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--primary-cyan);
      color: var(--primary-cyan);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      transition: background 0.2s;
    }

    .btn-secondary:hover {
      background: rgba(0,240,255,0.08);
    }

    /* 功能交替 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }

    .feature-row.reverse {
      flex-direction: row-reverse;
    }

    .feature-text {
      flex: 1;
    }

    .feature-img {
      flex: 1;
      border-radius: 16px;
      overflow: hidden;
    }

    .feature-list {
      list-style: none;
      margin-top: 20px;
    }

    .feature-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 12px;
      color: var(--text-secondary);
    }

    .feature-list li::before {
      content: "●";
      color: var(--primary-cyan);
      font-size: 0.8rem;
    }

    /* 案例横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scrollbar-width: thin;
      scrollbar-color: var(--primary-cyan) var(--card-bg);
    }

    .case-card {
      min-width: 240px;
      background: var(--card-bg);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      text-align: center;
    }

    .case-number {
      font-family: var(--font-data);
      font-size: 2.8rem;
      font-weight: 700;
      background: linear-gradient(135deg, #00F0FF, #0088FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* 价格卡 */
    .pricing-card.featured {
      border-color: var(--primary-cyan);
      box-shadow: 0 0 28px rgba(0,240,255,0.25);
      position: relative;
    }

    .badge-popular {
      background: var(--accent-pink);
      color: white;
      font-size: 0.8rem;
      font-weight: 600;
      padding: 4px 16px;
      border-radius: 20px;
      position: absolute;
      top: -14px;
      right: 20px;
    }

    .price {
      font-family: var(--font-data);
      font-size: 2.4rem;
      font-weight: 700;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-glow);
      padding: 20px 0;
      cursor: pointer;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 1.1rem;
    }

    .faq-answer {
      color: #B0B8D0;
      padding: 12px 0 0 20px;
      border-left: 2px solid var(--primary-cyan);
      margin-top: 8px;
      display: none;
    }

    .faq-item.open .faq-answer {
      display: block;
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0A0E27 0%, #1A1F4A 100%);
      position: relative;
    }

    .btn-light {
      background: white;
      color: #0A0E27;
      padding: 18px 48px;
      font-weight: 700;
      border-radius: var(--radius-btn);
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }

    @media (max-width: 768px) {
      .nav-links, .btn-nav { display: none; }
      .mobile-menu-toggle { display: block; }
      .bottom-mobile-nav { display: flex; }
      .hero-grid { flex-direction: column; }
      .grid-3, .grid-2 { grid-template-columns: 1fr; }
      .feature-row, .feature-row.reverse { flex-direction: column; }
      .hero-h1 { font-size: 2rem; }
      .section-title { font-size: 1.8rem; }
      .footer-grid { grid-template-columns: 1fr; }
      section { padding: 48px 0; }
    }