/* roulang page: index */
:root {
      --primary: #0A1F3F;
      --accent: #F5A623;
      --bg: #F9FAFB;
      --card-bg: #FFFFFF;
      --text: #1F2937;
      --text-secondary: #6B7280;
      --border: #E5E7EB;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', system-ui, -apple-system, sans-serif;
      --transition-default: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      scroll-padding-top: 80px;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.65;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    img {
      display: block;
      max-width: 100%;
      height: auto;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-default);
    }
    button, input {
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }

    /* 页头导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 50;
      transition: box-shadow 0.15s ease;
      border-bottom: 1px solid transparent;
    }
    #header.scrolled {
      box-shadow: 0 2px 10px rgba(0,0,0,0.04);
      border-bottom-color: var(--border);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      display: flex;
      align-items: center;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.3px;
    }
    .logo i {
      color: var(--accent);
      margin-left: 6px;
      font-size: 1.7rem;
    }
    .desktop-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .desktop-menu a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text);
      transition: color 0.2s;
    }
    .desktop-menu a:hover {
      color: var(--accent);
    }
    .btn-primary {
      background: var(--accent);
      color: #fff;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-primary:hover {
      background: #E09510;
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(245,166,35,0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: all 0.2s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: #fff;
      transform: translateY(-2px);
    }
    .btn-text {
      color: var(--accent);
      font-weight: 500;
      position: relative;
      transition: color 0.2s;
    }
    .btn-text::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0%;
      height: 1.5px;
      background: var(--accent);
      transition: width 0.25s ease;
    }
    .btn-text:hover::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--primary);
      border-radius: 2px;
      transition: 0.2s;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 280px;
      height: 100vh;
      background: #fff;
      box-shadow: -5px 0 25px rgba(0,0,0,0.05);
      padding: 24px;
      transition: right 0.3s ease;
      z-index: 60;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .mobile-menu.open {
      right: 0;
    }
    .mobile-menu a {
      font-weight: 500;
      font-size: 1.1rem;
    }
    @media (max-width: 768px) {
      .desktop-menu {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }

    /* 区块间距 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 56px 0;
      }
    }

    /* Hero */
    #hero {
      padding-top: 120px;
      background: var(--bg);
    }
    .hero-grid {
      display: flex;
      gap: 50px;
      align-items: center;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-right {
      flex: 1 1 50%;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .hero-right img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    h1 {
      font-size: 2.8rem;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: var(--primary);
      margin-bottom: 18px;
    }
    .hero-sub {
      font-size: 1.1rem;
      color: var(--text-secondary);
      max-width: 480px;
      margin-bottom: 28px;
    }
    .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      align-items: center;
      margin-bottom: 24px;
    }
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 12px;
      font-size: 0.9rem;
      color: var(--text-secondary);
    }
    .trust-badge i {
      color: var(--accent);
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column-reverse;
        gap: 32px;
      }
      h1 {
        font-size: 2.2rem;
      }
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .highlight-card {
      background: var(--card-bg);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      transition: transform 0.25s ease, box-shadow 0.25s ease;
      text-align: left;
    }
    .highlight-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 60px;
      height: 60px;
      background: #E8F0FE;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      font-size: 1.8rem;
      margin-bottom: 20px;
    }
    .highlight-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .highlight-card p {
      color: var(--text-secondary);
      margin-bottom: 14px;
    }
    @media (max-width: 1024px) {
      .highlights-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .highlights-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 案例瀑布 */
    .cases-masonry {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 28px;
    }
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      border: 1px solid var(--border);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: transform 0.25s, box-shadow 0.25s;
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
    }
    .case-body {
      padding: 20px 20px 24px;
    }
    .tag {
      background: #E8F0FE;
      color: var(--primary);
      font-size: 0.8rem;
      font-weight: 500;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 10px;
    }
    .case-body h3 {
      font-size: 1.2rem;
      font-weight: 600;
      margin-bottom: 8px;
    }
    @media (max-width: 768px) {
      .cases-masonry {
        grid-template-columns: 1fr;
      }
    }

    /* 方案对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      gap: 24px;
    }
    .vs-badge {
      width: 56px;
      height: 56px;
      background: var(--accent);
      color: #fff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.2rem;
      box-shadow: 0 6px 14px rgba(245,166,35,0.35);
    }
    .plan-card {
      background: var(--card-bg);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      padding: 30px 24px;
      box-shadow: var(--shadow-sm);
      position: relative;
    }
    .plan-pro {
      border-left: 4px solid var(--accent);
    }
    .plan-card h3 {
      font-size: 1.5rem;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .plan-list {
      list-style: none;
      margin: 20px 0;
    }
    .plan-list li {
      margin-bottom: 10px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .plan-list i.fa-check {
      color: var(--accent);
    }
    .plan-list i.fa-times {
      color: #9CA3AF;
    }
    @media (max-width: 768px) {
      .compare-grid {
        grid-template-columns: 1fr;
        gap: 16px;
      }
      .vs-badge {
        margin: 8px auto;
      }
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 18px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      font-size: 1.1rem;
    }
    .faq-question i {
      color: var(--accent);
      transition: transform 0.3s ease;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    .faq-item.active .faq-question i {
      transform: rotate(45deg);
    }

    /* CTA 全幅 */
    #cta {
      background: linear-gradient(135deg, #E8F0FE 0%, #F3F4F6 100%);
    }
    .cta-content {
      text-align: center;
    }
    .cta-content h2 {
      font-size: 2rem;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .cta-sub {
      color: var(--text-secondary);
      margin-bottom: 28px;
    }

    /* 页脚 */
    #footer {
      background: var(--primary);
      color: #CBD5E1;
      padding: 60px 0 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 32px;
    }
    .footer-logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: #fff;
      margin-bottom: 12px;
    }
    .footer-grid h4 {
      color: #fff;
      margin-bottom: 16px;
      font-weight: 600;
    }
    .footer-grid a {
      display: block;
      margin-bottom: 8px;
      color: #CBD5E1;
    }
    .footer-grid a:hover {
      color: var(--accent);
    }
    .copyright {
      background: #091A33;
      padding: 18px 0;
      margin-top: 48px;
      text-align: center;
      font-size: 0.9rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 520px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }

    h2 {
      font-size: 2rem;
      font-weight: 600;
      margin-bottom: 28px;
      color: var(--primary);
    }
    .section-header {
      text-align: center;
      margin-bottom: 48px;
    }