/* roulang page: index */
:root {
      --primary: #E8423F;
      --primary-dark: #C72C2A;
      --secondary: #1A1A2E;
      --background: #F9F9FB;
      --accent-gold: #FFB800;
      --white: #FFFFFF;
      --gray-50: #F4F4F7;
      --gray-100: #E9E9EF;
      --gray-200: #D1D1DB;
      --gray-600: #6B6B7B;
      --gray-800: #2D2D3A;
      --text-primary: #1F1F2E;
      --text-secondary: #5A5A6E;
      --border-light: #E5E5EC;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 30px rgba(0,0,0,0.05);
      --shadow-lg: 0 16px 40px rgba(0,0,0,0.1);
      --shadow-xl: 0 20px 50px rgba(0,0,0,0.12);
      --radius-xs: 8px;
      --radius-sm: 12px;
      --radius-md: 20px;
      --radius-lg: 30px;
      --radius-full: 50px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", "Segoe UI", system-ui, sans-serif;
      --container-max: 1280px;
      --nav-height: 72px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--background);
      color: var(--text-primary);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      background: transparent;
      transition: all 0.25s ease;
    }

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

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      z-index: 1000;
      transition: box-shadow 0.3s ease, background 0.3s ease;
      border-bottom: 1px solid transparent;
    }

    .header.scrolled {
      box-shadow: var(--shadow-md);
      background: rgba(255,255,255,0.98);
      border-bottom: 1px solid var(--border-light);
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 800;
      font-size: 1.6rem;
      color: var(--secondary);
      letter-spacing: -0.3px;
      transition: opacity 0.2s;
    }
    .logo i {
      color: var(--primary);
      font-size: 2rem;
      margin-right: 2px;
    }
    .logo:hover {
      opacity: 0.85;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2.2rem;
      font-weight: 600;
      font-size: 1rem;
    }

    .nav-links a {
      color: var(--text-secondary);
      position: relative;
      padding: 6px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s ease;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .mobile-toggle {
      display: none;
      background: transparent;
      font-size: 1.8rem;
      color: var(--secondary);
    }

    /* Hero 双栏 */
    .hero {
      padding: calc(var(--nav-height) + 60px) 0 70px;
      display: flex;
      align-items: center;
      gap: 40px;
    }

    .hero-left {
      flex: 1 1 55%;
    }
    .hero-right {
      flex: 1 1 45%;
      position: relative;
      display: flex;
      justify-content: center;
    }

    .hero-badge {
      display: inline-block;
      background: rgba(255,184,0,0.15);
      color: #B47B00;
      padding: 6px 18px;
      border-radius: var(--radius-full);
      font-weight: 600;
      font-size: 0.9rem;
      letter-spacing: 0.3px;
      margin-bottom: 24px;
    }

    h1 {
      font-size: 3.2rem;
      font-weight: 800;
      line-height: 1.3;
      color: var(--secondary);
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      max-width: 500px;
      margin-bottom: 35px;
    }

    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-full);
      font-weight: 700;
      font-size: 1rem;
      letter-spacing: 0.5px;
      box-shadow: 0 10px 18px rgba(232,66,63,0.35);
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 16px 28px rgba(232,66,63,0.5);
      filter: brightness(1.08);
    }

    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      background: transparent;
      padding: 14px 36px;
      border-radius: var(--radius-full);
      font-weight: 700;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      transform: translateY(-2px);
    }

    .hero-cover {
      width: 100%;
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-lg);
    }
    .hero-cover img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }

    .floating-stat {
      position: absolute;
      bottom: 20px;
      right: -10px;
      background: white;
      padding: 10px 18px;
      border-radius: var(--radius-sm);
      box-shadow: var(--shadow-md);
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 0.95rem;
      border-left: 4px solid var(--accent-gold);
    }

    /* 数据徽章 */
    .stats-strip {
      background: white;
      border-radius: var(--radius-md);
      padding: 30px 10px;
      box-shadow: var(--shadow-sm);
      margin: 20px 0 60px;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
      gap: 20px;
    }
    .stat-item i {
      font-size: 2rem;
      color: var(--primary);
      margin-bottom: 10px;
    }
    .stat-number {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.2;
    }
    .stat-label {
      color: var(--text-secondary);
      font-weight: 500;
    }

    /* 区块通用 */
    .section {
      padding: 70px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 800;
      margin-bottom: 18px;
      color: var(--secondary);
    }
    .section-desc {
      color: var(--text-secondary);
      max-width: 600px;
      margin-bottom: 40px;
    }

    /* 亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .feature-card {
      background: white;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-md);
      overflow: hidden;
      transition: transform 0.3s, box-shadow 0.3s;
    }
    .feature-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-lg);
    }
    .feature-img img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
    }
    .feature-content {
      padding: 20px 24px 24px;
    }
    .feature-tag {
      background: #FFEDB3;
      color: #754C00;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.75rem;
      font-weight: 700;
    }

    /* 案例瀑布流 */
    .cases-waterfall {
      columns: 3 280px;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
      background: white;
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
    }
    .case-img-wrap {
      position: relative;
    }
    .case-img-wrap img {
      width: 100%;
      display: block;
    }
    .case-caption {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(transparent, rgba(0,0,0,0.7));
      color: white;
      padding: 30px 20px 16px;
      font-weight: 700;
    }

    /* 方案对比 */
    .plans-row {
      display: flex;
      gap: 24px;
      align-items: stretch;
    }
    .plan-card {
      background: white;
      border-radius: var(--radius-md);
      padding: 32px 24px;
      flex: 1;
      box-shadow: var(--shadow-sm);
      border: 2px solid transparent;
      transition: all 0.3s;
      display: flex;
      flex-direction: column;
    }
    .plan-card.recommended {
      border-color: var(--primary);
      background: #FFF8F8;
      position: relative;
    }
    .badge-popular {
      background: var(--accent-gold);
      color: #1F1F2E;
      padding: 4px 12px;
      border-radius: 20px;
      font-weight: 700;
      font-size: 0.75rem;
      width: fit-content;
      margin-bottom: 12px;
    }

    .plan-price {
      font-size: 2rem;
      font-weight: 800;
      color: var(--secondary);
    }
    .plan-features {
      list-style: none;
      margin: 24px 0;
    }
    .plan-features li {
      margin-bottom: 10px;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-sm);
      padding: 16px 20px;
      border-left: 4px solid var(--primary);
      cursor: pointer;
    }
    .faq-question {
      font-weight: 700;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-secondary);
    }
    .faq-item.open .faq-answer {
      max-height: 150px;
      margin-top: 12px;
    }

    /* CTA */
    .cta-banner {
      background: var(--secondary);
      border-radius: var(--radius-md);
      padding: 60px 20px;
      text-align: center;
      color: white;
    }
    .cta-banner h2 {
      font-size: 2.4rem;
      font-weight: 800;
      margin-bottom: 16px;
    }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: #CBCBD4;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 1024px) {
      .hero { flex-wrap: wrap; }
      .features-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-toggle { display: block; }
      .features-grid, .faq-grid { grid-template-columns: 1fr; }
      .plans-row { flex-direction: column; }
    }