/* roulang page: index */
:root {
      --primary: #E63946;
      --primary-dark: #c62d39;
      --secondary: #1D1D1F;
      --accent: #F4A261;
      --accent-light: #fbbf8c;
      --bg-light: #F8F9FA;
      --bg-white: #FFFFFF;
      --text-main: #1D1D1F;
      --text-secondary: #6B7280;
      --text-light: #9CA3AF;
      --border-light: #E5E7EB;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-md: 0 10px 25px rgba(0,0,0,0.1);
      --shadow-lg: 0 20px 40px rgba(0,0,0,0.12);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: var(--font-sans);
      color: var(--text-main);
      background-color: var(--bg-white);
      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: opacity 0.2s ease;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 500;
      transition: all 0.25s ease;
      border: none;
      outline: none;
    }
    .container {
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }
    /* 导航 */
    .nav-bar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: transparent;
      transition: background 0.3s ease, backdrop-filter 0.3s ease, box-shadow 0.3s ease;
      padding: 16px 0;
    }
    .nav-bar.scrolled {
      background: rgba(29, 29, 31, 0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
      padding: 12px 0;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: #fff;
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 0.5px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #fff;
      font-weight: 700;
      font-size: 1.2rem;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-nav {
      background: var(--primary);
      color: #fff;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 4px 10px rgba(230, 57, 70, 0.3);
    }
    .btn-nav:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: #fff;
      border-radius: 2px;
      transition: 0.2s;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: 0;
        height: 100vh;
        width: 280px;
        background: var(--secondary);
        flex-direction: column;
        padding: 80px 32px 40px;
        gap: 28px;
        transform: translateX(100%);
        transition: transform 0.3s ease;
        box-shadow: -10px 0 30px rgba(0,0,0,0.3);
      }
      .nav-links.open {
        transform: translateX(0);
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
      .nav-links a {
        font-size: 1.2rem;
      }
      .btn-nav {
        width: 100%;
        justify-content: center;
        margin-top: 12px;
      }
    }
    /* Hero */
    .hero {
      height: 90vh;
      min-height: 700px;
      position: relative;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(0,0,0,0.1) 0%, rgba(29,29,31,0.7) 90%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      color: #fff;
      margin-top: -20px;
    }
    .hero h1 {
      font-size: clamp(2.5rem, 5vw, 3.8rem);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero h1 .highlight {
      color: var(--primary);
      background: linear-gradient(135deg, #E63946, #f14e5b);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 36px;
      max-width: 560px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: #fff;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1.1rem;
      box-shadow: 0 8px 18px rgba(230,57,70,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }
    .btn-outline {
      border: 2px solid rgba(255,255,255,0.9);
      color: #fff;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
      border-color: #fff;
    }
    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
      .hero {
        height: auto;
        min-height: 90vh;
        padding: 120px 0 80px;
      }
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-secondary);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 48px;
    }
    /* 核心优势 错落布局 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
      max-width: 1000px;
      margin: 0 auto;
    }
    .feature-card {
      background: var(--bg-white);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .feature-card h3 {
      font-size: 1.4rem;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .feature-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
    }
    .feature-card:nth-child(3) {
      grid-column: span 2;
      justify-self: center;
      max-width: 480px;
    }
    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
      .feature-card:nth-child(3) {
        grid-column: span 1;
        max-width: 100%;
      }
    }
    /* 场景 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
    }
    .scenario-img img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 16 / 10;
    }
    .scenario-text {
      flex: 1;
    }
    .scenario-text h3 {
      font-size: 1.8rem;
      font-weight: 600;
      margin-bottom: 14px;
    }
    .scenario-text p {
      color: var(--text-secondary);
      margin-bottom: 16px;
    }
    .tag-list {
      display: flex;
      flex-wrap: wrap;
      gap: 10px;
    }
    .tag {
      background: #f1f1f1;
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 0.85rem;
      color: var(--text-main);
    }
    @media (max-width: 768px) {
      .scenario-row, .scenario-row.reverse {
        flex-direction: column;
        gap: 28px;
      }
    }
    /* 数据卡片 */
    .cases-bg {
      background: #F3F4F6;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      text-align: center;
    }
    .stat-card {
      background: #fff;
      padding: 32px;
      border-radius: var(--radius-card);
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
    }
    .stat-unit {
      font-size: 1rem;
      color: var(--text-secondary);
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 价格 */
    .pricing-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 28px;
      justify-content: center;
    }
    .pricing-card {
      background: #fff;
      border-radius: var(--radius-card);
      padding: 36px 28px;
      box-shadow: var(--shadow-sm);
      flex: 1 1 250px;
      max-width: 300px;
      display: flex;
      flex-direction: column;
      border: 2px solid transparent;
      transition: 0.25s;
    }
    .pricing-card.recommended {
      border-color: var(--primary);
      position: relative;
      box-shadow: var(--shadow-md);
    }
    .badge {
      position: absolute;
      top: 16px;
      right: 16px;
      background: var(--accent);
      color: #000;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    .price {
      font-size: 2.4rem;
      font-weight: 700;
      margin: 16px 0;
    }
    .feature-list {
      list-style: none;
      margin: 20px 0;
    }
    .feature-list li {
      padding: 8px 0;
      color: var(--text-secondary);
    }
    .btn-pricing {
      margin-top: auto;
      padding: 12px 20px;
      border-radius: var(--radius-btn);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      text-align: left;
      padding: 18px 8px;
      font-weight: 500;
      font-size: 1rem;
      display: flex;
      justify-content: space-between;
      border: none;
      color: var(--text-main);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 8px;
      color: var(--text-secondary);
    }
    .faq-answer.open {
      max-height: 200px;
      padding-bottom: 16px;
    }
    /* CTA 尾屏 */
    .cta-section {
      background: var(--secondary);
      color: #fff;
      text-align: center;
    }
    .cta-section h2 {
      font-size: 2.4rem;
      margin-bottom: 12px;
    }
    /* 页脚 */
    .footer {
      background: #1a1a1c;
      color: #ccc;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }
    .copyright {
      margin-top: 30px;
      text-align: center;
      font-size: 0.85rem;
      color: #888;
    }