/* roulang page: index */
/* ----- 设计变量 :root ----- */
    :root {
      --primary-orange: #E8452D;
      --primary-orange-hover: #C0392B;
      --secondary-dark: #1E1E24;
      --bg-warm: #F9F7F4;
      --accent-green: #00D68F;
      --neutral-light: #EAE6E1;
      --text-body: #3A3A3E;
      --text-muted: #6B6B6F;
      --text-light: #B0B0B5;
      --white: #FFFFFF;
      --card-shadow: 0 2px 12px rgba(0,0,0,0.04);
      --card-hover-shadow: 0 8px 24px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --transition-smooth: 0.2s ease;
      --container-max: 1200px;
      --grid-gap: 24px;
    }

    /* ----- Reset & Base ----- */
    *, *::before, *::after {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

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

    body {
      font-family: var(--font-heading);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.7;
      letter-spacing: 0.01em;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
    }

    ul {
      list-style: none;
    }

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

    /* 板块通用间距 */
    section {
      padding: 90px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
      .container {
        padding: 0 20px;
      }
    }

    /* 标题装饰线 */
    .section-title {
      text-align: center;
      margin-bottom: 50px;
      font-size: 2rem;
      font-weight: 700;
      color: var(--secondary-dark);
      position: relative;
      padding-bottom: 20px;
    }
    .section-title::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 50px;
      height: 3px;
      background: var(--accent-green);
      border-radius: 2px;
    }

    /* ----- 导航 Header ----- */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,245,0.93);
      backdrop-filter: blur(10px);
      box-shadow: 0 1px 6px rgba(0,0,0,0.02);
      z-index: 50;
      padding: 12px 0;
      transition: box-shadow var(--transition-smooth);
    }
    .header-shadow {
      box-shadow: 0 4px 18px rgba(0,0,0,0.06);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 1.7rem;
      font-weight: 800;
      color: var(--primary-orange);
      display: flex;
      align-items: center;
      gap: 6px;
      letter-spacing: -0.5px;
      background: linear-gradient(135deg, var(--primary-orange), #c02b1a);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .logo i {
      font-size: 1.8rem;
      background: none;
      -webkit-text-fill-color: var(--primary-orange);
      background-clip: unset;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-link {
      font-weight: 500;
      color: var(--secondary-dark);
      transition: color var(--transition-smooth);
      font-size: 15px;
      position: relative;
      padding: 5px 0;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-orange);
      transition: width var(--transition-smooth);
    }
    .nav-link:hover {
      color: var(--primary-orange);
    }
    .nav-link:hover::after {
      width: 100%;
    }
    .btn-nav-cta {
      background: var(--primary-orange);
      color: white;
      padding: 8px 20px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 14px;
      transition: all var(--transition-smooth);
      margin-left: 10px;
    }
    .btn-nav-cta:hover {
      background: var(--primary-orange-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 16px rgba(232,69,45,0.25);
    }
    /* 汉堡菜单 */
    .hamburger {
      display: none;
      font-size: 1.6rem;
      color: var(--secondary-dark);
      cursor: pointer;
      background: none;
      border: none;
    }
    @media (max-width: 1024px) {
      .nav-menu {
        gap: 20px;
      }
    }
    @media (max-width: 768px) {
      .hamburger {
        display: block;
      }
      .nav-menu {
        position: fixed;
        top: 65px;
        left: 0;
        width: 100%;
        background: var(--secondary-dark);
        flex-direction: column;
        align-items: flex-start;
        padding: 25px;
        gap: 20px;
        transform: translateY(-150%);
        transition: transform 0.3s ease-in-out;
        z-index: 45;
        border-radius: 0 0 16px 16px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.2);
      }
      .nav-menu.active {
        transform: translateY(0);
      }
      .nav-link {
        color: white;
        font-size: 16px;
      }
      .btn-nav-cta {
        margin-left: 0;
        width: 100%;
        text-align: center;
        padding: 12px;
        margin-top: 5px;
      }
    }

    /* ----- Hero 首屏 ----- */
    #hero {
      min-height: 92vh;
      display: flex;
      align-items: center;
      justify-content: center;
      background: url('/assets/images/backpic/back-1.webp') center center / cover no-repeat;
      background-attachment: fixed;
      position: relative;
      margin-top: 70px;
      color: white;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(30,30,36,0.75) 20%, rgba(232,69,45,0.2) 100%);
      backdrop-filter: blur(2px);
      z-index: 1;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      text-align: center;
      max-width: 800px;
      padding: 20px;
    }
    .hero-content h1 {
      font-size: 3.2rem;
      font-weight: 800;
      line-height: 1.25;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
      text-shadow: 0 4px 22px rgba(0,0,0,0.5);
    }
    .hero-content .lead {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.9);
      margin-bottom: 35px;
      max-width: 550px;
      margin-left: auto;
      margin-right: auto;
    }
    .hero-btns {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 16px;
    }
    .btn-primary {
      background: var(--primary-orange);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: all var(--transition-smooth);
      border: none;
      display: inline-block;
    }
    .btn-primary:hover {
      background: var(--primary-orange-hover);
      transform: translateY(-3px);
      box-shadow: 0 14px 24px rgba(232,69,45,0.4);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all var(--transition-smooth);
    }
    .btn-secondary:hover {
      background: white;
      color: var(--secondary-dark);
      transform: translateY(-3px);
      box-shadow: 0 8px 18px rgba(255,255,255,0.3);
    }

    @media (max-width: 640px) {
      .hero-content h1 {
        font-size: 2.4rem;
      }
      #hero {
        min-height: 85vh;
        background-attachment: scroll;
      }
    }

    /* ----- Features 核心功能 ----- */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      text-align: center;
      box-shadow: var(--card-shadow);
      transition: all var(--transition-smooth);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--card-hover-shadow);
    }
    .icon-circle {
      width: 60px;
      height: 60px;
      background: rgba(232,69,45,0.08);
      display: flex;
      align-items: center;
      justify-content: center;
      border-radius: 50%;
      margin: 0 auto 20px;
      color: var(--primary-orange);
      font-size: 28px;
    }
    .feature-card h3 {
      margin-bottom: 12px;
      font-weight: 600;
      color: var(--secondary-dark);
    }
    .feature-card p {
      color: var(--text-muted);
      font-size: 14px;
      line-height: 1.7;
    }
    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 520px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }

    /* ----- 场景板块 Scenarios ----- */
    .scenario-item {
      display: flex;
      align-items: center;
      gap: 50px;
      margin-bottom: 70px;
    }
    .scenario-item.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1 1 50%;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: 0 10px 25px rgba(0,0,0,0.06);
    }
    .scenario-text {
      flex: 1 1 50%;
    }
    .scenario-text h3 {
      font-size: 26px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--secondary-dark);
    }
    .scenario-text p {
      color: var(--text-body);
      line-height: 1.8;
    }
    @media (max-width: 768px) {
      .scenario-item, .scenario-item.reverse {
        flex-direction: column;
        gap: 24px;
      }
      .scenario-text h3 {
        font-size: 22px;
      }
    }

    /* ----- 案例卡片 Cases ----- */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 26px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px 22px;
      box-shadow: var(--card-shadow);
      text-align: center;
    }
    .big-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--accent-green);
      line-height: 1.1;
    }
    @media (max-width: 768px) {
      .cases-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 520px) {
      .cases-grid {
        grid-template-columns: 1fr;
      }
    }

    /* ----- 价格卡片 Pricing ----- */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 36px 24px;
      box-shadow: var(--card-shadow);
      text-align: center;
      transition: all var(--transition-smooth);
      border: 2px solid transparent;
    }
    .pricing-card.featured {
      border-color: var(--accent-green);
      box-shadow: 0 0 0 3px rgba(0,214,143,0.15), var(--card-hover-shadow);
    }
    .price {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--secondary-dark);
      margin: 15px 0;
    }
    @media (max-width: 768px) {
      .pricing-grid {
        grid-template-columns: 1fr;
        max-width: 400px;
        margin: 0 auto;
      }
    }

    /* ----- FAQ 折叠 ----- */
    .faq-list {
      max-width: 780px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--neutral-light);
      padding: 18px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--secondary-dark);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-muted);
      padding-right: 30px;
      line-height: 1.7;
    }
    .faq-item.active .faq-answer {
      max-height: 180px;
      margin-top: 10px;
    }
    .faq-item.active .faq-question i {
      transform: rotate(45deg);
    }

    /* ----- CTA Banner ----- */
    .cta-banner {
      background: linear-gradient(135deg, #1E1E24 0%, rgba(232,69,45,0.7) 100%);
      text-align: center;
      border-radius: 20px;
      color: white;
      padding: 65px 30px;
    Gh
    /* Footer */
    .site-footer {
      background: var(--secondary-dark);
      color: var(--text-light);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }