/* roulang page: index */
:root {
      --primary: #0BBF64;
      --primary-dark: #0AA65A;
      --primary-gradient: linear-gradient(135deg, #0BBF64 0%, #00D2A0 100%);
      --accent: #FFD600;
      --ink-dark: #1A1D20;
      --ink-mid: #5A6A72;
      --bg-light: #F5FAF8;
      --bg-white: #FFFFFF;
      --border-subtle: #E8EDEA;
      --radius-card: 12px;
      --radius-btn: 50px;
      --radius-input: 8px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 10px 28px rgba(0,0,0,0.08);
      --transition-smooth: 0.25s ease-out;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
      -webkit-text-size-adjust: 100%;
    }

    body {
      font-family: var(--font-body);
      line-height: 1.7;
      background: var(--bg-white);
      color: var(--ink-dark);
      -webkit-font-smoothing: antialiased;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      cursor: pointer;
      border: none;
      background: none;
      font-family: inherit;
      outline: none;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: var(--bg-white);
      z-index: 100;
      display: flex;
      align-items: center;
      transition: box-shadow var(--transition-smooth), border var(--transition-smooth);
      border-bottom: 1px solid transparent;
    }
    .site-header.scrolled {
      box-shadow: 0 4px 12px rgba(0,0,0,0.02);
      border-bottom: 1px solid var(--border-subtle);
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .logo-icon {
      width: 44px;
      height: 44px;
      background: var(--primary-gradient);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 20px;
      font-weight: bold;
      color: white;
    }
    .logo-text {
      font-family: var(--font-title);
      font-weight: 650;
      font-size: 20px;
      letter-spacing: -0.3px;
      color: var(--ink-dark);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-menu a {
      font-size: 15px;
      font-weight: 500;
      color: var(--ink-mid);
      transition: color var(--transition-smooth);
    }
    .nav-menu a:hover {
      color: var(--primary-dark);
    }
    .btn-capsule {
      padding: 10px 28px;
      background: var(--primary);
      color: var(--bg-white) !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background 0.25s, transform 0.2s, box-shadow 0.2s;
      display: inline-block;
      background: var(--primary-gradient);
      box-shadow: 0 2px 10px rgba(11,191,100,0.25);
    }
    .btn-capsule:hover {
      background: linear-gradient(135deg, #0AA65A, #00C299);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(11,191,100,0.3);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      width: 30px;
      background: transparent;
    }
    .hamburger span {
      width: 100%;
      height: 2px;
      background: var(--ink-dark);
      border-radius: 4px;
      transition: 0.2s;
    }
    .mobile-nav {
      display: none;
    }

    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .mobile-nav.active {
        display: flex;
        flex-direction: column;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        padding: 24px;
        box-shadow: 0 12px 24px rgba(0,0,0,0.04);
        gap: 20px;
        list-style: none;
        z-index: 99;
      }
      .mobile-nav a {
        font-size: 18px;
        font-weight: 500;
      }
    }

    /* hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding: 100px 0 60px;
      background: var(--bg-white);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 6fr 4fr;
      gap: 48px;
      align-items: center;
    }
    .hero-left h1 {
      font-family: var(--font-title);
      font-size: 44px;
      font-weight: 700;
      letter-spacing: -0.5px;
      line-height: 1.25;
      color: var(--ink-dark);
    }
    .hero-sub {
      font-size: 18px;
      color: var(--ink-mid);
      margin: 20px 0 32px;
    }
    .hero-buttons {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    .btn-outline {
      border: 1.5px solid var(--primary);
      color: var(--primary-dark);
      padding: 10px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background 0.2s, color 0.2s;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(11,191,100,0.08);
      border-color: var(--primary-dark);
      color: #0AA65A;
    }
    .hero-right {
      position: relative;
      display: flex;
      justify-content: center;
    }
    .floating-media {
      border-radius: 28px;
      overflow: hidden;
      box-shadow: 0 18px 36px rgba(0,0,0,0.06);
      animation: float 4s ease-in-out infinite;
    }
    @keyframes float {
      0% { transform: translateY(0); }
      50% { transform: translateY(-10px); }
      100% { transform: translateY(0); }
    }

    section {
      padding: 90px 0;
    }

    .section-title h2 {
      font-family: var(--font-title);
      font-size: 31px;
      font-weight: 600;
      letter-spacing: -0.3px;
      margin-bottom: 14px;
    }
    .section-desc {
      font-size: 17px;
      color: var(--ink-mid);
      max-width: 640px;
      margin-bottom: 48px;
    }

    /* 功能区块错位栅格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
      margin-top: 30px;
    }
    .features-grid .feature-card:nth-child(4),
    .features-grid .feature-card:nth-child(5) {
      grid-column: span 2;
    }
    .feature-card {
      background: var(--bg-light);
      padding: 28px 24px;
      border-radius: var(--radius-card);
      transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
      box-shadow: var(--shadow-card);
    }
    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 56px;
      height: 56px;
      background: rgba(11,191,100,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary-dark);
      font-size: 28px;
    }
    .feature-card h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 8px;
    }

    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
      .features-grid .feature-card:nth-child(4),
      .features-grid .feature-card:nth-child(5) {
        grid-column: span 1;
      }
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-left h1 { font-size: 34px; }
    }

    /* 场景滚动 */
    .scroll-row {
      display: flex;
      overflow-x: auto;
      gap: 20px;
      padding-bottom: 24px;
      scroll-snap-type: x mandatory;
    }
    .scene-card {
      flex: 0 0 290px;
      background: white;
      border-radius: 16px;
      box-shadow: var(--shadow-card);
      scroll-snap-align: start;
      transition: transform 0.2s;
    }
    .scene-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .scene-img {
      height: 180px;
      background-size: cover;
      border-radius: 16px 16px 0 0;
    }
    .scene-content {
      padding: 16px;
    }
    .progress-line {
      height: 3px;
      background: var(--primary-gradient);
      width: 100%;
      margin-top: 12px;
      border-radius: 2px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--bg-light);
      padding: 28px;
      border-radius: var(--radius-card);
    }
    .big-number {
      font-size: 34px;
      font-weight: 700;
      color: var(--primary);
    }

    @media (max-width: 768px) {
      .cases-grid { grid-template-columns: 1fr; }
    }

    /* faq */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 0;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-subtle);
    }
    .faq-question {
      width: 100%;
      text-align: left;
      padding: 18px 4px;
      font-size: 18px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: transparent;
      transition: color 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      color: var(--ink-mid);
    }
    .faq-item.open .faq-answer {
      max-height: 120px;
      padding-bottom: 18px;
    }

    /* cta gradient */
    .cta-fullwidth {
      background: var(--primary-gradient);
      padding: 80px 0;
      text-align: center;
      color: white;
      border-radius: 0;
    }
    .cta-fullwidth h2 {
      font-size: 36px;
    }
    .btn-white {
      background: white;
      color: #0AA65A;
      padding: 12px 32px;
      border-radius: 50px;
      font-weight: 700;
    }

    footer {
      background: #f5f7f6;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr 0.8fr 0.8fr;
      gap: 30px;
      margin-bottom: 28px;
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 520px) {
      .footer-grid { grid-template-columns: 1fr; }
    }