/* roulang page: index */
:root {
      --primary-deep-green: #1A3C34;
      --primary-dark-bg: #0F2922;
      --accent-orange: #F15A24;
      --accent-orange-hover: #D94A1A;
      --gold-accent: #C8A951;
      --bg-warm-white: #FAF9F7;
      --card-bg: #FFFFFF;
      --text-heading: #1E1E1E;
      --text-body: #4A4A4A;
      --text-light: #E0E0E0;
      --text-on-dark: #FFFFFF;
      --border-light: #D0D9D5;
      --bg-light-gray: #F4F6F5;
      --bg-hover: #F9FAF9;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
      --radius-card: 12px;
      --radius-button: 8px;
      --radius-sm: 6px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --transition: 0.25s ease;
      --nav-width: 240px;
      --max-content: 1200px;
    }

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

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm-white);
      color: var(--text-body);
      line-height: 1.7;
      display: flex;
      flex-direction: column;
      min-height: 100vh;
      -webkit-font-smoothing: antialiased;
    }

    /* 桌面侧栏布局 */
    .app-shell {
      display: flex;
      flex: 1;
    }

    /* 左侧导航 */
    .side-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: var(--nav-width);
      height: 100vh;
      background: var(--primary-deep-green);
      display: flex;
      flex-direction: column;
      z-index: 1000;
      box-shadow: 2px 0 15px rgba(0,0,0,0.08);
      padding: 2rem 1.2rem;
      color: white;
      transition: transform 0.3s ease;
    }

    .nav-logo {
      display: flex;
      align-items: center;
      gap: 0.6rem;
      margin-bottom: 3rem;
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: -0.02em;
      color: white;
      text-decoration: none;
      border-left: 3px solid transparent;
      padding-left: 0.5rem;
    }
    .nav-logo span {
      color: var(--accent-orange);
    }
    .nav-links {
      list-style: none;
      flex: 1;
    }
    .nav-links li {
      margin-bottom: 0.8rem;
    }
    .nav-links a {
      display: block;
      color: rgba(255,255,255,0.8);
      text-decoration: none;
      padding: 0.7rem 0.8rem;
      border-left: 3px solid transparent;
      font-weight: 500;
      transition: all var(--transition);
      border-radius: 0 6px 6px 0;
      font-size: 1rem;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-orange);
      background: rgba(255,255,255,0.06);
      border-left-color: var(--accent-orange);
    }
    .nav-cta {
      margin-top: auto;
      background: var(--accent-orange);
      color: white;
      border: none;
      padding: 0.8rem 1.2rem;
      border-radius: var(--radius-button);
      font-weight: 700;
      cursor: pointer;
      text-align: center;
      transition: background var(--transition), transform 0.2s;
      font-size: 1rem;
      box-shadow: 0 4px 10px rgba(241,90,36,0.3);
    }
    .nav-cta:hover {
      background: var(--accent-orange-hover);
    }

    /* 主内容区 */
    .main-content {
      margin-left: var(--nav-width);
      flex: 1;
      width: calc(100% - var(--nav-width));
      background: var(--bg-warm-white);
    }

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 56px;
      background: var(--primary-deep-green);
      z-index: 999;
      align-items: center;
      justify-content: space-between;
      padding: 0 1.2rem;
      color: white;
    }
    .hamburger {
      background: none;
      border: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
      width: 44px;
      height: 44px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .mobile-logo {
      font-weight: 700;
      font-size: 1.2rem;
      color: white;
    }

    /* 抽屉菜单 */
    .drawer-overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.5);
      z-index: 998;
      display: none;
    }
    .drawer {
      position: fixed;
      top: 0;
      left: 0;
      width: 80%;
      max-width: 300px;
      height: 100vh;
      background: var(--primary-deep-green);
      z-index: 1001;
      transform: translateX(-100%);
      transition: transform 0.3s ease;
      padding: 2rem 1.2rem;
      display: flex;
      flex-direction: column;
    }
    .drawer.open {
      transform: translateX(0);
    }
    .drawer-close {
      align-self: flex-end;
      background: none;
      border: none;
      color: white;
      font-size: 2rem;
      cursor: pointer;
    }

    .container {
      max-width: var(--max-content);
      margin: 0 auto;
      padding: 0 40px;
    }

    section {
      padding: 100px 0;
    }

    /* 斜向分割线 */
    .section-divider {
      height: 40px;
      background: linear-gradient(175deg, var(--bg-warm-white) 50%, var(--primary-deep-green) 50%);
    }
    .section-divider-reverse {
      height: 40px;
      background: linear-gradient(-5deg, var(--bg-warm-white) 50%, var(--primary-deep-green) 50%);
    }

    h1, h2, h3 {
      font-family: var(--font-title);
      color: var(--text-heading);
      letter-spacing: -0.02em;
    }
    h1 {
      font-size: 3.2rem;
      line-height: 1.2;
      font-weight: 800;
    }
    h2 {
      font-size: 2.4rem;
      font-weight: 700;
      margin-bottom: 1.2rem;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }

    .btn {
      display: inline-block;
      padding: 0.9rem 2.2rem;
      border-radius: var(--radius-button);
      font-weight: 700;
      text-decoration: none;
      transition: all var(--transition);
      cursor: pointer;
      border: 2px solid transparent;
      font-size: 1rem;
      text-align: center;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      border-color: var(--accent-orange);
    }
    .btn-primary:hover {
      background: var(--accent-orange-hover);
      border-color: var(--accent-orange-hover);
    }
    .btn-outline {
      background: transparent;
      border-color: var(--primary-deep-green);
      color: var(--primary-deep-green);
    }
    .btn-outline:hover {
      background: var(--primary-deep-green);
      color: white;
    }
    .btn-light {
      background: white;
      color: var(--primary-deep-green);
      border-color: white;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #1A3C34 0%, #0F2922 100%);
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.35;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      color: white;
      max-width: 700px;
    }
    .hero h1, .hero h2 {
      color: white;
    }
    .hero-buttons {
      display: flex;
      gap: 1.2rem;
      margin-top: 2rem;
      flex-wrap: wrap;
    }

    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      padding: 2rem;
      transition: all var(--transition);
      border-left: 4px solid var(--accent-orange);
    }
    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
      border-left-width: 6px;
    }
    .solution-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
      margin-top: 2rem;
    }
    .solution-grid .card:last-child {
      grid-column: span 2;
      max-width: 50%;
      justify-self: center;
    }

    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 2rem;
    }
    .testimonial-card {
      background: var(--bg-light-gray);
      padding: 2rem;
      border-radius: var(--radius-card);
    }
    blockquote {
      font-style: italic;
      margin: 1rem 0;
    }

    .faq-item {
      background: white;
      border-bottom: 1px solid var(--border-light);
      overflow: hidden;
    }
    .faq-question {
      padding: 1.2rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: white;
      transition: background var(--transition);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding: 0 1.2rem;
      background: white;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 0 1.2rem 1.2rem;
    }

    .stats {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 2rem;
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary-deep-green);
    }

    footer {
      background: var(--primary-deep-green);
      color: var(--text-light);
      padding: 2rem 0;
    }

    @media (max-width: 1024px) {
      .side-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        padding-top: 56px;
      }
      .container {
        padding: 0 24px;
      }
      h1 {
        font-size: 2.4rem;
      }
      h2 {
        font-size: 2rem;
      }
      .solution-grid {
        grid-template-columns: 1fr;
      }
      .solution-grid .card:last-child {
        grid-column: span 1;
        max-width: 100%;
      }
    }

    @media (max-width: 768px) {
      .hero-buttons .btn {
        width: 100%;
      }
      section {
        padding: 70px 0;
      }
    }