/* roulang page: index */
:root {
      --primary-orange: #F15A24;
      --primary-deep-green: #1B3A2D;
      --bg-warm-white: #FAF7F2;
      --card-white: #FFFFFF;
      --card-light-milk: #FFF9F0;
      --text-dark: #2C2C2C;
      --text-mid: #6B6B6B;
      --accent-gold: #F7B32B;
      --success-green: #2E7D32;
      --border-light: #D0D9D4;
      --border-card: #E8EDEA;
      --shadow-sm: 0 4px 20px rgba(27,58,45,0.06);
      --shadow-hover: 0 8px 30px rgba(241,90,36,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-number: 'DIN Alternate', 'PingFang SC', sans-serif;
      --nav-width: 220px;
      --transition-default: all 0.25s ease;
    }

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

    body {
      font-family: var(--font-title);
      background-color: var(--bg-warm-white);
      color: var(--text-dark);
      line-height: 1.75;
      font-weight: 400;
      display: flex;
      min-height: 100vh;
      overflow-x: hidden;
    }

    /* 左侧固定导航 */
    .side-nav {
      width: var(--nav-width);
      height: 100vh;
      position: fixed;
      left: 0;
      top: 0;
      background-color: var(--primary-deep-green);
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      padding: 2rem 1.5rem;
      z-index: 100;
      box-shadow: 2px 0 15px rgba(0,0,0,0.08);
    }

    .logo-area {
      margin-bottom: 2.5rem;
    }

    .logo-text {
      font-size: 28px;
      font-weight: 700;
      color: #ffffff;
      letter-spacing: 2px;
      line-height: 1.2;
    }

    .logo-underline {
      width: 40px;
      height: 3px;
      background-color: var(--primary-orange);
      margin-top: 8px;
      border-radius: 2px;
    }

    .nav-links {
      display: flex;
      flex-direction: column;
      gap: 8px;
      margin-top: 1rem;
    }

    .nav-link {
      color: rgba(255,255,255,0.75);
      text-decoration: none;
      font-weight: 500;
      font-size: 16px;
      padding: 0.6rem 0.8rem;
      border-radius: 6px;
      transition: var(--transition-default);
      display: flex;
      align-items: center;
      position: relative;
      border-left: 4px solid transparent;
    }

    .nav-link i {
      margin-right: 10px;
      width: 20px;
      text-align: center;
    }

    .nav-link:hover {
      color: #ffffff;
      background-color: rgba(255,255,255,0.08);
      border-left: 4px solid var(--primary-orange);
    }

    .nav-link.active {
      color: #ffffff;
      border-left: 4px solid var(--primary-orange);
      background-color: rgba(241,90,36,0.15);
    }

    .social-icons {
      display: flex;
      gap: 16px;
      margin-top: auto;
      padding-top: 2rem;
    }

    .social-icons a {
      color: rgba(255,255,255,0.65);
      font-size: 20px;
      transition: var(--transition-default);
    }

    .social-icons a:hover {
      color: var(--primary-orange);
      transform: translateY(-2px);
    }

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

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 60px;
      background-color: var(--primary-deep-green);
      z-index: 99;
      align-items: center;
      justify-content: space-between;
      padding: 0 1.5rem;
      box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    }

    .mobile-logo {
      font-size: 22px;
      font-weight: 700;
      color: #fff;
    }

    .hamburger {
      font-size: 24px;
      color: #fff;
      background: none;
      border: none;
      cursor: pointer;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 60px;
      left: 0;
      width: 100%;
      background-color: var(--primary-deep-green);
      flex-direction: column;
      padding: 1rem 1.5rem;
      z-index: 98;
      box-shadow: 0 8px 15px rgba(0,0,0,0.2);
    }

    .mobile-menu a {
      color: rgba(255,255,255,0.8);
      padding: 0.8rem 0;
      border-bottom: 1px solid rgba(255,255,255,0.1);
      text-decoration: none;
      font-weight: 500;
      display: block;
    }

    .section {
      padding: 80px 0;
    }

    .container-custom {
      max-width: 1100px;
      margin: 0 auto;
      padding: 0 2rem;
    }

    h2 {
      font-family: var(--font-title);
      font-weight: 700;
      color: var(--text-dark);
      font-size: 32px;
      margin-bottom: 1.5rem;
      display: flex;
      align-items: center;
    }

    .title-decor {
      width: 4px;
      height: 36px;
      background-color: var(--primary-orange);
      margin-right: 16px;
      border-radius: 2px;
    }

    /* Hero */
    #hero {
      background: linear-gradient(135deg, #1B3A2D 0%, #F15A24 100%);
      min-height: 90vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }

    .hero-texture {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: radial-gradient(circle at 20% 50%, rgba(255,255,255,0.05) 1px, transparent 1px);
      background-size: 40px 40px;
      pointer-events: none;
    }

    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
    }

    .hero-left {
      flex: 1;
      color: #fff;
    }

    .hero-left h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.2rem;
      text-shadow: 0 4px 12px rgba(0,0,0,0.2);
    }

    .hero-left p {
      font-size: 18px;
      opacity: 0.9;
      max-width: 560px;
      margin-bottom: 2rem;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary-orange);
      color: #fff;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition-default);
      border: none;
      display: inline-block;
    }

    .btn-primary:hover {
      background: #D94A1A;
      transform: translateY(-2px);
      box-shadow: 0 10px 20px rgba(241,90,36,0.3);
      color: #fff;
    }

    .btn-outline {
      background: transparent;
      border: 2px solid #fff;
      color: #fff;
      padding: 12px 30px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition-default);
    }

    .btn-outline:hover {
      background: #fff;
      color: var(--primary-deep-green);
    }

    .hero-right img {
      width: 420px;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.25);
      border: 2px solid rgba(255,255,255,0.2);
    }

    /* 卡片通用 */
    .card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-card);
      transition: var(--transition-default);
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .service-icon {
      font-size: 48px;
      color: var(--primary-orange);
      margin-bottom: 20px;
    }

    .text-link {
      color: var(--primary-orange);
      font-weight: 600;
      text-decoration: none;
    }

    /* 数据徽章 */
    .stat-number {
      font-family: var(--font-number);
      font-size: 42px;
      font-weight: 700;
      color: var(--primary-orange);
    }

    .bg-light-milk {
      background-color: var(--card-light-milk);
    }

    .case-img {
      width: 280px;
      height: 200px;
      object-fit: cover;
      border-radius: 12px;
    }

    .tag {
      background: #E8EDEA;
      color: #1B3A2D;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
    }

    .accordion-item {
      background: #E8EDEA;
      border-radius: 8px;
      margin-bottom: 12px;
    }

    .accordion-title {
      font-weight: 600;
      color: #1B3A2D;
      padding: 16px 20px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }

    .cta-section {
      background: linear-gradient(135deg, #F15A24, #F7B32B);
      padding: 80px 0;
      text-align: center;
      color: #fff;
    }

    .footer {
      background: #1B3A2D;
      color: rgba(255,255,255,0.7);
      padding: 50px 0 20px;
    }

    @media (max-width: 1024px) {
      .side-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content {
        margin-left: 0;
        width: 100%;
        padding-top: 60px;
      }
      .hero-right img {
        width: 300px;
      }
    }

    @media (max-width: 640px) {
      .hero-left h1 {
        font-size: 28px;
      }
      .section {
        padding: 60px 0;
      }
      .hero-right img {
        width: 100%;
        margin-top: 20px;
      }
    }