/* roulang page: index */
:root {
      --primary: #F15A24;
      --primary-dark: #D94A1A;
      --secondary: #1E1E24;
      --bg-warm: #F7F5F2;
      --accent-green: #A3E635;
      --text-main: #1A1A1A;
      --text-secondary: #5C5C5C;
      --text-muted: #949494;
      --white: #FFFFFF;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04);
      --card-hover-shadow: 0 12px 32px rgba(241,90,36,0.12);
      --radius-card: 16px;
      --radius-btn: 10px;
      --radius-small: 12px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
      --font-number: 'DIN Alternate', 'PingFang SC', sans-serif;
      --nav-width: 240px;
      --transition: all 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm);
      color: var(--text-main);
      margin: 0;
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4, .h1, .h2, .h3 {
      font-family: var(--font-heading);
      font-weight: 600;
      color: var(--secondary);
    }

    h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
    }
    h2 {
      font-size: 34px;
      font-weight: 600;
      margin-bottom: 1.5rem;
    }
    h3 {
      font-size: 22px;
      font-weight: 600;
    }

    a {
      color: var(--primary);
      transition: var(--transition);
    }
    a:hover {
      color: var(--primary-dark);
      text-decoration: none;
    }

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

    /* 自定义容器，右侧留出导航宽度 */
    .main-content {
      margin-left: var(--nav-width);
      position: relative;
      background: var(--bg-warm);
    }

    /* ---------- 左侧竖向导航 ---------- */
    .side-nav {
      position: fixed;
      left: 0;
      top: 0;
      width: var(--nav-width);
      height: 100vh;
      background-color: var(--secondary);
      color: white;
      display: flex;
      flex-direction: column;
      z-index: 100;
      box-shadow: 2px 0 15px rgba(0,0,0,0.08);
      padding: 2rem 1.5rem;
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 3rem;
      padding-bottom: 1.5rem;
      border-bottom: 1px solid rgba(255,255,255,0.15);
    }
    .logo-icon {
      font-size: 1.8rem;
      color: var(--primary);
      display: flex;
      align-items: center;
    }
    .logo-text {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: 1px;
      color: white;
    }

    .nav-links {
      list-style: none;
      margin: 0;
      padding: 0;
      flex: 1;
    }
    .nav-links li {
      margin-bottom: 0.5rem;
    }
    .nav-links a {
      display: flex;
      align-items: center;
      color: rgba(255,255,255,0.8);
      text-decoration: none;
      padding: 0.75rem 1rem;
      border-left: 4px solid transparent;
      font-size: 15px;
      font-weight: 500;
      transition: var(--transition);
      border-radius: 0 6px 6px 0;
      margin-left: -1.5rem;
      padding-left: 2rem;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: white;
      background-color: rgba(255,255,255,0.05);
      border-left-color: var(--primary);
    }
    .nav-links a.active {
      font-weight: 600;
      border-left-width: 6px;
    }

    .nav-footer {
      margin-top: auto;
      font-size: 0.85rem;
      color: rgba(255,255,255,0.6);
    }
    .nav-footer .slogan {
      font-weight: 500;
      margin-bottom: 0.5rem;
      color: rgba(255,255,255,0.9);
    }

    /* 移动端顶部导航 */
    .mobile-header {
      display: none;
      background: var(--secondary);
      color: white;
      padding: 0 1.25rem;
      height: 60px;
      align-items: center;
      justify-content: space-between;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 110;
      box-shadow: 0 2px 10px rgba(0,0,0,0.2);
    }
    .mobile-logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.3rem;
    }
    .hamburger {
      background: none;
      border: none;
      color: white;
      font-size: 1.6rem;
      cursor: pointer;
      padding: 8px;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 60px;
      left: 0;
      width: 100%;
      background: var(--secondary);
      flex-direction: column;
      padding: 1.5rem;
      z-index: 105;
      box-shadow: 0 8px 20px rgba(0,0,0,0.25);
    }
    .mobile-menu a {
      color: white;
      padding: 0.8rem 0;
      border-bottom: 1px solid rgba(255,255,255,0.1);
      text-decoration: none;
      font-size: 16px;
    }

    /* ---------- 板块通用 ---------- */
    .section {
      padding: 5rem 2.5rem;
      max-width: 1200px;
      margin: 0 auto;
    }
    .section-title {
      margin-bottom: 2.5rem;
      position: relative;
    }
    .section-title h2 {
      margin-bottom: 0.5rem;
      color: var(--secondary);
    }
    .section-title::after {
      content: '';
      display: block;
      width: 60px;
      height: 4px;
      background: var(--primary);
      margin-top: 0.5rem;
      border-radius: 2px;
    }

    /* Hero */
    .hero {
      height: 100vh;
      min-height: 600px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
      color: white;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(241,90,36,0.75) 0%, rgba(30,30,36,0.8) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      padding: 2rem;
    }
    .hero h1 {
      color: white;
      font-size: 52px;
      margin-bottom: 1.25rem;
    }
    .hero-sub {
      font-size: 20px;
      opacity: 0.9;
      margin-bottom: 2rem;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--primary), #D94A1A);
      border: none;
      color: white;
      padding: 14px 34px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      box-shadow: 0 6px 18px rgba(241,90,36,0.3);
      display: inline-block;
      text-decoration: none;
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(163,230,53,0.25);
      background: linear-gradient(135deg, #FF6B38, #F15A24);
      color: white;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
      text-decoration: none;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
      color: white;
    }

    /* 卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 2rem 1.8rem;
      box-shadow: var(--card-shadow);
      transition: var(--transition);
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--card-hover-shadow);
    }
    .card-icon {
      font-size: 2.4rem;
      color: var(--primary);
      margin-bottom: 1.2rem;
    }
    .service-card h3 {
      margin-bottom: 0.8rem;
    }
    .feature-list {
      list-style: none;
      margin: 1rem 0 0;
      padding: 0;
    }
    .feature-list li {
      display: flex;
      align-items: flex-start;
      gap: 8px;
      font-size: 14px;
      color: var(--text-secondary);
      margin-bottom: 0.5rem;
    }
    .feature-list li i {
      color: var(--accent-green);
      font-size: 0.9rem;
      margin-top: 4px;
    }

    /* 数据徽章 */
    .stats-bar {
      display: flex;
      justify-content: space-between;
      gap: 1.5rem;
      flex-wrap: wrap;
    }
    .stat-item {
      background: var(--white);
      border-radius: var(--radius-small);
      padding: 1.8rem 1.5rem;
      text-align: center;
      flex: 1;
      min-width: 140px;
      box-shadow: var(--card-shadow);
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 44px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-label {
      color: var(--text-secondary);
      font-size: 15px;
      margin-top: 0.4rem;
    }

    /* 案例交替 */
    .case-row {
      display: flex;
      align-items: center;
      gap: 2.5rem;
      margin-bottom: 3.5rem;
    }
    .case-row.reverse {
      flex-direction: row-reverse;
    }
    .case-text {
      flex: 1;
    }
    .case-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--card-shadow);
    }
    .case-badge {
      background: var(--accent-green);
      color: #1E1E24;
      font-weight: 700;
      padding: 0.25rem 1rem;
      border-radius: 20px;
      font-size: 14px;
      display: inline-block;
      margin: 0.5rem 0;
    }

    /* 步骤条 */
    .steps-container {
      display: flex;
      justify-content: space-between;
      position: relative;
      gap: 1rem;
    }
    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }
    .step-circle {
      width: 56px;
      height: 56px;
      border-radius: 50%;
      background: white;
      border: 3px solid var(--primary);
      color: var(--primary);
      font-weight: 700;
      font-size: 1.5rem;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 1rem;
    }
    .step-line {
      position: absolute;
      top: 28px;
      left: 70%;
      width: 60%;
      height: 2px;
      background: #ddd;
      z-index: -1;
    }

    /* FAQ */
    .faq-group {
      margin-bottom: 2rem;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-small);
      margin-bottom: 10px;
      box-shadow: var(--card-shadow);
    }
    .faq-question {
      padding: 1.2rem 1.8rem;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--secondary);
    }
    .faq-answer {
      padding: 0 1.8rem 1.2rem;
      color: var(--text-secondary);
      display: none;
    }

    /* 联系表单 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2.5rem;
      background: #F3F0EC;
      padding: 2.5rem;
      border-radius: var(--radius-card);
    }
    .form-input {
      width: 100%;
      padding: 0.9rem;
      border: 1px solid #ddd;
      border-radius: 8px;
      margin-bottom: 1rem;
      font-family: inherit;
    }
    .form-input:focus {
      border-color: var(--primary);
      outline: none;
    }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: rgba(255,255,255,0.75);
      padding: 2.5rem;
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 2rem;
      margin-left: var(--nav-width);
    }
    .footer a {
      color: white;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .side-nav {
        display: none;
      }
      .mobile-header {
        display: flex;
      }
      .main-content, .footer {
        margin-left: 0;
      }
      .section {
        padding: 3rem 1.5rem;
      }
      .card-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .stats-bar {
        grid-template-columns: repeat(2,1fr);
      }
    }
    @media (max-width: 640px) {
      .card-grid {
        grid-template-columns: 1fr;
      }
      .case-row, .case-row.reverse {
        flex-direction: column;
      }
      .contact-grid {
        grid-template-columns: 1fr;
      }
      .steps-container {
        flex-direction: column;
      }
      .step-line {
        display: none;
      }
      h1 {
        font-size: 36px;
      }
    }