/* roulang page: index */
:root {
      --color-primary: #0F2B1D;
      --color-accent: #C8A96E;
      --color-highlight: #E85D04;
      --color-bg: #F7F5F0;
      --color-text: #1E1E1E;
      --color-text-secondary: #5C5C5C;
      --color-white: #FFFFFF;
      --color-border: #D9D9D9;
      --radius-card: 12px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 28px rgba(0,0,0,0.08);
      --transition-smooth: 0.3s ease;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'DIN Alternate', 'Bebas Neue', 'PingFang SC', sans-serif;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--color-bg);
      color: var(--color-text);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

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

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

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

    button, input, textarea {
      font-family: inherit;
      outline: none;
    }

    /* 标题字体 */
    h1, h2, h3, .font-title {
      font-family: var(--font-title);
      font-weight: 700;
      letter-spacing: 0.5px;
    }

    h2 {
      font-size: 2.25rem;
      font-weight: 600;
      margin-bottom: 1rem;
    }

    h3 {
      font-size: 1.5rem;
      font-weight: 500;
      margin-bottom: 0.5rem;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(12px);
      z-index: 999;
      transition: box-shadow 0.25s ease;
    }

    #header.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 16px 24px;
    }

    .logo {
      font-family: var(--font-title);
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--color-primary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 1px;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: linear-gradient(135deg, var(--color-primary), #1c3f2b);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--color-accent);
      font-size: 18px;
      font-weight: 700;
      box-shadow: 0 2px 8px rgba(15,43,29,0.2);
    }

    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-menu a {
      font-weight: 500;
      color: var(--color-text);
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }

    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--color-primary);
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 3px;
      background: var(--color-accent);
      border-radius: 4px;
      transition: width 0.25s ease;
    }

    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }

    .btn-nav {
      background: var(--color-highlight);
      color: white;
      padding: 10px 24px;
      border-radius: 8px;
      font-weight: 600;
      transition: 0.25s;
      margin-left: 16px;
      white-space: nowrap;
    }

    .btn-nav:hover {
      background: #D14D00;
      transform: scale(1.03);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }

    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--color-highlight);
      border-radius: 4px;
      transition: 0.3s;
    }

    /* 移动端导航 */
    .mobile-overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--color-primary);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      transform: translateX(100%);
      transition: transform 0.4s ease;
      z-index: 1000;
    }

    .mobile-overlay.open {
      transform: translateX(0);
    }

    .mobile-overlay a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
      border-bottom: 2px solid transparent;
    }

    .mobile-overlay a:hover {
      border-color: var(--color-accent);
    }

    .close-btn {
      position: absolute;
      top: 24px;
      right: 24px;
      background: transparent;
      border: none;
      font-size: 2.5rem;
      color: white;
      cursor: pointer;
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
      color: white;
    }

    #hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(15,43,29,0.85) 30%, rgba(15,43,29,0.2) 100%);
      z-index: 1;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      padding: 0 24px;
    }

    .hero-content h1 {
      font-size: 3.5rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }

    .hero-content h1 span {
      color: var(--color-accent);
    }

    .hero-sub {
      font-size: 1.4rem;
      margin-bottom: 1rem;
      color: rgba(255,255,255,0.9);
    }

    .hero-desc {
      font-size: 1.2rem;
      margin-bottom: 2.5rem;
      color: rgba(255,255,255,0.8);
      max-width: 600px;
    }

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

    .btn-primary {
      background: var(--color-highlight);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 600;
      font-size: 1rem;
      transition: 0.25s;
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }

    .btn-primary:hover {
      background: #D14D00;
      transform: scale(1.03);
    }

    .btn-outline {
      background: transparent;
      color: white;
      border: 2px solid white;
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 600;
      transition: 0.25s;
    }

    .btn-outline:hover {
      background: white;
      color: var(--color-primary);
    }

    /* 通用版块 */
    section {
      padding: 5rem 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 3rem;
    }

    .section-title h2 {
      color: var(--color-primary);
      position: relative;
      display: inline-block;
      padding-bottom: 0.5rem;
    }

    .section-title h2::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 60px;
      height: 4px;
      background: var(--color-accent);
      border-radius: 4px;
    }

    /* 核心优势 不对称网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }

    .feature-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
      border-left: 6px solid var(--color-accent);
    }

    .feature-card:nth-child(2) {
      border-left-color: var(--color-primary);
    }

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

    .feature-icon {
      font-size: 2.5rem;
      margin-bottom: 1rem;
      color: var(--color-primary);
    }

    /* 服务项目 图文交错 */
    .service-row {
      display: flex;
      align-items: center;
      gap: 2rem;
      margin-bottom: 4rem;
      flex-wrap: wrap;
    }

    .service-img {
      flex: 1 1 45%;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }

    .service-img img {
      width: 100%;
      height: 280px;
      object-fit: cover;
    }

    .service-text {
      flex: 1 1 45%;
    }

    /* 案例卡片横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 1.5rem;
      overflow-x: auto;
      padding-bottom: 1rem;
      scroll-snap-type: x mandatory;
    }

    .case-card {
      min-width: 280px;
      background: white;
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      scroll-snap-align: start;
      border-top: 4px solid var(--color-highlight);
    }

    .case-number {
      font-family: var(--font-number);
      font-size: 3rem;
      font-weight: 700;
      color: var(--color-highlight);
      letter-spacing: 2px;
    }

    /* 流程步骤 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      flex-wrap: wrap;
      gap: 1.5rem;
    }

    .step {
      flex: 1 1 180px;
      text-align: center;
      position: relative;
    }

    .step-icon {
      background: var(--color-primary);
      color: white;
      width: 60px;
      height: 60px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 1rem;
      font-size: 1.8rem;
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 1rem;
      border: 1px solid var(--color-border);
      overflow: hidden;
      
    }

    .faq-question {
      padding: 1.2rem 2rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: #F9F9F9;
      border-left: 4px solid var(--color-accent);
      transition: 0.35s;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease-in-out;
      background: white;
      padding: 0 2rem;
      color: var(--color-text-secondary);
    }

    .faq-item.active .faq-question {
      border-left-color: var(--color-highlight);
      background: white;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 1rem 2rem;
    }

    /* CTA 深色块 */
    #cta {
      background: #1A1A1A;
      color: white;
      text-align: center;
    }

    /* 页脚 */
    footer {
      background: #1A1A1A;
      color: #ccc;
      padding: 3rem 0 1.5rem;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
    }

    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .hero-content h1 { font-size: 2.2rem; }
      .features-grid { grid-template-columns: 1fr; }
      .service-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      .btn-group { flex-direction: column; align-items: flex-start; }
      h2 { font-size: 1.8rem; }
      section { padding: 3rem 0; }
    }