/* roulang page: index */
:root {
      --primary-green: #0A8F3C;
      --accent-orange: #F04E23;
      --dark: #1C1C1C;
      --light-bg: #F7F5F0;
      --text-main: #2D2D2D;
      --text-secondary: #5C5C5C;
      --white: #FFFFFF;
      --radius-card: 12px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
      --transition: 0.3s ease;
      --font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-family);
      color: var(--text-main);
      background-color: var(--light-bg);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, input, textarea {
      font-family: inherit;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--primary-green);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--dark);
      font-weight: 700;
    }
    .nav-links {
      display: flex;
      gap: 2.2rem;
      font-weight: 500;
      color: var(--text-main);
      align-items: center;
    }
    .nav-links a {
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
      font-size: 1rem;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 3px;
      background: var(--primary-green);
      transition: width 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--primary-green);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 10px;
    }
    .hamburger span {
      display: block;
      width: 26px;
      height: 2.5px;
      background: var(--dark);
      border-radius: 2px;
      transition: 0.3s;
    }
    /* 移动全屏菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10,143,60,0.96);
      backdrop-filter: blur(10px);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: flex-start;
      padding-left: 48px;
      transform: translateX(100%);
      transition: transform 0.4s ease;
      z-index: 999;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 2.2rem;
      font-weight: 700;
      color: white;
      margin: 18px 0;
      letter-spacing: 2px;
    }
    .close-menu {
      position: absolute;
      top: 24px;
      right: 28px;
      background: none;
      border: none;
      font-size: 2.5rem;
      color: white;
      cursor: pointer;
    }
    /* Hero */
    .hero {
      height: 100vh;
      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;
      top: 0; left: 0;
      width: 100%; height: 100%;
      background: rgba(28,28,28,0.55);
      background: linear-gradient(135deg, rgba(28,28,28,0.75) 0%, rgba(10,143,60,0.35) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }
    .hero h1 {
      font-size: 3.4rem;
      font-weight: 900;
      line-height: 1.2;
      margin-bottom: 1.4rem;
    }
    .hero h1 span {
      color: var(--accent-orange);
    }
    .hero p {
      font-size: 1.25rem;
      color: #e0e0e0;
      margin-bottom: 2.5rem;
      max-width: 600px;
    }
    .btn-group {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 600;
      font-size: 1rem;
      transition: var(--transition);
      text-align: center;
      cursor: pointer;
    }
    .btn-primary {
      background: var(--primary-green);
      color: white;
      border: 2px solid var(--primary-green);
    }
    .btn-primary:hover {
      background: #077A32;
      border-color: #077A32;
    }
    .btn-outline {
      border: 2px solid var(--accent-orange);
      color: white;
      background: transparent;
    }
    .btn-outline:hover {
      background: var(--accent-orange);
      border-color: var(--accent-orange);
      color: white;
    }
    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      font-size: 2rem;
      color: white;
      animation: bounce 2s infinite;
    }
    @keyframes bounce {
      0%,20%,50%,80%,100%{transform:translateX(-50%) translateY(0);}
      40%{transform:translateX(-50%) translateY(-10px);}
      60%{transform:translateX(-50%) translateY(-5px);}
    }
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--dark);
    }
    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }
    /* 优势卡片 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
      margin-top: 20px;
    }
    .adv-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px 20px;
      box-shadow: var(--shadow-card);
      text-align: center;
      transition: var(--transition);
    }
    .adv-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .adv-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--accent-orange);
      line-height: 1.2;
    }
    .adv-underline {
      width: 40px;
      height: 3px;
      background: var(--primary-green);
      margin: 12px auto;
    }
    .adv-text {
      color: var(--text-secondary);
      font-weight: 500;
    }
    /* 服务卡片错落 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
      align-items: start;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-card);
      display: flex;
      gap: 20px;
      transition: var(--transition);
      border-left: 4px solid transparent;
    }
    .service-card:hover {
      border-left-color: var(--primary-green);
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .service-card.middle {
      margin-top: -20px;
      margin-bottom: 20px;
    }
    .service-icon {
      width: 64px;
      height: 64px;
      background: var(--primary-green);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 2rem;
      flex-shrink: 0;
    }
    /* 案例网格 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
      transition: transform 0.4s ease;
    }
    .case-card:hover .case-img {
      transform: scale(1.05);
    }
    .case-info {
      padding: 20px;
    }
    .case-tag {
      display: inline-block;
      border: 1px solid var(--primary-green);
      color: var(--primary-green);
      border-radius: 20px;
      padding: 4px 14px;
      font-size: 0.8rem;
      margin-top: 10px;
    }
    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      padding: 18px 22px;
      cursor: pointer;
      border-left: 4px solid transparent;
      transition: background 0.25s;
    }
    .faq-item.active {
      background: #F0FAF4;
      border-left-color: var(--primary-green);
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 1.1rem;
    }
    .faq-icon {
      color: var(--accent-orange);
      font-weight: bold;
      font-size: 1.5rem;
      line-height: 1;
    }
    .faq-answer {
      margin-top: 12px;
      color: var(--text-secondary);
      display: none;
      line-height: 1.6;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* CTA */
    .cta-section {
      background: var(--dark);
      color: white;
      padding: 90px 0;
    }
    .cta-form {
      display: flex;
      gap: 16px;
      margin-top: 32px;
      flex-wrap: wrap;
    }
    .cta-form input {
      flex: 1;
      padding: 14px 18px;
      border-radius: 8px;
      border: none;
      background: white;
      font-size: 1rem;
    }
    .btn-submit {
      background: var(--accent-orange);
      color: white;
      border: none;
      padding: 14px 36px;
      border-radius: 8px;
      font-weight: 700;
      cursor: pointer;
      transition: 0.2s;
    }
    .btn-submit:hover {
      background: #d63e1a;
    }
    /* 页脚 */
    .footer {
      background: #F7F5F0;
      padding: 60px 0 30px;
      color: var(--text-main);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: var(--text-secondary);
      margin-bottom: 8px;
      display: block;
    }
    .footer a:hover {
      color: var(--primary-green);
    }
    .copyright {
      border-top: 1px solid #ddd;
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      color: var(--text-secondary);
      font-size: 0.9rem;
    }
    @media (max-width: 1024px) {
      .advantages-grid { grid-template-columns: repeat(2,1fr); }
      .services-grid { grid-template-columns: 1fr; }
      .service-card.middle { margin-top:0; }
      .cases-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 2.2rem; }
      .advantages-grid { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .cta-form { flex-direction: column; }
      .btn-submit { width: 100%; }
    }