/* roulang page: index */
:root {
      --primary: #F04E23;
      --primary-dark: #D43C1A;
      --accent: #FFC107;
      --accent-dark: #E0A800;
      --black: #1A1A1A;
      --dark-gray: #2D2D2D;
      --light-gray: #F5F5F5;
      --white: #FFFFFF;
      --text-main: #1A1A1A;
      --text-secondary: #4A4A4A;
      --text-light: #8A8A8A;
      --border-light: #E0E0E0;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --shadow-card: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.12);
      --shadow-nav: 0 1px 8px rgba(0,0,0,0.08);
      --font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --max-width: 1200px;
      --space-section: 100px;
      --transition-smooth: all 0.3s ease;
    }

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

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

    body {
      font-family: var(--font-family);
      color: var(--text-main);
      background-color: var(--white);
      line-height: 1.8;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }

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

    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
      outline: none;
      border: none;
      background: transparent;
    }

    button {
      cursor: pointer;
      transition: var(--transition-smooth);
    }

    button:focus-visible, a:focus-visible, input:focus-visible, textarea:focus-visible {
      outline: 2px solid var(--primary);
      outline-offset: 2px;
      border-radius: 2px;
    }

    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
      width: 100%;
    }

    /* 导航 */
    .header {
      position: sticky;
      top: 0;
      background: var(--white);
      z-index: 1000;
      transition: box-shadow 0.3s ease;
      border-bottom: 1px solid transparent;
    }

    .header.scrolled {
      box-shadow: var(--shadow-nav);
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 70px;
    }

    .logo {
      display: flex;
      align-items: center;
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: -0.5px;
      color: var(--black);
    }

    .logo .num {
      color: var(--primary);
      font-style: italic;
      font-weight: 800;
      margin-right: 2px;
      transform: skewX(-8deg);
      display: inline-block;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }

    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-secondary);
      position: relative;
      padding: 4px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s ease;
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: var(--white);
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      font-weight: 600;
      font-size: 0.9rem;
      letter-spacing: 0.3px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition-smooth);
      box-shadow: 0 4px 10px rgba(240,78,35,0.25);
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(240,78,35,0.35);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition-smooth);
    }

    .btn-outline:hover {
      background: var(--primary);
      color: var(--white);
      transform: translateY(-2px);
    }

    .btn-cta {
      background: var(--accent);
      color: var(--black);
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-weight: 700;
      box-shadow: 0 4px 12px rgba(255,193,7,0.3);
      transition: var(--transition-smooth);
    }

    .btn-cta:hover {
      background: var(--accent-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(255,193,7,0.45);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 4px;
      background: transparent;
      border: none;
      cursor: pointer;
    }

    .hamburger span {
      width: 24px;
      height: 2.5px;
      background: var(--black);
      border-radius: 2px;
      transition: var(--transition-smooth);
    }

    .mobile-menu {
      display: none;
    }

    /* Hero */
    .hero {
      background: var(--black);
      color: var(--white);
      position: relative;
      overflow: hidden;
      min-height: 85vh;
      display: flex;
      align-items: center;
    }

    .hero-bg {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.45;
      z-index: 0;
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(26,26,26,0.85) 0%, rgba(26,26,26,0.4) 70%);
      z-index: 1;
    }

    .hero .container {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: flex-start;
      padding-top: 80px;
      padding-bottom: 80px;
    }

    .hero-content {
      max-width: 650px;
    }

    .hero h1 {
      font-size: 2.8rem;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }

    .hero .subtitle {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 36px;
      line-height: 1.6;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      z-index: 2;
      animation: bounce 2s infinite;
      color: rgba(255,255,255,0.7);
      font-size: 1.8rem;
    }

    @keyframes bounce {
      0%, 20%, 50%, 80%, 100% { transform: translateX(-50%) translateY(0); }
      40% { transform: translateX(-50%) translateY(-10px); }
      60% { transform: translateX(-50%) translateY(-5px); }
    }

    /* 通用区块 */
    .section {
      padding-top: var(--space-section);
      padding-bottom: var(--space-section);
    }

    .section-dark {
      background: var(--black);
      color: var(--white);
    }

    .section-light {
      background: var(--light-gray);
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }

    .section-subtitle {
      text-align: center;
      color: var(--text-secondary);
      max-width: 600px;
      margin-left: auto;
      margin-right: auto;
      margin-bottom: 50px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }

    .service-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
      border: 1px solid transparent;
      display: flex;
      flex-direction: column;
    }

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

    .service-card img {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 20px;
    }

    .service-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 8px;
    }

    .service-card p {
      color: var(--text-secondary);
      flex: 1;
      margin-bottom: 16px;
    }

    .text-link {
      color: var(--primary);
      font-weight: 600;
      font-size: 0.9rem;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    .text-link:hover {
      text-decoration: underline;
    }

    .stats-row {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 30px;
    }

    .stat-item {
      text-align: center;
    }

    .stat-number {
      font-size: 3.5rem;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.1;
    }

    .stat-label {
      font-size: 0.9rem;
      font-weight: 500;
      letter-spacing: 0.5px;
      color: var(--text-light);
    }

    .case-card {
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }

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

    .case-card img {
      width: 100%;
      height: 240px;
      object-fit: cover;
    }

    .case-info {
      padding: 20px;
      background: var(--white);
    }

    .process-steps {
      display: flex;
      justify-content: space-between;
      gap: 20px;
      flex-wrap: wrap;
    }

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

    .step-number {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 8px;
    }

    .faq-item {
      background: var(--white);
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      overflow: hidden;
      border: 1px solid var(--border-light);
    }

    .faq-question {
      background: var(--light-gray);
      padding: 16px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      user-select: none;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s ease;
      background: var(--white);
      border-left: 3px solid var(--primary);
      padding: 0 24px;
    }

    .faq-item.active .faq-answer {
      max-height: 220px;
      padding: 20px 24px;
    }

    .faq-item.active {
      border-color: var(--primary);
    }

    .contact-form {
      display: grid;
      grid-template-columns: 1fr 1fr 1fr;
      gap: 16px;
      align-items: end;
    }

    .contact-form input,
    .contact-form textarea {
      background: var(--light-gray);
      border-radius: var(--radius-input);
      padding: 12px 16px;
      width: 100%;
      border: 1px solid transparent;
      transition: var(--transition-smooth);
    }

    .contact-form input:focus,
    .contact-form textarea:focus {
      border-color: var(--primary);
      background: var(--white);
    }

    .footer {
      background: var(--dark-gray);
      color: rgba(255,255,255,0.8);
      padding: 60px 0 20px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 40px;
    }

    .footer a {
      color: rgba(255,255,255,0.7);
    }

    .footer a:hover {
      color: var(--primary);
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.15);
      padding-top: 20px;
      text-align: center;
      font-size: 0.85rem;
    }

    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .mobile-menu {
        display: none;
        flex-direction: column;
        background: var(--white);
        padding: 20px;
        gap: 16px;
        border-top: 1px solid var(--border-light);
      }
      .mobile-menu.active { display: flex; }
      .hero h1 { font-size: 2rem; }
      .grid-3 { grid-template-columns: 1fr; }
      .contact-form { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 480px) {
      .grid-4 { grid-template-columns: 1fr; }
      .stats-row { flex-direction: column; align-items: center; }
      .process-steps { flex-direction: column; }
    }