/* roulang page: index */
:root {
      --primary: #C41E3A;
      --primary-hover: #A01830;
      --secondary: #1E1E1E;
      --accent-gold: #C9A96E;
      --bg-warm: #FAF8F5;
      --bg-dark: #0F0F0F;
      --text-dark: #1E1E1E;
      --text-body: #3A3A3A;
      --text-muted: #6B6B6B;
      --text-light: #EAE5DE;
      --border-light: #E5E0D8;
      --border-input: #C8C3B8;
      --green-accent: #2D6A4F;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 6px 16px rgba(0,0,0,0.06);
      --shadow-hover: 0 4px 8px rgba(0,0,0,0.06), 0 12px 24px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-sans: 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', sans-serif;
      --max-width: 1280px;
      --nav-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding-left: 40px;
      padding-right: 40px;
    }
    h1, h2, h3, h4 {
      color: var(--text-dark);
      font-weight: 600;
    }
    h1 {
      font-size: 36px;
      line-height: 1.2;
      letter-spacing: -0.5px;
      font-weight: 700;
    }
    h2 {
      font-size: 28px;
      line-height: 1.35;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 20px;
      line-height: 1.4;
    }
    p {
      max-width: 680px;
      color: var(--text-body);
    }
    .text-muted {
      color: var(--text-muted);
    }
    .section {
      padding: 100px 0;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(250,248,245,0.92);
      backdrop-filter: blur(12px);
      z-index: 100;
      display: flex;
      align-items: center;
      transition: background 0.3s, box-shadow 0.3s;
    }
    .header.scrolled {
      background: var(--bg-warm);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
    }
    .logo {
      font-weight: 700;
      font-size: 22px;
      color: var(--secondary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.3px;
    }
    .logo span {
      color: var(--primary);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-dark);
      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::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--secondary);
      transition: 0.25s;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--bg-warm);
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 32px;
      z-index: 99;
    }
    .mobile-menu a {
      font-size: 22px;
      font-weight: 600;
      color: var(--secondary);
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #0F0F0F 0%, #1A1A1A 100%);
      color: white;
      min-height: 90vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      margin-top: 0;
      padding-top: var(--nav-height);
    }
    .hero-bg {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.18;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      padding: 60px 0;
    }
    .hero h1 {
      color: white;
      font-size: 48px;
      margin-bottom: 20px;
      line-height: 1.2;
    }
    .hero .sub {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 36px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: scale(1.02);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.7);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      transition: all 0.2s;
    }
    .btn-outline:hover {
      border-color: var(--primary);
      color: var(--primary);
    }
    /* 核心优势 非对称 */
    .features-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      margin-top: 48px;
    }
    .feature-item {
      display: flex;
      gap: 24px;
      align-items: flex-start;
    }
    .feature-icon {
      width: 52px;
      height: 52px;
      background: rgba(196,30,58,0.08);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 24px;
    }
    .feature-text h3 {
      margin-bottom: 8px;
    }
    /* 服务体系 横向滚动 */
    .services-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 24px;
      scroll-snap-type: x mandatory;
      margin-top: 40px;
    }
    .service-card {
      min-width: 300px;
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      scroll-snap-align: start;
      display: flex;
      flex-direction: column;
      transition: all 0.3s;
      border-left: 4px solid var(--primary);
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .service-img {
      height: 160px;
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-card) var(--radius-card) 0 0;
    }
    .service-body {
      padding: 24px;
    }
    /* 数据 */
    .stats-row {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 32px;
      margin-top: 48px;
    }
    .stat-item {
      text-align: left;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
    }
    /* FAQ */
    .faq-list {
      margin-top: 36px;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      padding: 0 24px;
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      font-weight: 600;
      font-size: 16px;
      padding: 20px 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text-dark);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      color: #555;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }
    .faq-icon {
      transition: transform 0.25s;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }
    /* 联系表单 */
    .contact-form {
      display: flex;
      flex-direction: column;
      gap: 24px;
      max-width: 520px;
      margin-top: 36px;
    }
    .input-group {
      position: relative;
    }
    .input-group input, .input-group textarea {
      width: 100%;
      border: none;
      border-bottom: 1px solid var(--border-input);
      padding: 12px 0;
      background: transparent;
      outline: none;
      font-size: 16px;
      transition: border 0.2s;
    }
    .input-group input:focus, .input-group textarea:focus {
      border-bottom: 2px solid var(--primary);
    }
    .footer {
      background: var(--secondary);
      color: var(--text-light);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: var(--text-light);
      opacity: 0.8;
    }
    .footer a:hover {
      color: var(--accent-gold);
      opacity: 1;
    }
    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .features-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 36px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 28px; }
      .section { padding: 70px 0; }
      .stats-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      .btn-group { flex-direction: column; align-items: flex-start; }
    }