/* roulang page: index */
:root {
      --primary: #8B1E3F;
      --primary-glow: rgba(139, 30, 63, 0.4);
      --accent: #D4AF37;
      --accent-hover: #cba32b;
      --dark-bg: #1A1A1A;
      --darker-bg: #111111;
      --card-bg: #FFFFFF;
      --card-dark-bg: rgba(255,255,255,0.05);
      --text-light: #F5F5F5;
      --text-dark: #222222;
      --text-muted: #AAAAAA;
      --border-radius: 12px;
      --card-shadow: 0 4px 12px rgba(0,0,0,0.08);
      --card-hover-shadow: 0 12px 24px rgba(0,0,0,0.15);
      --transition: 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', sans-serif;
      background-color: var(--dark-bg);
      color: var(--text-light);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      outline: none;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      padding: 16px 0;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background: transparent;
    }
    .nav.scrolled {
      background: rgba(26, 26, 26, 0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.3);
    }
    .nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--text-light);
      letter-spacing: 2px;
    }
    .logo-icon {
      width: 24px;
      height: 24px;
      background: var(--accent);
      transform: rotate(45deg);
      border-radius: 4px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      color: var(--text-light);
      font-weight: 400;
      font-size: 1rem;
      opacity: 0.85;
      transition: opacity 0.2s, color 0.2s;
    }
    .nav-links a:hover {
      opacity: 1;
      color: var(--accent);
    }
    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 24px;
      border-radius: 8px;
      font-weight: 700;
      transition: background 0.2s, box-shadow 0.2s;
    }
    .nav-cta:hover {
      background: #a12349;
      box-shadow: 0 0 16px var(--primary-glow);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text-light);
      transition: 0.3s;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(17, 17, 17, 0.98);
        backdrop-filter: blur(16px);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 32px;
        transform: translateY(-100%);
        transition: transform 0.4s ease;
        z-index: 99;
      }
      .mobile-menu.active {
        transform: translateY(0);
      }
      .mobile-menu a {
        font-size: 1.8rem;
        color: var(--text-light);
      }
      .mobile-menu .nav-cta {
        font-size: 1.4rem;
        padding: 16px 36px;
      }
    }
    /* Hero */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 40%, #2a1a20 0%, #0f0f0f 90%);
      position: relative;
      overflow: hidden;
      padding-top: 80px;
    }
    .hero::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.25;
      mix-blend-mode: overlay;
    }
    .hero .container {
      position: relative;
      z-index: 2;
      display: flex;
      flex-direction: column;
      align-items: flex-start;
      max-width: 800px;
    }
    .hero h1 {
      font-size: 3.5rem;
      font-weight: 700;
      color: white;
      line-height: 1.3;
      margin-bottom: 24px;
      text-shadow: 0 0 20px rgba(212, 175, 55, 0.4);
      background: linear-gradient(135deg, #fff, #D4AF37);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .hero p {
      font-size: 1.25rem;
      color: #ddd;
      max-width: 600px;
      margin-bottom: 40px;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 16px 40px;
      border-radius: 8px;
      font-weight: 700;
      font-size: 1.1rem;
      letter-spacing: 1px;
      box-shadow: 0 0 20px var(--primary-glow);
      transition: 0.3s;
      animation: pulse 2.5s infinite;
    }
    .btn-primary:hover {
      background: #b1274a;
      box-shadow: 0 0 30px rgba(139,30,63,0.7);
      transform: translateY(-2px);
    }
    @keyframes pulse {
      0% { box-shadow: 0 0 0 0 rgba(139,30,63,0.6); }
      70% { box-shadow: 0 0 30px 15px rgba(139,30,63,0); }
      100% { box-shadow: 0 0 0 0 rgba(139,30,63,0); }
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent);
      color: var(--accent);
      padding: 14px 32px;
      border-radius: 8px;
      font-weight: 700;
      margin-left: 16px;
      transition: 0.3s;
    }
    .btn-outline:hover {
      background: var(--accent);
      color: #111;
    }
    @media (max-width: 768px) {
      .hero h1 {
        font-size: 2.5rem;
      }
      .hero p {
        font-size: 1rem;
      }
      .btn-primary {
        width: 100%;
        text-align: center;
      }
      .btn-outline {
        margin-left: 0;
        margin-top: 16px;
        width: 100%;
        text-align: center;
      }
    }
    /* 通用section */
    section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 48px 0;
      }
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      color: white;
      margin-bottom: 16px;
      position: relative;
    }
    .section-sub {
      color: var(--text-muted);
      max-width: 700px;
      margin-bottom: 48px;
    }
    /* Features 非对称 */
    .features-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr;
      gap: 24px;
    }
    .feature-card {
      background: var(--card-dark-bg);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: var(--border-radius);
      padding: 32px;
      backdrop-filter: blur(4px);
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-hover-shadow);
      border-color: rgba(212,175,55,0.3);
    }
    .feature-icon {
      font-size: 2.5rem;
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 1.5rem;
      margin-bottom: 12px;
      color: white;
    }
    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--border-radius);
      overflow: hidden;
      color: var(--text-dark);
      box-shadow: var(--card-shadow);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-hover-shadow);
    }
    .service-img {
      height: 160px;
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .service-img::after {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 4px;
      background: var(--primary);
    }
    .service-content {
      padding: 20px;
    }
    .service-content h4 {
      font-size: 1.2rem;
      margin-bottom: 8px;
    }
    .service-tags {
      display: flex;
      gap: 8px;
      margin: 12px 0;
    }
    .tag {
      background: #f0f0f0;
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 0.8rem;
      color: #555;
    }
    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 520px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 场景 */
    .scenario-row {
      display: flex;
      gap: 48px;
      align-items: center;
      margin-bottom: 64px;
    }
    .scenario-text h3 {
      font-size: 1.8rem;
      color: white;
    }
    .scenario-img {
      width: 45%;
      height: 260px;
      background-size: cover;
      background-position: center;
      border-radius: var(--border-radius);
    }
    @media (max-width: 768px) {
      .scenario-row {
        flex-direction: column;
      }
      .scenario-img {
        width: 100%;
        height: 200px;
      }
    }
    /* 案例数据 */
    .cases-bg {
      background: #141414;
    }
    .stats {
      display: flex;
      gap: 32px;
      justify-content: center;
    }
    .stat-item h3 {
      font-size: 2.5rem;
      color: var(--accent);
    }
    /* FAQ */
    .faq-item {
      background: #2A2A2A;
      border-radius: 8px;
      margin-bottom: 12px;
    }
    .faq-question {
      padding: 18px 24px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      font-weight: 700;
    }
    .faq-answer {
      padding: 0 24px 18px;
      color: #ccc;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* CTA */
    .cta-band {
      background: var(--primary);
      text-align: center;
      padding: 64px 24px;
    }
    /* 页脚 */
    .footer {
      background: #111;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 32px;
    }
    .footer a {
      color: #aaa;
      display: block;
      margin-bottom: 8px;
    }
    .footer a:hover {
      color: var(--accent);
      text-decoration: underline;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }