/* roulang page: index */
:root {
      --primary: #7B2FF7;
      --accent: #00F0FF;
      --bg-dark: #0D0D0D;
      --bg-card: #1A1A1A;
      --text-white: #FFFFFF;
      --text-gray: #B3B3B3;
      --border-light: rgba(123, 47, 247, 0.15);
      --radius-lg: 16px;
      --radius-pill: 50px;
      --shadow-glow: 0 0 30px rgba(0, 240, 255, 0.15);
      --transition: 0.3s ease;
      --font-cn: "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-en: "Inter", "SF Pro Display", sans-serif;
      --max-width: 1280px;
      --header-height: 80px;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--header-height);
    }

    body {
      font-family: var(--font-cn);
      background-color: var(--bg-dark);
      color: var(--text-gray);
      line-height: 1.8;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, .font-en {
      font-family: var(--font-en);
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-cn);
      border: none;
      background: none;
      outline: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: var(--transition);
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 2rem;
    }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 2rem;
      z-index: 1000;
      background: transparent;
      transition: background 0.4s ease, backdrop-filter 0.4s ease;
    }

    .header.scrolled {
      background: rgba(13, 13, 13, 0.9);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      box-shadow: 0 1px 0 rgba(255,255,255,0.05);
    }

    .brand {
      font-size: 1.8rem;
      font-weight: 700;
      background: linear-gradient(135deg, #7B2FF7, #00F0FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 0.02em;
      font-family: var(--font-cn);
    }

    .nav-links {
      display: flex;
      gap: 2.5rem;
      align-items: center;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-gray);
      position: relative;
      padding: 0.25rem 0;
      transition: color 0.2s;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent);
      transition: width 0.3s ease;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent);
    }

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

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
      z-index: 1001;
    }

    .hamburger span {
      display: block;
      width: 26px;
      height: 2px;
      background: var(--text-white);
      transition: 0.3s;
      border-radius: 2px;
    }

    /* 移动端菜单面板 */
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 280px;
      height: 100vh;
      background: var(--bg-dark);
      backdrop-filter: blur(24px);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 2rem;
      transition: right 0.4s ease;
      z-index: 999;
      padding: 2rem;
    }

    .mobile-menu.open {
      right: 0;
    }

    .mobile-menu a {
      font-size: 1.5rem;
      color: var(--text-white);
      font-weight: 600;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(123,47,247,0.7) 0%, rgba(0,240,255,0.4) 100%);
      mix-blend-mode: multiply;
      z-index: 1;
    }

    .hero::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(13,13,13,0.65);
      z-index: 2;
    }

    .hero-content {
      position: relative;
      z-index: 3;
      max-width: 800px;
    }

    .hero h1 {
      font-size: clamp(3rem, 8vw, 5rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      color: var(--text-white);
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }

    .hero h1 span {
      background: linear-gradient(to right, #7B2FF7, #00F0FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero p {
      font-size: 1.2rem;
      color: #d1d1d1;
      max-width: 600px;
      margin-bottom: 2.5rem;
    }

    .btn-primary {
      background: var(--primary);
      color: var(--accent);
      font-weight: 600;
      padding: 0.9rem 2.5rem;
      border-radius: var(--radius-pill);
      font-size: 1rem;
      letter-spacing: 0.5px;
      transition: all 0.3s ease;
      box-shadow: 0 4px 20px rgba(123,47,247,0.4);
    }

    .btn-primary:hover {
      background: var(--accent);
      color: #0D0D0D;
      box-shadow: 0 0 28px rgba(0,240,255,0.5);
      transform: scale(1.05);
    }

    /* 区块通用 */
    section {
      padding: 120px 0;
    }

    .section-title {
      font-size: clamp(2rem, 5vw, 3rem);
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 1rem;
      text-align: center;
    }

    .section-sub {
      color: var(--text-gray);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 3rem;
    }

    /* 核心优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 2rem;
    }

    .adv-card {
      background: var(--bg-card);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
      padding: 2rem;
      transition: var(--transition);
      text-align: center;
    }

    .adv-card:hover {
      border-color: var(--accent);
      box-shadow: var(--shadow-glow);
      transform: translateY(-6px);
    }

    .adv-icon {
      width: 48px;
      height: 48px;
      margin: 0 auto 1rem;
      color: var(--accent);
    }

    .adv-card h3 {
      font-size: 1.4rem;
      color: var(--text-white);
      margin-bottom: 0.8rem;
    }

    /* 服务体系 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--bg-card);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
      display: flex;
      overflow: hidden;
      transition: var(--transition);
    }

    .service-card:hover {
      border-color: var(--accent);
      box-shadow: var(--shadow-glow);
      transform: translateY(-6px);
    }

    .service-text {
      flex: 1;
      padding: 2rem;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .service-text h3 {
      color: var(--text-white);
      margin-bottom: 0.8rem;
      font-size: 1.5rem;
    }

    .service-img {
      width: 45%;
      position: relative;
      overflow: hidden;
    }

    .service-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      filter: brightness(0.7) contrast(1.1);
      transition: 0.4s;
    }

    .service-img::after {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(123,47,247,0.35);
      mix-blend-mode: multiply;
    }

    .link-arrow {
      color: var(--accent);
      font-weight: 600;
      margin-top: 1rem;
      display: inline-flex;
      align-items: center;
      gap: 0.3rem;
      transition: gap 0.2s;
    }

    .link-arrow:hover {
      gap: 0.6rem;
    }

    /* 流程 */
    .steps {
      display: flex;
      justify-content: space-between;
      position: relative;
    }

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

    .step-num {
      font-size: 4rem;
      font-weight: 800;
      color: rgba(0,240,255,0.2);
      line-height: 1;
      margin-bottom: 0.5rem;
    }

    .step-item h4 {
      color: white;
      font-size: 1.3rem;
      margin: 0.5rem 0;
    }

    /* 数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      background: url('/assets/images/backpic/back-2.webp') center/cover;
      position: relative;
      border-radius: var(--radius-lg);
      overflow: hidden;
      padding: 3rem 2rem;
    }

    .stats-grid::before {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(13,13,13,0.8);
    }

    .stat-item {
      position: relative;
      z-index: 2;
      text-align: center;
    }

    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      background: linear-gradient(135deg, #7B2FF7, #00F0FF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

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

    .faq-question {
      width: 100%;
      background: none;
      padding: 1.2rem 1.8rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 700;
      color: var(--text-white);
      font-size: 1.1rem;
      text-align: left;
    }

    .faq-icon {
      font-size: 1.5rem;
      transition: transform 0.3s;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #111;
    }

    .faq-answer p {
      padding: 1.5rem;
      color: var(--text-gray);
    }

    .faq-item.open .faq-answer {
      max-height: 200px;
    }

    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #7B2FF7, #00F0FF);
      text-align: center;
      padding: 4rem 2rem;
      border-radius: 24px;
      margin: 0 1rem;
    }

    .cta-banner h2 {
      color: #fff;
      font-size: 2.5rem;
      margin-bottom: 1.5rem;
    }

    .btn-white {
      background: white;
      color: #7B2FF7;
      padding: 0.9rem 2.8rem;
      border-radius: 50px;
      font-weight: 700;
    }

    .btn-white:hover {
      background: #0D0D0D;
      color: var(--accent);
    }

    /* 页脚 */
    .footer {
      background: var(--bg-dark);
      border-top: 1px solid rgba(255,255,255,0.05);
      padding: 2rem;
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      align-items: center;
      color: #B3B3B3;
    }

    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 1.5rem;
      }
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .advantages-grid,
      .stats-grid {
        grid-template-columns: 1fr;
      }
      .steps {
        flex-direction: column;
        gap: 2rem;
      }
      .service-card {
        flex-direction: column;
      }
      .service-img {
        width: 100%;
        height: 200px;
      }
      section {
        padding: 80px 0;
      }
    }