/* roulang page: index */
:root {
      --primary: #C41E5A;
      --primary-gradient: linear-gradient(135deg, #C41E5A 0%, #E12A3C 100%);
      --accent: #00E5FF;
      --bg-deep: #0B0C10;
      --bg-section: #13151A;
      --text-white: #F2F2F2;
      --text-muted: #A0A3B1;
      --card-bg: rgba(19, 21, 26, 0.8);
      --card-border: rgba(0, 229, 255, 0.15);
      --card-hover-border: rgba(0, 229, 255, 0.5);
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-glow: 0 0 20px rgba(0, 229, 255, 0.2);
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --nav-height: 70px;
      --container-max: 1280px;
      --transition: all 0.25s ease;
    }

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

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-deep);
      color: var(--text-white);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(11, 12, 16, 0.92);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      display: flex;
      align-items: center;
      z-index: 1000;
      border-bottom: 1px solid rgba(0, 229, 255, 0.1);
      transition: var(--transition);
    }

    .header-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      text-decoration: none;
      color: var(--text-white);
      font-weight: 800;
      font-size: 1.8rem;
      letter-spacing: 1px;
      gap: 8px;
    }

    .logo span {
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .nav-links {
      display: flex;
      gap: 2.2rem;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      color: var(--text-muted);
      text-decoration: none;
      font-weight: 500;
      font-size: 0.95rem;
      transition: var(--transition);
      position: relative;
      padding: 6px 0;
    }

    .nav-links a:hover,
    .nav-links a:focus-visible {
      color: var(--accent);
      outline: none;
      text-shadow: 0 0 8px rgba(0, 229, 255, 0.5);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s ease;
      box-shadow: 0 0 8px var(--accent);
    }

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

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 8px;
    }

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

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-repeat: no-repeat;
      margin-top: 0;
      padding-top: var(--nav-height);
    }

    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(11,12,16,0.85) 0%, rgba(11,12,16,0.4) 60%);
      z-index: 1;
    }

    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      padding: 20px 0;
    }

    .hero h1 {
      font-size: clamp(2.8rem, 6vw, 4.2rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      background: linear-gradient(to right, #fff, #ddd);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-sub {
      font-size: 1.3rem;
      color: var(--text-muted);
      margin-bottom: 2.5rem;
      max-width: 550px;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary-gradient);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 1rem;
      cursor: pointer;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: var(--transition);
      box-shadow: 0 8px 18px rgba(196, 30, 90, 0.35);
      letter-spacing: 0.5px;
    }

    .btn-primary:hover {
      filter: brightness(1.2);
      box-shadow: 0 12px 24px rgba(226, 42, 60, 0.5);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent);
      color: var(--accent);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      text-decoration: none;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: rgba(0, 229, 255, 0.08);
      box-shadow: 0 0 14px rgba(0, 229, 255, 0.4);
    }

    /* 通用板块 */
    section {
      padding: 90px 0;
    }

    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 14px;
      color: var(--text-white);
    }

    .section-sub {
      text-align: center;
      color: var(--text-muted);
      max-width: 650px;
      margin: 0 auto 54px;
      font-size: 1.1rem;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }

    .card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 28px 22px;
      transition: var(--transition);
      backdrop-filter: blur(10px);
    }

    .card:hover {
      border-color: var(--card-hover-border);
      box-shadow: var(--shadow-glow);
      transform: translateY(-5px);
    }

    .icon-circle {
      width: 56px;
      height: 56px;
      background: rgba(0, 229, 255, 0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      font-size: 2rem;
    }

    .card h3 {
      font-size: 1.5rem;
      margin-bottom: 12px;
    }

    /* 服务卡片图片 */
    .service-img {
      width: 100%;
      height: 180px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 20px;
    }

    .text-accent {
      color: var(--accent);
    }

    .data-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.2;
    }

    /* 流程 */
    .steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      flex-wrap: wrap;
    }

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

    .step-circle {
      width: 60px;
      height: 60px;
      background: var(--primary-gradient);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.6rem;
      margin: 0 auto 16px;
    }

    /* FAQ */
    .faq-item {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      margin-bottom: 16px;
      transition: var(--transition);
    }

    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      color: var(--text-white);
      padding: 20px 24px;
      font-weight: 700;
      font-size: 1.1rem;
      text-align: left;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }

    .faq-answer {
      padding: 0 24px 20px;
      color: var(--text-muted);
      display: none;
    }

    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active {
      border-color: var(--accent);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(145deg, #1a1c24 0%, #0f1117 100%);
      text-align: center;
    }

    /* Footer */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .copyright {
      border-top: 1px solid rgba(255,255,255,0.08);
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      color: var(--text-muted);
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2,1fr); }
      .grid-4 { grid-template-columns: repeat(2,1fr); }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-3, .grid-4, .footer-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 2.4rem; }
      .steps { flex-direction: column; gap: 32px; }
    }