/* roulang page: index */
:root {
      --primary: #7C3AED;
      --primary-hover: #6D28D9;
      --accent: #FF6B6B;
      --dark-bg: #1E1E2E;
      --light-bg: #FAFAFA;
      --text-main: #2D2D3A;
      --text-muted: #6B7280;
      --white: #FFFFFF;
      --border: #E5E7EB;
      --success: #10B981;
      --radius-sm: 12px;
      --radius-md: 16px;
      --radius-lg: 20px;
      --radius-full: 50px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --shadow-btn: 0 4px 14px rgba(124,58,237,0.3);
      --transition: 0.3s ease;
      --max-width: 1200px;
      --header-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      background-color: var(--light-bg);
      color: var(--text-main);
      line-height: 1.6;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      z-index: 1000;
      transition: box-shadow 0.3s;
      display: flex;
      align-items: center;
    }
    .header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.06);
    }
    .header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
    }
    .logo-icon {
      font-size: 1.8rem;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2rem;
    }
    .nav-link {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-main);
      transition: color 0.2s;
      position: relative;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s;
    }
    .nav-link:hover,
    .nav-link.active {
      color: var(--primary);
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      font-weight: 600;
      font-size: 0.95rem;
      border-radius: var(--radius-full);
      transition: background 0.25s, transform 0.2s, box-shadow 0.25s;
      border: none;
      cursor: pointer;
      gap: 6px;
    }
    .btn-primary {
      background: var(--primary);
      color: var(--white);
      box-shadow: var(--shadow-btn);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: scale(1.03);
      box-shadow: 0 8px 22px rgba(124,58,237,0.45);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary);
      color: var(--white);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--text-main);
      border-radius: 2px;
      transition: 0.3s;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(30,30,46,0.95);
      backdrop-filter: blur(12px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2.5rem;
      z-index: 999;
      animation: fadeIn 0.3s;
    }
    .mobile-menu a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
    }
    .mobile-menu .close-menu {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 2rem;
      background: none;
      border: none;
      color: white;
    }
    @keyframes fadeIn {
      from { opacity: 0; }
      to { opacity: 1; }
    }
    /* Hero */
    .hero {
      padding: 140px 0 80px;
      background: linear-gradient(135deg, var(--dark-bg) 0%, #2d2040 100%);
      position: relative;
      overflow: hidden;
      color: white;
    }
    .hero::before {
      content: '';
      position: absolute;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(124,58,237,0.4) 0%, transparent 70%);
      top: -100px;
      right: -80px;
      animation: floatParticle 8s infinite alternate;
    }
    @keyframes floatParticle {
      0% { transform: translate(0,0); }
      100% { transform: translate(-30px, 30px); }
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-content {
      flex: 1;
    }
    .hero h1 {
      font-size: 3.2rem;
      font-weight: 800;
      line-height: 1.15;
      letter-spacing: -0.02em;
      margin-bottom: 1.25rem;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 2rem;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 24px;
      min-height: 360px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
      position: relative;
    }
    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 1rem;
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 3rem;
    }
    /* 优势区非对称 */
    .features-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr;
      gap: 28px;
      margin-top: 2rem;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-md);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 2.2rem;
      margin-bottom: 1rem;
    }
    .feature-card h3 {
      font-size: 1.4rem;
      margin-bottom: 0.5rem;
    }
    .second-row {
      grid-template-columns: repeat(3,1fr);
    }
    /* 场景卡片横向 */
    .scenario-list {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .scenario-card {
      display: flex;
      background: var(--white);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border);
      overflow: hidden;
      transition: 0.25s;
    }
    .scenario-card:hover {
      border-color: var(--primary);
      background: #faf5ff;
    }
    .scenario-img {
      width: 180px;
      min-height: 140px;
      background-size: cover;
      background-position: center;
    }
    .scenario-text {
      padding: 1.5rem;
    }
    /* 案例跑马灯模拟 */ 
    .cases-stats {
      display: flex;
      justify-content: center;
      gap: 3rem;
      margin-bottom: 2.5rem;
      font-weight: 700;
      font-size: 2rem;
      color: var(--primary);
    }
    .reviews {
      display: flex;
      gap: 20px;
      overflow-x: auto;
      padding-bottom: 10px;
    }
    .review-card {
      min-width: 260px;
      background: white;
      border-radius: var(--radius-sm);
      padding: 1.5rem;
      box-shadow: var(--shadow-card);
    }
    /* 下载步骤 */
    .steps {
      background: #F5F3FF;
    }
    .step-item {
      display: flex;
      gap: 2rem;
      align-items: center;
      margin-bottom: 2rem;
    }
    .step-num {
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary);
      opacity: 0.25;
      width: 70px;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 1.2rem 0;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s;
      color: var(--text-muted);
    }
    .faq-answer.open {
      max-height: 200px;
      margin-top: 0.8rem;
    }
    /* CTA */
    .cta-band {
      background: linear-gradient(135deg, var(--primary), var(--accent));
      text-align: center;
      color: white;
      padding: 80px 0;
    }
    /* 页脚 */
    .footer {
      background: var(--dark-bg);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    @media (max-width: 1024px) {
      .hero h1 { font-size: 2.6rem; }
      .features-grid { grid-template-columns: 1fr; }
      .scenario-card { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .hero .container { flex-direction: column; }
      .hero-image { width: 100%; min-height: 250px; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }