/* roulang page: index */
:root {
      --primary-bg: #0A0E17;
      --secondary-bg: #1E293B;
      --purple: #A855F7;
      --cyan: #22D3EE;
      --white: #F8FAFC;
      --text-muted: #CBD5E1;
      --card-bg: rgba(30, 41, 59, 0.6);
      --glass-border: rgba(168, 85, 247, 0.25);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --shadow-purple: 0 10px 30px -10px rgba(168, 85, 247, 0.5);
      --shadow-cyan: 0 0 20px rgba(34, 211, 238, 0.4);
      --transition: all 0.3s ease;
    }

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

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
      background-color: var(--primary-bg);
      color: var(--white);
      line-height: 1.8;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(10, 14, 23, 0.85);
      backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--purple);
      z-index: 1000;
      transition: var(--transition);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 76px;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--white);
      text-decoration: none;
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo span {
      background: linear-gradient(135deg, var(--purple), var(--cyan));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
    }

    .nav-links a {
      color: var(--white);
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      transition: color 0.2s;
      position: relative;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--cyan);
      transition: width 0.3s;
    }

    .nav-links a:hover {
      color: var(--cyan);
    }

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

    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }

    .menu-toggle span {
      width: 28px;
      height: 3px;
      background: var(--white);
      border-radius: 4px;
      transition: var(--transition);
    }

    /* 首屏英雄 */
    .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;
      padding-top: 100px;
      isolation: isolate;
    }

    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 30% 30%, rgba(168,85,247,0.15), transparent 70%);
      z-index: 0;
    }

    .hero .container {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 48px;
      position: relative;
      z-index: 2;
    }

    .hero-text {
      flex: 1 1 500px;
    }

    .hero-text h1 {
      font-size: 56px;
      line-height: 1.2;
      font-weight: 700;
      margin-bottom: 24px;
      background: linear-gradient(to right, #fff, #e2e8f0);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .hero-text p {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 36px;
      max-width: 550px;
    }

    .btn-group {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--purple), #7c3aed);
      border: none;
      padding: 14px 36px;
      border-radius: 40px;
      font-weight: 600;
      color: white;
      font-size: 1rem;
      cursor: pointer;
      box-shadow: var(--shadow-purple);
      transition: var(--transition);
      text-decoration: none;
      display: inline-block;
    }

    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(168, 85, 247, 0.8);
      transform: translateY(-3px);
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--purple);
      padding: 14px 36px;
      border-radius: 40px;
      font-weight: 600;
      color: var(--white);
      transition: var(--transition);
      text-decoration: none;
      display: inline-block;
    }

    .btn-outline:hover {
      background: var(--purple);
      border-color: var(--purple);
      color: white;
    }

    .hero-image {
      flex: 1 1 400px;
      display: flex;
      justify-content: center;
    }

    .hero-image img {
      max-width: 100%;
      height: auto;
      border-radius: var(--radius-lg);
      box-shadow: 0 25px 50px -12px rgba(168, 85, 247, 0.4);
      border: 1px solid var(--glass-border);
    }

    /* 通用板块 */
    section {
      padding: 120px 0;
    }

    .section-title {
      font-size: 40px;
      font-weight: 700;
      margin-bottom: 20px;
      text-align: center;
      color: var(--white);
    }

    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 60px;
      font-size: 1.1rem;
    }

    /* 核心优势 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .feature-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-md);
      padding: 32px;
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
      align-items: flex-start;
    }

    .feature-card:hover {
      border-color: var(--purple);
      transform: translateY(-8px);
      box-shadow: 0 20px 30px -15px rgba(168, 85, 247, 0.5);
    }

    .feature-icon {
      font-size: 2.5rem;
      color: var(--cyan);
      margin-bottom: 24px;
    }

    .feature-card h3 {
      font-size: 1.5rem;
      margin-bottom: 14px;
    }

    /* 数据区块 */
    .stats {
      background: #0f172a;
      text-align: center;
    }

    .stat-grid {
      display: flex;
      justify-content: center;
      gap: 80px;
      flex-wrap: wrap;
    }

    .stat-item h3 {
      font-size: 3rem;
      font-weight: 700;
      color: var(--cyan);
    }

    /* 证言 */
    .testimonials {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }

    .testimonial-card {
      background: rgba(15, 23, 42, 0.7);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(168, 85, 247, 0.2);
      border-radius: var(--radius-md);
      padding: 32px;
    }

    /* FAQ */
    .faq-item {
      background: rgba(30, 41, 59, 0.5);
      backdrop-filter: blur(8px);
      border-left: 4px solid var(--purple);
      margin-bottom: 16px;
      border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
      padding: 20px 24px;
      cursor: pointer;
      transition: var(--transition);
    }

    .faq-item h3 {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 16px;
    }

    /* 页脚 */
    .footer {
      background: #0f172a;
      border-top: 1px solid var(--purple);
      padding: 60px 0 30px;
    }

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

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

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: flex; }
      .hero-text h1 { font-size: 38px; }
      .features-grid, .testimonials { grid-template-columns: 1fr; }
      .stat-grid { gap: 40px; }
      section { padding: 80px 0; }
      .container { padding: 0 20px; }
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10, 14, 23, 0.95);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      transform: translateX(-100%);
      transition: 0.4s;
      z-index: 999;
    }

    .mobile-menu.open {
      transform: translateX(0);
    }