/* roulang page: index */
:root {
      --primary-blue: #4E6EF2;
      --vital-green: #00B578;
      --bg-page: #F5F6FA;
      --card-white: #FFFFFF;
      --text-dark: #1F2329;
      --text-muted: #86909C;
      --glass-border: rgba(255,255,255,0.8);
      --glass-bg: rgba(255,255,255,0.65);
      --radius-card: 18px;
      --radius-button: 50px;
      --shadow-card: 0 10px 25px -8px rgba(0,0,0,0.05), 0 4px 10px rgba(0,0,0,0.02);
      --shadow-glow: 0 0 20px rgba(78,110,242,0.4);
      --transition-smooth: all 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-dark);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 80px;
      background: transparent;
      transition: background 0.3s ease, backdrop-filter 0.3s ease, box-shadow 0.3s ease;
      display: flex;
      align-items: center;
    }
    .navbar.scrolled {
      background: rgba(31, 35, 41, 0.8);
      backdrop-filter: blur(20px);
      box-shadow: 0 10px 20px -10px rgba(0,0,0,0.1);
      border-bottom: 1px solid rgba(255,255,255,0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: white;
      text-shadow: 0 4px 12px rgba(0,0,0,0.2);
      transition: color 0.3s;
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--vital-green);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.9);
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      transition: color 0.2s;
      position: relative;
    }
    .nav-links a:hover {
      color: white;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 1001;
      background: rgba(255,255,255,0.15);
      backdrop-filter: blur(8px);
      padding: 10px;
      border-radius: 12px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: white;
      transition: 0.3s;
      display: block;
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(0,0,0,0.75);
      backdrop-filter: blur(30px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      transform: translateY(-100%);
      transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
      z-index: 999;
    }
    .mobile-menu.active {
      transform: translateY(0);
    }
    .mobile-menu a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
      text-decoration: none;
    }
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #0b1a33 0%, #1a2f4a 100%);
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      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-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
      position: relative;
      z-index: 2;
    }
    .hero-left h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      background: linear-gradient(135deg, #FFFFFF 0%, #B0C4FF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 1.2rem;
    }
    .hero-left p {
      color: rgba(255,255,255,0.7);
      font-size: 1.2rem;
      margin-bottom: 2rem;
      max-width: 90%;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary-blue);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      box-shadow: var(--shadow-glow);
      transition: var(--transition-smooth);
      text-decoration: none;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      filter: brightness(1.1);
      transform: translateY(-2px);
      box-shadow: 0 0 30px rgba(78,110,242,0.6);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid rgba(255,255,255,0.5);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-button);
      font-weight: 500;
      cursor: pointer;
      transition: var(--transition-smooth);
      text-decoration: none;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
      border-color: white;
    }
    .hero-right {
      display: flex;
      justify-content: center;
    }
    .hero-visual {
      width: 100%;
      max-width: 450px;
      aspect-ratio: 1/1;
      background: radial-gradient(circle at 30% 30%, rgba(78,110,242,0.2), transparent);
      border-radius: 40px;
      backdrop-filter: blur(5px);
      border: 1px solid rgba(255,255,255,0.2);
    }
    /* section通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 2.4rem;
      font-weight: 600;
      margin-bottom: 1rem;
      color: var(--text-dark);
      text-align: center;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 50px;
      font-size: 1.1rem;
    }
    /* 解决方案卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: 30px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      color: var(--text-dark);
    }
    .glass-card:hover {
      transform: translateY(-8px);
      box-shadow: 0 20px 30px rgba(78,110,242,0.12);
      border-color: rgba(78,110,242,0.3);
    }
    .glass-card .icon {
      font-size: 2rem;
      color: var(--primary-blue);
      margin-bottom: 16px;
    }
    /* 数据深色区 */
    .dark-block {
      background: #121826;
      color: white;
      border-radius: 40px;
      margin: 0 24px;
      padding: 60px 40px;
    }
    .stats-flex {
      display: flex;
      justify-content: space-around;
      align-items: center;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--vital-green);
    }
    /* 左右图文 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin: 60px 0;
    }
    .feature-img {
      flex: 1;
      background: #e9edf4;
      border-radius: 28px;
      overflow: hidden;
      box-shadow: 0 30px 40px rgba(0,0,0,0.06);
    }
    .feature-img img {
      width: 100%;
      height: auto;
      display: block;
    }
    .feature-text {
      flex: 1;
    }
    /* 证言卡片 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .testimonial-card {
      background: white;
      border-radius: 24px;
      padding: 32px;
      box-shadow: var(--shadow-card);
      position: relative;
      overflow: hidden;
    }
    .testimonial-card::before {
      content: "";
      position: absolute;
      width: 120px;
      height: 120px;
      background: radial-gradient(circle, rgba(78,110,242,0.08) 0%, transparent 70%);
      top: -20px;
      right: -20px;
    }
    /* FAQ */
    .faq-item {
      background: white;
      border-radius: 16px;
      margin-bottom: 16px;
      padding: 20px 24px;
      cursor: pointer;
      transition: 0.2s;
      border: 1px solid #eee;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
      margin-top: 10px;
    }
    /* CTA */
    .cta-block {
      background: linear-gradient(135deg, #1e2f5a, #0f1a2f);
      border-radius: 48px;
      margin: 0 24px;
      text-align: center;
      padding: 80px 20px;
    }
    /* footer */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      color: #ccc;
    }
    @media (max-width: 1024px) {
      .card-grid { grid-template-columns: repeat(2,1fr); }
      .testimonial-grid { grid-template-columns: 1fr; }
      .feature-row { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-grid { grid-template-columns: 1fr; }
      .card-grid { grid-template-columns: 1fr; }
      .dark-block { margin: 0; }
    }