/* roulang page: index */
:root {
      --deep-blue: #0A0E27;
      --deep-blue2: #0F1429;
      --electric-purple: #7C3AED;
      --electric-purple-light: #A78BFA;
      --cyan-glow: #00F0FF;
      --white: #FFFFFF;
      --gray-light: #F0F2F5;
      --gray-dark: #1E2336;
      --text-strong: rgba(255,255,255,0.95);
      --text-body: rgba(255,255,255,0.85);
      --text-soft: rgba(255,255,255,0.6);
      --glass-bg: rgba(255,255,255,0.04);
      --glass-border: rgba(255,255,255,0.08);
      --card-radius: 20px;
      --btn-radius: 50px;
      --shadow-purple: 0 0 20px rgba(124,58,237,0.5);
      --shadow-purple-hover: 0 0 35px rgba(124,58,237,0.8);
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
      --container-max: 1280px;
      --section-gap: 130px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--deep-blue);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(10, 14, 39, 0.75);
      backdrop-filter: blur(25px);
      border-bottom: 1px solid rgba(124,58,237,0.25);
      padding: 15px 0;
    }
    .nav-container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--white);
      letter-spacing: 1px;
    }
    .logo i {
      color: var(--electric-purple-light);
      font-size: 1.8rem;
      filter: drop-shadow(0 0 8px var(--electric-purple));
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 5px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--electric-purple-light);
      transition: width 0.3s;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-nav {
      background: var(--electric-purple);
      color: white;
      padding: 10px 24px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      box-shadow: var(--shadow-purple);
      transition: all 0.3s;
      margin-left: 10px;
    }
    .btn-nav:hover {
      background: var(--electric-purple-light);
      box-shadow: var(--shadow-purple-hover);
      transform: scale(1.02);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: white;
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(10,14,39,0.96);
        backdrop-filter: blur(20px);
        flex-direction: column;
        gap: 20px;
        padding: 30px;
        border-bottom: 1px solid var(--electric-purple);
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: block;
      }
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      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: radial-gradient(circle at 30% 40%, rgba(124,58,237,0.3), transparent 70%);
      pointer-events: none;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 50px;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 1 1 55%;
    }
    .hero-right {
      flex: 1 1 45%;
      display: flex;
      justify-content: center;
      animation: float 5s infinite alternate;
    }
    @keyframes float {
      0% { transform: translateY(0); }
      100% { transform: translateY(-12px); }
    }
    .hero-right img {
      max-height: 380px;
      border-radius: 32px;
      box-shadow: 0 25px 50px -12px rgba(124,58,237,0.6);
      border: 1px solid rgba(255,255,255,0.15);
    }
    h1 {
      font-size: clamp(2.5rem, 6vw, 3.8rem);
      font-weight: 800;
      color: white;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-soft);
      margin-bottom: 35px;
      max-width: 500px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--electric-purple), var(--electric-purple-light));
      color: white;
      padding: 14px 38px;
      border-radius: var(--btn-radius);
      font-weight: 700;
      box-shadow: var(--shadow-purple);
      transition: 0.3s;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-primary:hover {
      box-shadow: var(--shadow-purple-hover);
      transform: translateY(-3px);
    }
    .btn-outline {
      border: 1px solid rgba(255,255,255,0.3);
      color: white;
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      backdrop-filter: blur(10px);
      transition: 0.3s;
    }
    .btn-outline:hover {
      border-color: var(--electric-purple-light);
      background: rgba(124,58,237,0.1);
    }
    /* sections */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      font-size: 2.5rem;
      font-weight: 700;
      color: white;
      margin-bottom: 20px;
      text-align: center;
    }
    .highlight-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      margin-top: 50px;
    }
    .card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--card-radius);
      padding: 32px;
      transition: 0.3s;
    }
    .card:hover {
      border-color: var(--electric-purple-light);
      transform: translateY(-6px);
      box-shadow: 0 20px 30px rgba(124,58,237,0.2);
    }
    .card-icon {
      font-size: 2.2rem;
      color: var(--cyan-glow);
      margin-bottom: 20px;
    }
    .card h3 {
      color: white;
      font-size: 1.4rem;
      margin-bottom: 12px;
    }
    /* 瀑布流 */
    .waterfall {
      display: flex;
      flex-direction: column;
      gap: 60px;
      margin-top: 50px;
    }
    .waterfall-item {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .waterfall-item.reverse {
      flex-direction: row-reverse;
    }
    .waterfall-img {
      flex: 1;
      border-radius: 18px;
      overflow: hidden;
    }
    .waterfall-img img {
      border-radius: 18px;
      transition: 0.4s;
    }
    .waterfall-img:hover img {
      transform: scale(1.02);
    }
    .waterfall-text {
      flex: 1;
    }
    .tag {
      background: rgba(124,58,237,0.15);
      color: var(--electric-purple-light);
      padding: 4px 14px;
      border-radius: 30px;
      font-size: 0.8rem;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 12px;
    }
    /* 数据 */
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 30px;
      margin-top: 50px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--cyan-glow);
      text-shadow: 0 0 15px rgba(0,240,255,0.5);
    }
    /* 对比表 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 50px;
    }
    .plan-card {
      background: var(--glass-bg);
      backdrop-filter: blur(18px);
      border: 1px solid var(--glass-border);
      border-radius: 24px;
      padding: 32px;
      text-align: center;
    }
    .plan-card.recommend {
      border-color: var(--electric-purple);
      box-shadow: 0 0 25px rgba(124,58,237,0.4);
      transform: scale(1.02);
    }
    .plan-feature {
      margin: 15px 0;
    }
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
      margin-top: 40px;
    }
    .faq-item {
      background: rgba(255,255,255,0.02);
      border-radius: 16px;
      padding: 18px 24px;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      color: white;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.4s;
      color: var(--text-soft);
    }
    .faq-item.active .faq-answer {
      max-height: 120px;
      margin-top: 12px;
    }
    .cta-banner {
      background: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
      border-radius: 38px;
      padding: 70px 30px;
      text-align: center;
      margin: 50px auto;
    }
    footer {
      background: var(--deep-blue2);
      padding: 60px 0 30px;
      border-top: 1px solid rgba(255,255,255,0.05);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .hero-grid, .waterfall-item, .waterfall-item.reverse {
        flex-direction: column;
      }
      .highlight-grid, .pricing-grid, .faq-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
    }