/* roulang page: index */
/* ===== 设计变量与基础重置 ===== */
    :root {
      --primary-bg: #0B0A1A;
      --card-bg: #1A1830;
      --nav-bg: rgba(11, 10, 26, 0.92);
      --purple: #7B2FBE;
      --cyan: #00E5FF;
      --orange: #FF6B35;
      --border-cyan: rgba(0, 229, 255, 0.18);
      --text-primary: #F0F0FF;
      --text-secondary: #B0B0C8;
      --text-muted: #6A6A82;
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-full: 40px;
      --shadow-glow: 0 0 28px rgba(123, 47, 190, 0.45);
      --shadow-cyan: 0 0 20px rgba(0, 229, 255, 0.5);
      --container-max: 1280px;
      --section-gap: 100px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      background-color: var(--primary-bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
      background-image: radial-gradient(circle at 40% 20%, rgba(123,47,190,0.08) 0%, transparent 40%);
      background-attachment: fixed;
    }
    
    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 28px;
    }
    
    img {
      max-width: 100%;
      height: auto;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s ease, opacity 0.2s;
    }
    
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }
    
    h1, h2, h3, h4 {
      font-weight: 700;
      letter-spacing: 0.02em;
      line-height: 1.3;
    }
    
    h1 {
      font-size: clamp(36px, 6vw, 56px);
    }
    h2 {
      font-size: 36px;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 24px;
    }
    
    .english-sub {
      font-family: 'Inter', sans-serif;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.1em;
      text-transform: uppercase;
      color: var(--cyan);
      margin-bottom: 10px;
      display: block;
    }
    
    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: transparent;
      backdrop-filter: blur(0px);
      transition: background 0.35s ease, backdrop-filter 0.35s ease, box-shadow 0.3s;
      padding: 16px 0;
    }
    .navbar.scrolled {
      background: var(--nav-bg);
      backdrop-filter: blur(16px);
      box-shadow: 0 8px 32px rgba(0,0,0,0.4);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 12px;
      font-weight: 700;
      font-size: 26px;
      color: white;
      letter-spacing: 1px;
    }
    .logo i {
      font-size: 32px;
      color: var(--cyan);
      text-shadow: 0 0 14px var(--cyan);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 38px;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 16px;
      position: relative;
      padding: 6px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--cyan);
      transition: width 0.3s;
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--cyan);
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .nav-cta {
      background: linear-gradient(135deg, var(--purple), var(--cyan));
      color: white;
      border-radius: 40px;
      padding: 12px 28px;
      font-weight: 600;
      font-size: 15px;
      box-shadow: 0 4px 18px rgba(123,47,190,0.45);
      border: none;
    }
    .nav-cta:hover {
      box-shadow: 0 0 24px rgba(0,229,255,0.6);
      transform: translateY(-1px);
    }
    
    /* 移动端底部导航 */
    .mobile-nav {
      display: none;
    }
    
    /* 模块标题结构 */
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    .section-title h2 {
      margin-bottom: 8px;
    }
    
    /* 首屏 */
    .hero {
      position: relative;
      min-height: 100vh;
      display: flex;
      align-items: center;
      overflow: hidden;
      background: var(--primary-bg);
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      isolation: isolate;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: radial-gradient(circle at 30% 50%, rgba(123,47,190,0.18) 0%, transparent 55%);
      z-index: 0;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 40px;
    }
    .hero-text {
      max-width: 650px;
    }
    .hero h1 {
      line-height: 1.25;
      text-shadow: 0 10px 28px rgba(0,0,0,0.7);
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 20px;
      color: var(--text-secondary);
      margin-bottom: 36px;
    }
    .hero-stat-decor {
      display: none;
    }
    .float-cta {
      position: fixed;
      bottom: 32px;
      right: 32px;
      z-index: 111;
      width: 68px;
      height: 68px;
      background: var(--orange);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 0 28px rgba(255,107,53,0.65);
      transition: 0.3s;
      color: white;
      font-size: 30px;
    }
    .float-cta:hover {
      transform: scale(1.08);
      background: #ff7f4d;
    }
    
    /* 数据看板 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }
    .stat-card {
      background: var(--card-bg);
      padding: 32px 20px;
      border-radius: var(--radius-md);
      text-align: center;
      border-top: 2px solid rgba(123,47,190,0.9);
      transition: 0.3s;
    }
    .stat-icon {
      font-size: 28px;
      color: var(--cyan);
      margin-bottom: 18px;
    }
    .stat-number {
      font-family: 'Inter', sans-serif;
      font-size: 46px;
      font-weight: 700;
      color: white;
      margin-bottom: 10px;
    }
    .stat-label {
      color: var(--text-muted);
      font-size: 15px;
    }
    
    /* 服务卡片网格 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      border: 1px solid var(--border-cyan);
      overflow: hidden;
      transition: 0.35s;
      position: relative;
    }
    .service-card:hover {
      box-shadow: 0 0 28px rgba(123,47,190,0.4);
      transform: translateY(-6px);
    }
    .card-img {
      height: 170px;
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .card-img::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, transparent 0%, rgba(11,10,26,0.8) 100%);
    }
    .card-badge {
      position: absolute;
      top: 14px;
      left: 14px;
      background: var(--orange);
      color: white;
      padding: 4px 14px;
      border-radius: 30px;
      font-size: 13px;
      font-weight: 600;
      z-index: 2;
    }
    .card-body {
      padding: 22px 24px;
    }
    .card-body h3 {
      margin-bottom: 12px;
    }
    .text-link {
      color: var(--orange);
      font-weight: 600;
      margin-top: 16px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    
    /* 对比区块 */
    .compare-wrapper {
      display: grid;
      grid-template-columns: 1fr 80px 1fr;
      align-items: center;
      gap: 20px;
    }
    .compare-column {
      background: rgba(26,24,48,0.7);
      border-radius: var(--radius-md);
      padding: 28px;
      border: 1px solid #2a2844;
    }
    .compare-column.highlight {
      border-color: var(--cyan);
      background: rgba(0,229,255,0.03);
    }
    .compare-item {
      display: flex;
      justify-items: space-between;
      margin-bottom: 18px;
    }
    .progress-bar {
      height: 6px;
      background: #2D2A44;
      border-radius: 10px;
      width: 100%;
      margin-top: 4px;
    }
    .progress-fill {
      height: 6px;
      border-radius: 10px;
      background: var(--orange);
    }
    .vs-badge {
      font-size: 28px;
      font-weight: 800;
      color: var(--cyan);
      text-shadow: 0 0 20px var(--cyan);
    }
    
    .btn-primary {
      background: linear-gradient(135deg, #7B2FBE, #00E5FF);
      color: white;
      border-radius: 40px;
      padding: 16px 40px;
      font-weight: 700;
    }
    
    /* FAQ */
    .faq-item {
      background: var(--card-bg);
      border-radius: var(--radius-sm);
      margin-bottom: 16px;
      border-left: 3px solid transparent;
      transition: 0.2s;
    }
    .faq-item.active {
      border-left-color: var(--cyan);
    }
    
    /* 表单 */
    .contact-form input, .contact-form select {
      background: #0B0A1A;
      border: 1px solid rgba(255,255,255,0.15);
      border-radius: 40px;
      padding: 14px 20px;
      color: white;
      width: 100%;
      margin: 12px 0;
    }
    
    footer {
      background: #070615;
      padding: 56px 0 24px;
    }
    
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .compare-wrapper { grid-template-columns: 1fr; }
      .vs-badge { margin: 16px 0; }
    }
    @media (max-width: 768px) {
      .desktop-nav { display: none; }
      .mobile-nav {
        display: flex;
        position: fixed;
        bottom: 0;
        left: 0;
        width: 100%;
        background: rgba(11,10,26,0.96);
        backdrop-filter: blur(20px);
        justify-content: space-around;
        padding: 12px 0;
        z-index: 99;
        border-top: 1px solid rgba(123,47,190,0.4);
      }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .float-cta { bottom: 90px; }
    }