/* roulang page: index */
:root {
      --primary: #FF4D1C;
      --primary-dark: #E04318;
      --secondary: #7B2FFF;
      --bg-deep: #0A0A0F;
      --card-bg: #14141F;
      --section-bg: #1A1A2E;
      --text-main: #FFFFFF;
      --text-body: #B0B0C0;
      --text-muted: #6B6B80;
      --success: #00E676;
      --warning: #FFAB00;
      --info: #448AFF;
      --border-light: rgba(123, 47, 255, 0.15);
      --border-glow: rgba(255, 77, 28, 0.5);
      --shadow-card: 0 4px 24px rgba(0,0,0,0.4);
      --shadow-hover: 0 8px 40px rgba(255,77,28,0.15);
      --radius-md: 12px;
      --radius-sm: 8px;
      --container: 1280px;
      --transition: 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      background-color: var(--bg-deep);
      color: var(--text-body);
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4, .stat-number, .din-font {
      font-family: 'DIN Alternate', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      font-weight: 700;
      color: var(--text-main);
    }
    h1 { font-size: 48px; line-height: 56px; }
    h2 { font-size: 36px; line-height: 44px; margin-bottom: 20px; }
    h3 { font-size: 22px; line-height: 30px; color: var(--text-main); margin-bottom: 10px; }
    p { color: var(--text-body); margin-bottom: 16px; }
    a { text-decoration: none; color: inherit; }
    img { max-width: 100%; height: auto; display: block; }
    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 40px;
    }
    section {
      padding: 100px 0;
    }
    @media (max-width: 1024px) {
      h1 { font-size: 38px; line-height: 46px; }
      h2 { font-size: 30px; line-height: 38px; }
      .container { padding: 0 24px; }
      section { padding: 70px 0; }
    }
    @media (max-width: 768px) {
      h1 { font-size: 32px; line-height: 40px; }
      h2 { font-size: 26px; line-height: 34px; }
      h3 { font-size: 20px; line-height: 28px; }
      body { font-size: 15px; }
      .container { padding: 0 20px; }
      section { padding: 60px 0; }
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      background: transparent;
      transition: background var(--transition), backdrop-filter var(--transition);
      padding: 0 20px;
    }
    .navbar.scrolled {
      background: rgba(10,10,15,0.94);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--container);
      margin: 0 auto;
    }
    .logo {
      font-size: 24px;
      font-weight: 800;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: 1px;
    }
    .logo-icon {
      display: inline-block;
      width: 24px;
      height: 24px;
      background: var(--primary);
      border-radius: 4px;
      position: relative;
      transform: rotate(45deg);
      margin-right: 6px;
    }
    .logo-icon::after {
      content: '';
      position: absolute;
      top: 2px;
      left: 2px;
      width: 10px;
      height: 10px;
      background: var(--bg-deep);
      border-radius: 2px;
    }
    .logo-text { color: #FF4D1C; }
    .nav-menu {
      display: flex;
      gap: 32px;
      list-style: none;
    }
    .nav-menu a {
      color: var(--text-body);
      font-weight: 500;
      transition: color var(--transition);
      position: relative;
      padding-bottom: 4px;
      font-size: 15px;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--primary);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      cursor: pointer;
      gap: 5px;
      z-index: 1001;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--text-main);
      transition: var(--transition);
    }
    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--bg-deep);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 36px;
        transform: translateY(-100%);
        transition: transform 0.4s ease;
        z-index: 1001;
      }
      .nav-menu.active {
        transform: translateY(0);
      }
      .nav-menu a {
        font-size: 22px;
      }
      .hamburger {
        display: flex;
      }
    }
    /* 按钮 */
    .btn {
      display: inline-block;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: all 0.25s ease;
      border: none;
      cursor: pointer;
      font-size: 16px;
      text-align: center;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 0 20px rgba(255,77,28,0.4);
    }
    .btn-secondary {
      border: 1.5px solid var(--secondary);
      color: var(--secondary);
      background: transparent;
    }
    .btn-secondary:hover {
      background: rgba(123,47,255,0.1);
      border-color: var(--primary);
      color: var(--primary);
    }
    /* Hero */
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-left .stats-row {
      display: flex;
      gap: 30px;
      margin-top: 40px;
    }
    .stat-item {
      background: rgba(20,20,31,0.8);
      padding: 16px 20px;
      border-radius: var(--radius-sm);
      text-align: center;
      border: 1px solid var(--border-light);
    }
    .stat-number {
      font-size: 28px;
      color: var(--primary);
      display: block;
    }
    .hero-right {
      background: radial-gradient(circle at center, rgba(123,47,255,0.12) 0%, #0A0A0F 80%);
      padding: 30px;
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      position: relative;
      min-height: 320px;
    }
    .dashboard-mock {
      width: 100%;
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      justify-content: center;
    }
    .db-circle {
      width: 80px;
      height: 80px;
      border-radius: 50%;
      border: 4px solid var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--primary);
      background: rgba(255,77,28,0.05);
    }
    @media (max-width: 768px) {
      .hero-grid { grid-template-columns: 1fr; gap: 30px; }
      .hero-right { min-height: 200px; }
      .stats-row { flex-wrap: wrap; }
    }
    /* 卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .card {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 32px;
      transition: all var(--transition);
    }
    .card:hover {
      border-color: var(--border-glow);
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .card-icon {
      width: 48px;
      height: 48px;
      background: rgba(255,77,28,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 24px;
    }
    /* 服务矩阵 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .service-item {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius-md);
      border: 1px solid rgba(123,47,255,0.1);
      display: flex;
      flex-direction: column;
    }
    @media (max-width: 1024px) {
      .cards-grid, .service-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .cards-grid, .service-grid { grid-template-columns: 1fr; }
    }
    /* 数据对比 */
    .compare-row {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
      margin-top: 30px;
    }
    .compare-block {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius-md);
      text-align: center;
      border-left: 4px solid var(--secondary);
    }
    .compare-value {
      font-size: 36px;
      margin: 10px 0;
    }
    @media (max-width: 768px) {
      .compare-row { grid-template-columns: 1fr; }
    }
    /* 步骤条 */
    .steps {
      display: flex;
      justify-content: space-between;
      margin-top: 50px;
      position: relative;
    }
    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }
    .step-circle {
      width: 50px;
      height: 50px;
      border-radius: 50%;
      background: var(--bg-deep);
      border: 2px solid var(--secondary);
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 15px;
      font-weight: 700;
      color: white;
    }
    .step.active .step-circle {
      background: var(--primary);
      border-color: var(--primary);
    }
    .step::after {
      content: '';
      position: absolute;
      top: 25px;
      right: -50%;
      width: 100%;
      height: 2px;
      background: #1A1A2E;
      z-index: -1;
    }
    .step:last-child::after { display: none; }
    @media (max-width: 768px) {
      .steps { flex-direction: column; gap: 30px; }
      .step::after { display: none; }
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.06);
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 600;
      color: white;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-body);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 15px;
    }
    /* 表单 */
    .form-group input, .form-group textarea {
      width: 100%;
      padding: 14px 18px;
      background: #14141F;
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: var(--radius-sm);
      color: white;
      font-family: inherit;
      margin-bottom: 16px;
      transition: border var(--transition);
    }
    .form-group input:focus, .form-group textarea:focus {
      border-color: var(--primary);
      outline: none;
      box-shadow: 0 0 0 3px rgba(255,77,28,0.15);
    }
    footer a { color: var(--text-body); }
    footer a:hover { color: var(--primary); }