/* roulang page: index */
:root {
      --primary: #E94057;
      --primary-hover: #D12E43;
      --secondary: #6C3CE1;
      --secondary-hover: #5A2FCC;
      --deep-bg: #0F1923;
      --deep-bg-light: #1A2A3A;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text-primary: #1E293B;
      --text-secondary: #64748B;
      --border: #E2E8F0;
      --border-light: #CBD5E1;
      --green: #10B981;
      --red: #EF4444;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 10px 25px rgba(0,0,0,0.1), 0 4px 10px rgba(0,0,0,0.05);
      --font-stack: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
    }

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

    body {
      font-family: var(--font-stack);
      background-color: var(--bg);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border);
      height: 64px;
      display: flex;
      align-items: center;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 20px;
      font-weight: 700;
      color: var(--text-primary);
      text-decoration: none;
      letter-spacing: -0.3px;
    }

    .logo-icon {
      width: 24px;
      height: 24px;
      background: var(--primary);
      transform: rotate(45deg);
      border-radius: 3px;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      margin-left: auto;
      list-style: none;
      align-items: center;
    }

    .nav-links a {
      font-size: 14px;
      font-weight: 500;
      color: #475569;
      text-decoration: none;
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--text-primary);
      cursor: pointer;
      margin-left: auto;
    }

    /* 区块间距 */
    section {
      padding: 80px 0;
    }

    @media (max-width: 640px) {
      section {
        padding: 48px 0;
      }
    }

    /* 按钮 */
    .btn-primary {
      background: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 16px;
      text-decoration: none;
      display: inline-block;
      transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(233,64,87,0.3);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      font-weight: 600;
      font-size: 16px;
      text-decoration: none;
      display: inline-block;
      transition: background 0.2s, color 0.2s;
    }

    .btn-outline:hover {
      background: rgba(233,64,87,0.08);
    }

    .btn-submit {
      background: var(--secondary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 16px;
      border: none;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
    }

    .btn-submit:hover {
      background: var(--secondary-hover);
      transform: scale(1.02);
    }

    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border);
      transition: transform 0.25s, box-shadow 0.25s;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }

    /* Hero 数据看板闪烁 */
    .data-glow {
      animation: pulse-glow 2s infinite;
    }

    @keyframes pulse-glow {
      0% { box-shadow: 0 0 20px rgba(108,60,225,0.3); }
      50% { box-shadow: 0 0 35px rgba(233,64,87,0.5); }
      100% { box-shadow: 0 0 20px rgba(108,60,225,0.3); }
    }

    .trend-up { color: var(--green); }
    .trend-down { color: var(--red); }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border);
    }

    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 0;
      font-size: 16px;
      font-weight: 600;
      text-align: left;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text-primary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.35s ease;
      font-size: 15px;
      color: var(--text-secondary);
      line-height: 1.7;
      padding: 0 0;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
    }

    .faq-item.active .faq-icon {
      transform: rotate(180deg);
      color: var(--primary);
    }

    .faq-icon {
      transition: transform 0.3s, color 0.3s;
    }

    .badge {
      background: rgba(108,60,225,0.1);
      color: var(--secondary);
      font-size: 13px;
      font-weight: 600;
      padding: 4px 10px;
      border-radius: 20px;
      display: inline-block;
    }

    /* 比较面板 */
    .compare-panel-left {
      background: #FFF5F5;
      border: 1px solid #FECACA;
    }

    .compare-panel-right {
      background: #F0FDF4;
      border: 1px solid #BBF7D0;
    }

    /* 输入框 */
    .form-input {
      background: white;
      border: 1px solid var(--border);
      border-radius: var(--radius-btn);
      padding: 14px 16px;
      font-size: 16px;
      width: 100%;
      transition: border 0.2s, box-shadow 0.2s;
    }

    .form-input:focus {
      outline: none;
      border-color: var(--secondary);
      box-shadow: 0 0 0 3px rgba(108,60,225,0.2);
    }

    /* 页脚 */
    .footer {
      background: var(--deep-bg);
      color: rgba(255,255,255,0.8);
      padding: 60px 0 30px;
    }

    .footer a {
      color: rgba(255,255,255,0.7);
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer a:hover {
      color: white;
    }

    .social-icon {
      width: 40px;
      height: 40px;
      border-radius: 50%;
      border: 1px solid rgba(255,255,255,0.3);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      margin-right: 12px;
      transition: background 0.2s, border-color 0.2s;
    }

    .social-icon:hover {
      background: var(--primary);
      border-color: var(--primary);
    }

    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }

    @media (max-width: 640px) {
      .container {
        padding: 0 16px;
      }
      h1 {
        font-size: 28px !important;
        line-height: 1.3 !important;
      }
      h2 {
        font-size: 24px !important;
      }
    }