/* ===== 全局重置与变量 ===== */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    :root {
      --primary: #0a84ff;
      --primary-dark: #0066cc;
      --primary-light: #3a9eff;
      --bg-dark: #0b0f19;
      --bg-card: #131a2b;
      --bg-section: #0d1322;
      --text-main: #eef2f6;
      --text-secondary: #b0c0d0;
      --text-muted: #7a8a9a;
      --border-subtle: #1f2a3a;
      --accent-green: #00c48c;
      --accent-orange: #ff9f0a;
      --shadow-large: 0 20px 35px rgba(0, 0, 0, 0.5);
      --radius-md: 16px;
      --radius-lg: 24px;
      --radius-xl: 32px;
      --font-mono: 'SF Mono', 'Cascadia Code', 'Consolas', monospace;
    }

    body {
      font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'Noto Sans', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg-dark);
      color: var(--text-main);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      padding: 0 16px 0 16px;
      display: flex;
      flex-direction: column;
      align-items: center;
    }

    /* 主容器模拟最大宽度，保证在大屏下居中 */
    .page-wrapper {
      max-width: 1200px;
      width: 100%;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 48px;
      padding-top: 20px;
      padding-bottom: 40px;
    }

    /* ===== 顶部导航 ===== */
    .nav-bar {
      display: flex;
      justify-content: space-between;
      align-items: center;
      background: rgba(19, 26, 43, 0.8);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border: 1px solid var(--border-subtle);
      border-radius: 48px;
      padding: 10px 24px;
      margin-top: 8px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.3);
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: -0.3px;
      color: white;
    }

    .logo-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      background: var(--primary);
      width: 38px;
      height: 38px;
      border-radius: 12px;
      font-size: 1.5rem;
      box-shadow: 0 0 15px var(--primary);
    }

    .nav-links {
      display: flex;
      gap: 28px;
      font-weight: 500;
      color: var(--text-secondary);
    }

    .nav-links span {
      cursor: default;
      transition: color 0.2s;
      font-size: 0.95rem;
    }

    .nav-links span:hover {
      color: white;
    }

    .nav-cta {
      background: var(--primary);
      border: none;
      padding: 10px 22px;
      border-radius: 32px;
      font-weight: 600;
      color: white;
      font-size: 0.9rem;
      letter-spacing: 0.3px;
      cursor: default;
      box-shadow: 0 4px 14px rgba(10,132,255,0.5);
      transition: background 0.2s;
    }

    .nav-cta:hover {
      background: var(--primary-light);
    }

    /* ===== 主图模块（Hero） ===== */
    .hero-section {
      display: flex;
      flex-direction: column;
      align-items: center;
      text-align: center;
      background: radial-gradient(circle at 30% 20%, #1c2a45, #0b0f19 80%);
      border-radius: var(--radius-xl);
      padding: 50px 24px 40px;
      border: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-large);
    }

    .hero-badge {
      background: rgba(10, 132, 255, 0.15);
      color: var(--primary-light);
      padding: 6px 18px;
      border-radius: 30px;
      font-size: 0.8rem;
      font-weight: 600;
      letter-spacing: 0.5px;
      margin-bottom: 20px;
      border: 1px solid rgba(10,132,255,0.3);
    }

    .hero-title {
      font-size: clamp(2.2rem, 7vw, 3.8rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 16px;
      background: linear-gradient(to right, #ffffff, #b0d4ff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-secondary);
      max-width: 600px;
      margin-bottom: 30px;
    }

    .hero-image-placeholder {
      width: 100%;
      max-width: 750px;
      height: auto;
      aspect-ratio: 16 / 9;
      background: linear-gradient(135deg, #1f2a44, #0f172a);
      border-radius: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 15px 0 20px;
      border: 1px solid #2a3850;
      box-shadow: 0 10px 25px rgba(0,0,0,0.6);
      color: #5b6e8c;
      font-weight: 500;
      font-size: 1.1rem;
      position: relative;
      overflow: hidden;
    }

    .hero-image-placeholder::before {
      content: "? 三角洲行动 · 辅助视觉界面";
      display: flex;
      align-items: center;
      justify-content: center;
      width: 100%;
      height: 100%;
      background: rgba(10, 25, 50, 0.7);
      backdrop-filter: blur(2px);
      font-size: 1.5rem;
      color: #bcd5ff;
    }

    /* ===== 下载按钮组 ===== */
    .download-group {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      justify-content: center;
      margin-top: 10px;
    }

    .btn-primary {
      background: var(--primary);
      border: none;
      padding: 14px 32px;
      border-radius: 40px;
      font-weight: 700;
      font-size: 1rem;
      color: white;
      display: flex;
      align-items: center;
      gap: 8px;
      cursor: pointer;
      box-shadow: 0 8px 22px rgba(10,132,255,0.4);
      transition: 0.2s;
      text-decoration: none;
      letter-spacing: 0.3px;
    }

    .btn-primary:hover {
      background: #1e8eff;
      box-shadow: 0 10px 25px rgba(10,132,255,0.6);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--border-subtle);
      padding: 14px 28px;
      border-radius: 40px;
      font-weight: 600;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 6px;
      cursor: pointer;
      text-decoration: none;
      backdrop-filter: blur(8px);
    }

    .btn-secondary:hover {
      border-color: var(--primary);
      color: white;
    }

    /* ===== 卡片模块（特色卡片） ===== */
    .section-title {
      font-size: 2rem;
      font-weight: 700;
      margin-bottom: 24px;
      text-align: center;
      color: white;
    }

    .cards-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
      gap: 24px;
      margin-top: 10px;
    }

    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: var(--radius-lg);
      padding: 28px 20px;
      transition: transform 0.2s, border-color 0.2s;
      box-shadow: 0 8px 18px rgba(0, 0, 0, 0.4);
    }

    .feature-card:hover {
      transform: translateY(-5px);
      border-color: var(--primary);
    }

    .card-icon {
      font-size: 2.3rem;
      margin-bottom: 18px;
    }

    .feature-card h3 {
      font-size: 1.3rem;
      margin-bottom: 12px;
      font-weight: 650;
    }

    .feature-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
    }

    /* ===== 功能介绍详细区块 ===== */
    .function-list {
      display: flex;
      flex-direction: column;
      gap: 24px;
      background: var(--bg-section);
      border-radius: var(--radius-lg);
      padding: 30px 28px;
      border: 1px solid var(--border-subtle);
    }

    .function-item {
      display: flex;
      align-items: flex-start;
      gap: 16px;
      border-bottom: 1px solid #1f2a3a;
      padding-bottom: 18px;
    }

    .function-item:last-child {
      border-bottom: none;
      padding-bottom: 0;
    }

    .func-icon {
      font-size: 1.8rem;
      min-width: 40px;
    }

    .func-text h4 {
      font-weight: 650;
      margin-bottom: 6px;
    }

    .func-text p {
      color: var(--text-muted);
      font-size: 0.9rem;
    }

    /* ===== 部署教程模块 ===== */
    .tutorial-steps {
      display: flex;
      flex-direction: column;
      gap: 20px;
      counter-reset: step;
    }

    .step {
      display: flex;
      gap: 18px;
      background: #101826;
      border-radius: 20px;
      padding: 18px 22px;
      border-left: 4px solid var(--primary);
      align-items: center;
    }

    .step-number {
      background: var(--primary);
      color: white;
      font-weight: 700;
      width: 38px;
      height: 38px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.1rem;
    }

    /* ===== 常见问题 (FAQ) ===== */
    .faq-item {
      background: var(--bg-card);
      border-radius: 18px;
      padding: 18px 22px;
      margin-bottom: 14px;
      border: 1px solid var(--border-subtle);
    }

    .faq-question {
      font-weight: 700;
      font-size: 1.05rem;
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 8px;
    }

    .faq-answer {
      color: var(--text-secondary);
      margin-left: 30px;
      font-size: 0.92rem;
    }

    /* ===== 底部参数模块 ===== */
    .footer-params {
      background: #0a0f1a;
      border-radius: 28px;
      padding: 30px 25px;
      display: flex;
      flex-wrap: wrap;
      justify-content: space-between;
      align-items: center;
      border: 1px solid #1e2b3c;
      margin-top: 10px;
    }

    .param-item {
      display: flex;
      flex-direction: column;
      gap: 6px;
    }

    .param-label {
      font-size: 0.75rem;
      text-transform: uppercase;
      letter-spacing: 0.8px;
      color: var(--text-muted);
    }

    .param-value {
      font-weight: 700;
      font-size: 1.3rem;
      color: white;
    }

    .copyright {
      color: var(--text-muted);
      font-size: 0.8rem;
      text-align: center;
      margin-top: 20px;
    }

    /* 图标链接可替换图片提示 */
    .replace-note {
      font-size: 0.7rem;
      color: #5f6b7c;
    }

    hr {
      border-color: var(--border-subtle);
      margin: 8px 0 20px;
    }

    /* 响应式调整 */
    @media (max-width: 640px) {
      .nav-bar {
        flex-wrap: wrap;
        gap: 12px;
        justify-content: center;
      }
      .nav-links {
        gap: 16px;
        flex-wrap: wrap;
        justify-content: center;
      }
      .footer-params {
        flex-direction: column;
        align-items: flex-start;
        gap: 20px;
      }
    }