  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/6.0.0-beta3/css/all.min.css">
  <style>
    /* 重置 + 基础字体（系统字体栈） */
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      /* margin: 0; */
      /* padding: 0; */
      /* font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif; */
      /* background: #f2f5f9; */
      /* display: flex; */
      /* flex-direction: column; */
      /* min-height: 100vh; */
    }

    /* 占位演示内容（可删除） */
    .demo-placeholder {
      flex: 1;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #8a9bb0;
      font-size: 15px;
      letter-spacing: 1px;
      padding: 40px 20px;
      background: #f2f5f9;
    }

    /* ===== 网站底部 · 大气风格 ===== */
    .site-footer {
      background: linear-gradient(145deg, #0b1420 0%, #101e2e 100%);
      color: #b8c7da;
      width: 100%;
      margin-top: auto;
      border-top: 1px solid rgba(255, 255, 255, 0.06);
      box-shadow: 0 -20px 40px -20px rgba(0, 0, 0, 0.3);
      position: relative;
      overflow: hidden;
    }

    /* 装饰光晕 */
    .site-footer::before {
      content: '';
      position: absolute;
      top: -120px;
      right: -80px;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(64, 128, 200, 0.08) 0%, transparent 70%);
      border-radius: 50%;
      pointer-events: none;
    }

    .site-footer::after {
      content: '';
      position: absolute;
      bottom: -150px;
      left: -100px;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle, rgba(40, 90, 150, 0.06) 0%, transparent 70%);
      border-radius: 50%;
      pointer-events: none;
    }

    .footer-container {
      max-width: 1220px;
      margin: 0 auto;
      padding: 44px 0px 0;
      position: relative;
      z-index: 1;
    }

    /* 四列网格 — 改为三列（去掉订阅后品牌加宽） */
    .footer-grid {
      display: grid;
      grid-template-columns: 1.6fr 1fr 1fr 1.3fr;
      gap: 40px;
      padding-bottom: 56px;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }

    .footer-col {
      display: flex;
      flex-direction: column;
    }

    /* 品牌区域 */
    .footer-brand {
      display: flex;
      flex-direction: column;
      gap: 18px;
    }

    .brand-logo {
      display: flex;
      align-items: center;
      gap: 12px;
      text-decoration: none;
    }

    .brand-logo .logo-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 44px;
      height: 44px;
      background: linear-gradient(135deg, #2d6bb4, #1e4a7a);
      border-radius: 12px;
      color: #ffffff;
      font-size: 20px;
      font-weight: 700;
      letter-spacing: -1px;
      box-shadow: 0 8px 16px -8px rgba(30, 80, 150, 0.5);
      flex-shrink: 0;
    }

    .brand-logo .logo-text {
      font-size: 26px;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: #f0f5fc;
      line-height: 1.2;
    }

    .brand-logo .logo-text span {
      color: #4a9eff;
    }

    .footer-brand p {
      font-size: 14px;
      line-height: 1.7;
      color: #9aafc8;
      max-width: 300px;
      margin-top: 4px;
    }

    /* 社交图标 */
    .social-links {
      display: flex;
      gap: 12px;
      margin-top: 10px;
      flex-wrap: wrap;
    }

    .social-links a {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 38px;
      height: 38px;
      border-radius: 50%;
      background: rgba(255, 255, 255, 0.05);
      border: 1px solid rgba(255, 255, 255, 0.08);
      color: #b0c2d8;
      font-size: 16px;
      text-decoration: none;
      transition: all 0.25s ease;
    }

    .social-links a:hover {
      background: rgba(74, 158, 255, 0.2);
      border-color: #4a9eff;
      color: #ffffff;
      transform: translateY(-3px);
    }

    /* 列标题 */
    .footer-title {
      font-size: 15px;
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 0.08em;
      color: #e2edfa;
      margin-bottom: 24px;
      position: relative;
      display: inline-block;
      padding-bottom: 12px;
    }

    .footer-title::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: 0;
      width: 28px;
      height: 2px;
      background: #4a9eff;
      border-radius: 2px;
    }

    /* 链接列表 */
    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .footer-links li a {
      font-size: 14px;
      color: #9aafc8;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: all 0.2s ease;
      line-height: 1.5;
    }

    .footer-links li a i {
      font-size: 10px;
      color: #4a9eff;
      /* opacity: 0; */
      transition: all 0.2s ease;
      width: 12px;
    }

    .footer-links li a:hover {
      color: #ffffff;
      transform: translateX(4px);
    }

    .footer-links li a:hover i {
      opacity: 1;
    }

    /* 联系信息列 */
    .footer-contact {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 18px;
    }

    .footer-contact li {
      display: flex;
      align-items: flex-start;
      gap: 14px;
      font-size: 14px;
      color: #9aafc8;
      line-height: 1.6;
    }

    .footer-contact li i {
      color: #4a9eff;
      font-size: 16px;
      margin-top: 3px;
      width: 18px;
      flex-shrink: 0;
      text-align: center;
    }

    .footer-contact li a {
      color: #9aafc8;
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer-contact li a:hover {
      color: #ffffff;
    }

    /* 版权栏 */
    .footer-bottom {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      justify-content: space-between;
      gap: 20px;
      padding: 28px 0;
      border-top: 1px solid rgba(255, 255, 255, 0.06);
      position: relative;
      z-index: 1;
    }

    .footer-bottom .copyright {
      font-size: 13px;
      color: #8398b2;
      letter-spacing: 0.02em;
    }

    .footer-bottom .copyright i {
      color: #4a9eff;
      margin: 0 4px;
      font-size: 12px;
    }

    .footer-bottom .legal-links {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 24px;
      list-style: none;
    }

    .footer-bottom .legal-links li a {
      font-size: 13px;
      color: #8398b2;
      text-decoration: none;
      transition: color 0.2s;
    }

    .footer-bottom .legal-links li a:hover {
      color: #ffffff;
    }

    /* ===== 响应式：手机端自适应 ===== */
    @media (max-width: 1024px) {
      .footer-grid {
        grid-template-columns: 1.4fr 1fr 1fr;
        gap: 36px 28px;
      }

      /* 品牌列跨两列，视觉更平衡 */
      .footer-brand {
        grid-column: 1 / 3;
      }

      /* 第四个列（联系）放到下一行并跨列，或保持单列 */
      .footer-col:last-child {
        grid-column: 1 / -1;  /* 跨所有列，避免尴尬空位 */
        display: grid;
        grid-template-columns: 1fr 1.5fr;
        gap: 30px;
        align-items: start;
        border-top: 1px solid rgba(255, 255, 255, 0.06);
        padding-top: 32px;
      }

      .footer-col:last-child .footer-title {
        margin-bottom: 16px;
      }

      .footer-contact {
        display: grid;
        grid-template-columns: 1fr 1fr;
        gap: 16px 24px;
      }
    }

    @media (max-width: 768px) {
      .footer-container {
        padding: 48px 24px 0;
      }

      .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px 24px;
        padding-bottom: 40px;
      }

      /* 品牌全宽 */
      .footer-brand {
        grid-column: 1 / -1;
      }

      .footer-brand p {
        max-width: 100%;
      }

      /* 两个链接列并排 */
      .footer-col:nth-child(2),
      .footer-col:nth-child(3) {
        grid-column: span 1;
      }

      /* 联系列全宽，内部两列 */
      .footer-col:last-child {
        grid-column: 1 / -1;
        grid-template-columns: 1fr;
        padding-top: 28px;
        border-top: 1px solid rgba(255, 255, 255, 0.06);
        margin-top: 4px;
      }

      .footer-contact {
        grid-template-columns: 1fr;
        gap: 14px;
      }

      .footer-bottom {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
        padding: 24px 0;
      }

      .footer-bottom .legal-links {
        gap: 18px;
        flex-wrap: wrap;
      }
    }

    @media (max-width: 520px) {
      .footer-container {
        padding: 36px 18px 0;
      }

      .footer-grid {
        grid-template-columns: 1fr;
        gap: 28px;
        padding-bottom: 32px;
      }

      .footer-brand {
        grid-column: 1;
      }

      .footer-col:nth-child(2),
      .footer-col:nth-child(3) {
        grid-column: 1;
      }

      /* 链接列之间加上细分割线，增强可读性 */
      .footer-col:nth-child(2) {
        border-bottom: 1px solid rgba(255, 255, 255, 0.06);
        padding-bottom: 24px;
      }

      .footer-col:nth-child(3) {
        border-bottom: 1px solid rgba(255, 255, 255, 0.06);
        padding-bottom: 24px;
      }

      .footer-col:last-child {
        grid-column: 1;
        padding-top: 20px;
        border-top: none;
      }

      .footer-title {
        font-size: 14px;
        margin-bottom: 18px;
      }

      .footer-links li a {
        font-size: 14px;
        padding: 4px 0;
      }

      .footer-contact li {
        font-size: 13px;
      }

      .footer-bottom {
        padding: 20px 0;
      }

      .footer-bottom .legal-links {
        gap: 14px;
      }

      .footer-bottom .legal-links li a {
        font-size: 12px;
      }

      .footer-bottom .copyright {
        font-size: 12px;
      }

      .brand-logo .logo-text {
        font-size: 22px;
      }

      .brand-logo .logo-icon {
        width: 38px;
        height: 38px;
        font-size: 18px;
      }

      .social-links a {
        width: 36px;
        height: 36px;
        font-size: 15px;
      }
    }

    /* 超小屏优化 */
    @media (max-width: 380px) {
      .footer-container {
        padding: 28px 14px 0;
      }

      .footer-bottom .legal-links {
        flex-direction: column;
        gap: 10px;
        align-items: flex-start;
      }

      .social-links {
        gap: 8px;
      }

      .social-links a {
        width: 34px;
        height: 34px;
        font-size: 14px;
      }
    }