网站功能增加调整代码

1、网站返回网页顶部代码

<!-- Back To Top Button -->
<button id="backToTop" aria-label="Back to top">
  ↑
</button>

<style>
  #backToTop {
    position: fixed;
    right: 28px;
    bottom: 90px;
    width: 46px;
    height: 46px;
    border: 2px solid #ff4b2b;
    background: #164782;
    color: #ffffff;
    font-size: 26px;
    font-weight: bold;
    line-height: 1;
    border-radius: 4px;
    cursor: pointer;
    z-index: 9999;
    display: none;
    align-items: center;
    justify-content: center;
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.18);
    transition: all 0.3s ease;
  }

  #backToTop:hover {
    background: #ff4b2b;
    color: #ffffff;
    transform: translateY(-3px);
  }

  #backToTop.show {
    display: flex;
  }

  @media (max-width: 768px) {
    #backToTop {
      right: 18px;
      bottom: 70px;
      width: 42px;
      height: 42px;
      font-size: 24px;
    }
  }
</style>

<script>
  document.addEventListener("DOMContentLoaded", function () {
    const backToTop = document.getElementById("backToTop");

    window.addEventListener("scroll", function () {
      if (window.scrollY > 300) {
        backToTop.classList.add("show");
      } else {
        backToTop.classList.remove("show");
      }
    });

    backToTop.addEventListener("click", function () {
      window.scrollTo({
        top: 0,
        behavior: "smooth"
      });
    });
  });
</script>