您可以使用JavaScript和CSS来实现此功能。以下是一些示例代码:

HTML:

<div class="scroll-hide">
  <!-- 这里是您的页面内容 -->
</div>

CSS:

.scroll-hide {
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  transition: all 0.3s ease-in-out;
}

.scroll-hide.hide {
  transform: translateY(100%);
}

JavaScript:

var prevScrollpos = window.pageYOffset;
window.onscroll = function() {
  var currentScrollPos = window.pageYOffset;
  if (prevScrollpos > currentScrollPos) {
    document.querySelector(".scroll-hide").classList.remove("hide");
  } else {
    document.querySelector(".scroll-hide").classList.add("hide");
  }
  prevScrollpos = currentScrollPos;
}

这段代码会监听窗口滚动事件，并在向上滚动时移除“hide”类，在向下滚动时添加“hide”类，从而实现了向下滚动出现，向上滚动隐藏的效果。

This error usually occurs when the GitHub credentials stored in the macOS keychain are invalid or outdated. Here are some steps you can take to resolve the issue:

1. Open the Keychain Access app on your Mac.
2. In the search bar, type "github.com".
3. Locate any entries related to GitHub and delete them by right-clicking and selecting "Delete" or pressing the "Delete" key on your keyboard.
4. Close the Keychain Access app and open Terminal.
5. Type the following command and press Enter: git credential-osxkeychain erase
6. Restart your computer.
7. Open Terminal and try accessing GitHub again. You may be prompted to enter your GitHub username and password.

If these steps do not resolve the issue, you may need to update your Git version or check if there are any network or firewall restrictions that are blocking GitHub access.