如何使用jquery滚动功能在一个页面上工作但在Wordpress网站中没有其他页面

In a wordpress site, I removed the current-menu-item class to a long scrolling page, and added it back once the top section is above a certain height. This works well, but scrolling on any other page induces the addClass back on the first page navigation, as well as the current (visible) page. The site can be viewed at In a wordpress site, I removed the current-menu