Navigation bar does not shift color

Hello, I have a Navigation bar problem!

When I click the problem button, it can move to the problem section. But, the button did not change the light brown color. However, when I scroll up a little bit, the button shifts the color. Does anyone know how to fix it? Thanks

I don’t know why the read-only cannot show the color :frowning:

Here is my site Read-Only:
[1]: Webflow - chiiiiihfanportfolio