twin vector
Hello Youssef,
it should be the same way you have done for the rest of the element you have switch to dark mode with prefers-color-scheme: dark or a specific class.
The thing which is not working in your code is the fact that you attribute a color in your javascript code :
hamburgerBtn.style.color = '#FCFFC1';
and this cannot be changed except in javacript again.
Otherwise, you should apply a new class when you do the switch to dark mode and define a color in your css.