Tailwind css Transitions are not working with Javascript

Hello so i started working with tailwind , doing a small project of a pop up slider, but the tailwind transitions classes dont seem to work, the pop up is triggered and appears but theere is no animations even tho i already set them in my classes with tailwind css , You can check the code bellow.

[JS FILE]
HTML FILE]

i tried adding a transition durations to the pop up sliding but it didnt work