I recently created a responsive HTML page using Bootstrap, then converted it to WordPress and made some custom CSS adjustments. In the original HTML version of the page, the navbar collapse button worked perfectly when the screen was resized. However, after editing the custom CSS, the collapse buttons no longer function as intended.
ISSUE: When I resize my screen, the navbar links appear as a clickable button (good), but clicking on it does not reveal the menu items (bad).
The website in question is:
How can this problem be resolved?