Need help for interaction and animation

We are creating mobile version of our website. And trying to add animation to navigation drop-down menu.

We have already added hide/show to hamburger menu. We need slide functionality to show inner menu items on click event.

We tried to implement it but it is hampering the hamburger menu show/hide functionality.

Also need to understand, why I am seeing “Timed animation” of all applied element while adding interaction to other element?

Can you please assist us in implementing desired functionality?

Here is my site Read-Only: LINK
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