The current dropdown menu is simple of course however, In my opinion, it can be made much more minimal, and much simpler CSS could be applied to beautify it.
1. The on-hover color change of the navbar items should be changed. Reasons can create a dizzy feeling on the continuous color change of text & also this method is rarely applied on any website.
An alternative approach to it - Just apply a border-bottom approach when hovering over navbar menu items. Also when hovered around the ones with a dropdown menu, rotate it by 135 deg with the transition. Many websites including Github, Myntra, etc use this technique.
2. For the ones with the dropdown menu on hover over navbar items, it has really less width and when you navigate through the dropdown items, you observe that there is a gray background color. Personally, I don't think it suits the design.
An alternative approach to it - Increase the width and while hovering over the dropdown menu items, just increase its font-weight to provide the effect.
This is the preview of how the design would be.