Hi @CuriousChip great question and thank you so much for posting this!
What is happening is you have a class on the text element within the dropdown so that is overriding the styles from the dropdown element itself.
To achieve this effect, you will need to remove the classes from the text element, and then create the styles instead on the
dropdown toggle element instead.
Here is a GIF showing the steps to achieve that hover style: https://cl.ly/rBni
Please let me know if this is helpful or if you have any additional questions feel free to tag me @Waldo in your posts, I’m here to help ♂️