Image in navigation bar

Hi everyone,

Context: I have created a navigation bar which has a drop down for products with images 

Problem: Only the text in the drop down has a hover effect and can be clicked on to get to the page but not the image.

Query: How do I add a hover effect to the image in my drop down which can be clicked on to get to the page, similar to the text?

https://blue-goose-kfxs.squarespace.com/config/design/custom-css 

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