Add the THEME.SCSS code to the bottom of Theme.scss.liquid which is located under Assets folder:

Add the Product-grid-item.liquid code under Snippets folder. Delete everything in this file just paste the code below

There are tow files one has bigger front with dash and one is smaller.

All codes can be found here-
Serdumps/Shopify-Hover-on-Product-Brooklyn (github.com)

Video-
https://youtu.be/QrklDQJEXxk