CSS Hover Animations

Site URL: https://www.harmoneywealthaz.com/services

website: https://www.harmoneywealthaz.com/ourstory#anchor-harmoneydifference

https://www.harmoneywealthaz.com/services

I am hoping to add an element or some sort of css animation upon hover on the dropdown/accordion menu to show the user that the accordion is clickable. 

Has this been done before on squarespace? My mouse doesn't changer upon hover so the text doesn't appear to be clickable.

 @tuanphan 

Add to Page Settings > Advanced > Header

<style>
  .markdown-block h4 {
    border-bottom: 1px solid transparent;
}
.markdown-block h4:hover {
    border-bottom-color: black;
    display: inline-block;
}
</style>