Styling date in list widget

https://star.dazelprintandweb.com/wp-content/uploads/2015/12/Untitled-1.jpg

I want to style the date in the events list widget to look like the above image. I’ve searched everywhere for a way to wrap the elements like this:
<span class=”list-month”>Aug</span><span class=”list-day”>28</span>
but I am having no luck!! I also don’t want the time to show, or the @ symbol. Here’s what I have so far: https://www.star.dazelprintandweb.com

Can anyone point me to the file that has these elements? Or maybe there are variables or something that I can call in the list-widget template.

https://www.ads-software.com/plugins/the-events-calendar/