Remove gridlines in AG Grid and Streamlit app

I am making an application using Streamlit and AG Grid in a Python project.

I have below table which I have been able to format as I wanted, BUT i can’t seem to get rid of the ‘gridlines’ in the table. When I try to pass some custom css to the AG Grid table, the borders that I’m editing are the ones ‘inside’ the cell, and not the ones that you can see here. e.g. I want the red row to just be redd all the way across without the lines in between each cell.

Can someone help me on how to do that?

Example of the table where I need the gridlines to disappear