Modify column number

Hello everyone,

At the moment, I have 4 columns, can anyone please help with the code to make the columns in my portfolio 5?

https://www.ptphotography.com

Thank you in adcance!

Add to Home > Design > Custom CSS

@media screen and (min-width:768px) {
div#gridThumbs {
    grid-template-columns: repeat(5,minmax(0,1fr)) !important;
}
}