Does not work for some reason

I wanted to remove the ‘Storefront designed by Woocommerce’ footer credit by using below code into the footer section of your plugin.

.site-info {
display: none;}

I tried inserting this code in each of the boxes under the footer section, but it didn’t work. I tried many other similar codes by inserting there but none worked.

Can you please advise how to get it to work.