Hi Rafael,
I see. This Block isn’t from GeneratePress or GenerateBlocks. It’s from WordPress. We have no control over that Block. Are you trying to alter how it looks in the front end?
If so, you can give the File Block a class of cu-download-button
in its class list. Example: https://share.getcloudapp.com/v1uEvWlv
Then, add this through Appearance > Customize > Additional CSS:
.wp-block-file.cu-download-button .wp-element-button{
padding: 5px 10px;
background-color: #7777ee;
color: #fff;
}
You may change the values to your preference.
If you’re referring to something else, let us know.