Some themes ask you not to edit the style.css file, instead use custom.css file. If you write code on custom.css, it will overwrite the same element style in style.css. I think this is done in order to prevent the loss of user styles on theme update, is it so?
How this works? Do they already include custom.css file in their theme? But how this file is included in the theme so that he theme look for style in custom.css first? Thanks.