How to change services icon's background color for each icon's background

Hi, firstly this theme is really awesome but I’ve some trobule with services icons, Like I sad in the title, I would like to change services icon’s background color but every icon’s background should be diffirent color. If I give a name for each span I can change color but that’s really boring, So is there any easy way to change the colors ?
Thank You ,
Regards.

Hello, please provide a link to your website and specify colors.

Kind Regards, Roman.